Merge pull request #1551 from peterdmv/peterdmv/stdlib/add_uri_string/OTP-14496

Implement new uri_string module in stdlib

12 files changed, 3334 insertions, 0 deletions

diff --git a/lib/stdlib/doc/src/Makefile b/lib/stdlib/doc/src/Makefile
index 93eac8220d..aeed79408b 100644
--- a/lib/stdlib/doc/src/Makefile
+++ b/lib/stdlib/doc/src/Makefile
@@ -98,6 +98,7 @@ XML_REF3_FILES = \
 	sys.xml \
 	timer.xml \
 	unicode.xml \
+	uri_string.xml \
 	win32reg.xml \
 	zip.xml
 
diff --git a/lib/stdlib/doc/src/ref_man.xml b/lib/stdlib/doc/src/ref_man.xml
index 878a3babc5..68bfddbc71 100644
--- a/lib/stdlib/doc/src/ref_man.xml
+++ b/lib/stdlib/doc/src/ref_man.xml
@@ -93,6 +93,7 @@
   <xi:include href="sys.xml"/>
   <xi:include href="timer.xml"/>
   <xi:include href="unicode.xml"/>
+  <xi:include href="uri_string.xml"/>
   <xi:include href="win32reg.xml"/>
   <xi:include href="zip.xml"/>
 </application>
diff --git a/lib/stdlib/doc/src/specs.xml b/lib/stdlib/doc/src/specs.xml
index 45b207b13d..d559adf9b6 100644
--- a/lib/stdlib/doc/src/specs.xml
+++ b/lib/stdlib/doc/src/specs.xml
@@ -60,6 +60,7 @@
   <xi:include href="../specs/specs_sys.xml"/>
   <xi:include href="../specs/specs_timer.xml"/>
   <xi:include href="../specs/specs_unicode.xml"/>
+  <xi:include href="../specs/specs_uri_string.xml"/>
   <xi:include href="../specs/specs_win32reg.xml"/>
   <xi:include href="../specs/specs_zip.xml"/>
 </specs>
diff --git a/lib/stdlib/doc/src/uri_string.xml b/lib/stdlib/doc/src/uri_string.xml
new file mode 100644
index 0000000000..9ace2b0a05
--- /dev/null
+++ b/lib/stdlib/doc/src/uri_string.xml
@@ -0,0 +1,230 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE erlref SYSTEM "erlref.dtd">
+
+<erlref>
+  <header>
+    <copyright>
+      <year>2017</year><year>2017</year>
+      <holder>Ericsson AB. All Rights Reserved.</holder>
+    </copyright>
+    <legalnotice>
+      Licensed under the Apache License, Version 2.0 (the "License");
+      you may not use this file except in compliance with the License.
+      You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+      Unless required by applicable law or agreed to in writing, software
+      distributed under the License is distributed on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+      See the License for the specific language governing permissions and
+      limitations under the License.
+    </legalnotice>
+
+    <title>uri_string</title>
+    <prepared>Péter Dimitrov</prepared>
+    <docno>1</docno>
+    <date>2017-10-24</date>
+    <rev>A</rev>
+  </header>
+  <module>uri_string</module>
+  <modulesummary>URI processing functions.</modulesummary>
+  <description>
+    <p>This module contains functions for parsing and handling URIs
+    (<url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>).
+    </p>
+    <p>A URI is an identifier consisting of a sequence of characters   matching the syntax
+    rule named <em>URI</em> in <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>.
+    </p>
+    <p>  The generic URI syntax consists of a hierarchical sequence of components referred
+    to as the scheme, authority, path, query, and fragment:</p>
+    <pre>
+    URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+    hier-part   = "//" authority path-abempty
+                   / path-absolute
+                   / path-rootless
+                   / path-empty
+    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+    authority   = [ userinfo "@" ] host [ ":" port ]
+    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+
+    reserved    = gen-delims / sub-delims
+    gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+    sub-delims  = "!" / "$" / "&amp;" / "'" / "(" / ")"
+                / "*" / "+" / "," / ";" / "="
+
+    unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+    </pre><br></br>
+    <p>The interpretation of a URI depends only on the characters used and not on how those
+    characters are represented in a network protocol.</p>
+    <p>The functions implemented by this module cover the following use cases:</p>
+    <list type="bulleted">
+      <item>Parsing URIs into its components and returing a map<br></br>
+      <seealso marker="#parse/1"><c>parse/1</c></seealso>
+      </item>
+      <item>Recomposing a map of URI components into a URI string<br></br>
+      <seealso marker="#recompose/1"><c>recompose/1</c></seealso>
+      </item>
+      <item>Changing inbound binary and percent-encoding of URIs<br></br>
+      <seealso marker="#transcode/2"><c>transcode/2</c></seealso>
+      </item>
+      <item>Transforming URIs into a normalized form<br></br>
+      <seealso marker="#normalize/1"><c>normalize/1</c></seealso>
+      </item>
+    </list>
+    <p>There are four different encodings present during the handling of URIs:</p>
+    <list type="bulleted">
+      <item>Inbound binary encoding in binaries</item>
+      <item>Inbound percent-encoding in lists and binaries</item>
+      <item>Outbound binary encoding in binaries</item>
+      <item>Outbound percent-encoding in lists and binaries</item>
+    </list>
+    <p>Functions with <c>uri_string()</c> argument accept lists, binaries and
+    mixed lists (lists with binary elements) as input type. All of the functions but
+    <c>transcode/2</c> expects input as lists of unicode codepoints, UTF-8 encoded binaries
+    and UTF-8 percent-encoded URI parts ("%C3%B6" corresponds to the unicode character "ö").</p>
+    <p>Unless otherwise specified the return value type and encoding are the same as the input
+    type and encoding. That is, binary input returns binary output, list input returns a list
+    output but mixed input returns list output.</p>
+    <p>In case of lists there is only percent-encoding. In binaries, however, both binary encoding
+    and percent-encoding shall be considered. <c>transcode/2</c> provides the means to convert
+    between the supported encodings, it takes a <c>uri_string()</c> and a list of options
+    specifying inbound and outbound encodings.</p>
+    <p><url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url> does not mandate any specific
+    character encoding and it is usually defined by the protocol or surrounding text. This library
+    takes the same assumption, binary and percent-encoding are handled as one configuration unit,
+    they cannot be set to different values.</p>
+  </description>
+
+  <datatypes>
+    <datatype>
+      <name name="error"/>
+      <desc>
+        <p>Error tuple indicating the type of error. Possible values of the second component:</p>
+	<list type="bulleted">
+	  <item><c>invalid_input</c></item>
+	  <item><c>invalid_map</c></item>
+	  <item><c>invalid_percent_encoding</c></item>
+	  <item><c>invalid_scheme</c></item>
+	  <item><c>invalid_uri</c></item>
+	  <item><c>invalid_utf8</c></item>
+	</list>
+	<p>The third component is a term providing additional information about the
+	cause of the error.</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="uri_map"/>
+      <desc>
+        <p>Map holding the main components of a URI.</p>
+      </desc>
+    </datatype>
+    <datatype>
+      <name name="uri_string"/>
+      <desc>
+        <p>List of unicode codepoints, a UTF-8 encoded binary, or a mix of the two,
+        representing an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>
+	compliant URI (<em>percent-encoded form</em>).
+        A URI is a sequence of characters from a very limited set: the letters of
+        the basic Latin alphabet, digits, and a few special characters.</p>
+      </desc>
+    </datatype>
+  </datatypes>
+
+  <funcs>
+
+    <func>
+      <name name="normalize" arity="1"/>
+      <fsummary>Syntax-based normalization.</fsummary>
+      <desc>
+        <p>Transforms <c><anno>URIString</anno></c> into a normalized form
+	using Syntax-Based Normalization as defined by
+	<url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>.</p>
+	<p>This function implements case normalization, percent-encoding
+	normalization, path segment normalization and scheme based normalization
+	for HTTP(S) with basic support for FTP, SSH, SFTP and TFTP.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>uri_string:normalize("/a/b/c/./../../g").</input>
+"/a/g"
+2> <![CDATA[uri_string:normalize(<<"mid/content=5/../6">>).]]>
+<![CDATA[<<"mid/6">>]]>
+3> uri_string:normalize("http://localhost:80").
+"https://localhost/"
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="parse" arity="1"/>
+      <fsummary>Parse URI into a map.</fsummary>
+      <desc>
+        <p>Parses an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>
+	compliant <c>uri_string()</c> into a <c>uri_map()</c>, that holds the parsed
+	components of the <c>URI</c>.
+	If parsing fails, an error tuple is returned.</p>
+	<p>See also the opposite operation <seealso marker="#recompose/1">
+	<c>recompose/1</c></seealso>.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>uri_string:parse("foo://[email protected]:8042/over/there?name=ferret#nose").</input>
+#{fragment => "nose",host => "example.com",
+  path => "/over/there",port => 8042,query => "name=ferret",
+  scheme => foo,userinfo => "user"}
+2> <![CDATA[uri_string:parse(<<"foo://[email protected]:8042/over/there?name=ferret">>).]]>
+<![CDATA[#{host => <<"example.com">>,path => <<"/over/there">>,
+  port => 8042,query => <<"name=ferret">>,scheme => <<"foo">>,
+  userinfo => <<"user">>}]]>
+	</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="recompose" arity="1"/>
+      <fsummary>Recompose URI.</fsummary>
+      <desc>
+        <p>Creates an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url> compliant
+	<c><anno>URIString</anno></c> (percent-encoded), based on the components of
+	<c><anno>URIMap</anno></c>.
+	If the <c><anno>URIMap</anno></c> is invalid, an error tuple is returned.</p>
+	<p>See also the opposite operation <seealso marker="#parse/1">
+	<c>parse/1</c></seealso>.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input>URIMap = #{fragment => "nose", host => "example.com", path => "/over/there",</input>
+1> port => 8042, query => "name=ferret", scheme => "foo", userinfo => "user"}.
+#{fragment => "top",host => "example.com",
+  path => "/over/there",port => 8042,query => "?name=ferret",
+  scheme => foo,userinfo => "user"}
+
+2> <input>uri_string:recompose(URIMap).</input>
+"foo://example.com:8042/over/there?name=ferret#nose"</pre>
+      </desc>
+    </func>
+
+    <func>
+      <name name="transcode" arity="2"/>
+      <fsummary>Transcode URI.</fsummary>
+      <desc>
+        <p>Transcodes an <url href="https://www.ietf.org/rfc/rfc3986.txt">RFC 3986</url>
+	compliant <c><anno>URIString</anno></c>,
+	where <c><anno>Options</anno></c> is a list of tagged tuples, specifying the inbound
+	(<c>in_encoding</c>) and outbound (<c>out_encoding</c>) encodings. <c>in_encoding</c>
+	and <c>out_encoding</c> specifies both binary encoding and percent-encoding for the
+	input and output data. Mixed encoding, where binary encoding is not the same as
+	percent-encoding, is not supported.
+	If an argument is invalid, an error tuple is returned.</p>
+        <p><em>Example:</em></p>
+        <pre>
+1> <input><![CDATA[uri_string:transcode(<<"foo%00%00%00%F6bar"/utf32>>,]]></input>
+1> [{in_encoding, utf32},{out_encoding, utf8}]).
+<![CDATA[<<"foo%C3%B6bar"/utf8>>]]>
+2> uri_string:transcode("foo%F6bar", [{in_encoding, latin1},
+2> {out_encoding, utf8}]).
+"foo%C3%B6bar"
+	</pre>
+      </desc>
+    </func>
+
+  </funcs>
+</erlref>
diff --git a/lib/stdlib/src/Makefile b/lib/stdlib/src/Makefile
index bf836203ec..8b156929d7 100644
--- a/lib/stdlib/src/Makefile
+++ b/lib/stdlib/src/Makefile
@@ -121,6 +121,7 @@ MODULES= \
 	timer \
 	unicode \
 	unicode_util \
+	uri_string \
 	win32reg \
 	zip
 
diff --git a/lib/stdlib/src/stdlib.app.src b/lib/stdlib/src/stdlib.app.src
index ab0824ca17..5fb48acfab 100644
--- a/lib/stdlib/src/stdlib.app.src
+++ b/lib/stdlib/src/stdlib.app.src
@@ -101,6 +101,7 @@
 	     timer,
 	     unicode,
              unicode_util,
+	     uri_string,
 	     win32reg,
 	     zip]},
   {registered,[timer_server,rsh_starter,take_over_monitor,pool_master,
diff --git a/lib/stdlib/src/uri_string.erl b/lib/stdlib/src/uri_string.erl
new file mode 100644
index 0000000000..22212da222
--- /dev/null
+++ b/lib/stdlib/src/uri_string.erl
@@ -0,0 +1,1842 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+%%
+%% [RFC 3986, Chapter 2.2. Reserved Characters]
+%%
+%%   reserved    = gen-delims / sub-delims
+%%
+%%   gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+%%
+%%   sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
+%%               / "*" / "+" / "," / ";" / "="
+%%
+%%
+%% [RFC 3986, Chapter 2.3. Unreserved Characters]
+%%
+%%   unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+%%
+%%
+%% [RFC 3986, Chapter 3. Syntax Components]
+%%
+%% The generic URI syntax consists of a hierarchical sequence of
+%% components referred to as the scheme, authority, path, query, and
+%% fragment.
+%%
+%%    URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+%%
+%%    hier-part   = "//" authority path-abempty
+%%                   / path-absolute
+%%                   / path-rootless
+%%                   / path-empty
+%%
+%%    The scheme and path components are required, though the path may be
+%%    empty (no characters).  When authority is present, the path must
+%%    either be empty or begin with a slash ("/") character.  When
+%%    authority is not present, the path cannot begin with two slash
+%%    characters ("//").  These restrictions result in five different ABNF
+%%    rules for a path (Section 3.3), only one of which will match any
+%%    given URI reference.
+%%
+%%    The following are two example URIs and their component parts:
+%%
+%%          foo://example.com:8042/over/there?name=ferret#nose
+%%          \_/   \______________/\_________/ \_________/ \__/
+%%           |           |            |            |        |
+%%        scheme     authority       path        query   fragment
+%%           |   _____________________|__
+%%          / \ /                        \
+%%          urn:example:animal:ferret:nose
+%%
+%%
+%% [RFC 3986, Chapter 3.1. Scheme]
+%%
+%% Each URI begins with a scheme name that refers to a specification for
+%% assigning identifiers within that scheme.
+%%
+%%    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+%%
+%%
+%% [RFC 3986, Chapter 3.2. Authority]
+%%
+%% Many URI schemes include a hierarchical element for a naming
+%% authority so that governance of the name space defined by the
+%% remainder of the URI is delegated to that authority (which may, in
+%% turn, delegate it further).
+%%
+%%    authority   = [ userinfo "@" ] host [ ":" port ]
+%%
+%%
+%% [RFC 3986, Chapter 3.2.1. User Information]
+%%
+%% The userinfo subcomponent may consist of a user name and, optionally,
+%% scheme-specific information about how to gain authorization to access
+%% the resource. The user information, if present, is followed by a
+%% commercial at-sign ("@") that delimits it from the host.
+%%
+%%    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+%%
+%%
+%% [RFC 3986, Chapter 3.2.2. Host]
+%%
+%% The host subcomponent of authority is identified by an IP literal
+%% encapsulated within square brackets, an IPv4 address in dotted-
+%% decimal form, or a registered name.
+%%
+%%    host        = IP-literal / IPv4address / reg-name
+%%
+%%    IP-literal = "[" ( IPv6address / IPvFuture  ) "]"
+%%
+%%    IPvFuture  = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+%%
+%%    IPv6address =                            6( h16 ":" ) ls32
+%%                /                       "::" 5( h16 ":" ) ls32
+%%                / [               h16 ] "::" 4( h16 ":" ) ls32
+%%                / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+%%                / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+%%                / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+%%                / [ *4( h16 ":" ) h16 ] "::"              ls32
+%%                / [ *5( h16 ":" ) h16 ] "::"              h16
+%%                / [ *6( h16 ":" ) h16 ] "::"
+%%
+%%    ls32        = ( h16 ":" h16 ) / IPv4address
+%%                ; least-significant 32 bits of address
+%%
+%%    h16         = 1*4HEXDIG
+%%                ; 16 bits of address represented in hexadecimal
+%%
+%%    IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
+%%
+%%    dec-octet   = DIGIT                 ; 0-9
+%%                / %x31-39 DIGIT         ; 10-99
+%%                / "1" 2DIGIT            ; 100-199
+%%                / "2" %x30-34 DIGIT     ; 200-249
+%%                / "25" %x30-35          ; 250-255
+%%
+%%    reg-name    = *( unreserved / pct-encoded / sub-delims )
+%%
+%%
+%% [RFC 3986, Chapter 3.2.2. Port]
+%%
+%% The port subcomponent of authority is designated by an optional port
+%% number in decimal following the host and delimited from it by a
+%% single colon (":") character.
+%%
+%%    port        = *DIGIT
+%%
+%%
+%% [RFC 3986, Chapter 3.3. Path]
+%%
+%% The path component contains data, usually organized in hierarchical
+%% form, that, along with data in the non-hierarchical query component
+%% (Section 3.4), serves to identify a resource within the scope of the
+%% URI's scheme and naming authority (if any).  The path is terminated
+%% by the first question mark ("?") or number sign ("#") character, or
+%% by the end of the URI.
+%%
+%%    path          = path-abempty    ; begins with "/" or is empty
+%%                  / path-absolute   ; begins with "/" but not "//"
+%%                  / path-noscheme   ; begins with a non-colon segment
+%%                  / path-rootless   ; begins with a segment
+%%                  / path-empty      ; zero characters
+%%
+%%    path-abempty  = *( "/" segment )
+%%    path-absolute = "/" [ segment-nz *( "/" segment ) ]
+%%    path-noscheme = segment-nz-nc *( "/" segment )
+%%    path-rootless = segment-nz *( "/" segment )
+%%    path-empty    = 0<pchar>
+%%    segment       = *pchar
+%%    segment-nz    = 1*pchar
+%%    segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+%%                  ; non-zero-length segment without any colon ":"
+%%
+%%    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+%%
+%%
+%% [RFC 3986, Chapter 3.4. Query]
+%%
+%% The query component contains non-hierarchical data that, along with
+%% data in the path component (Section 3.3), serves to identify a
+%% resource within the scope of the URI's scheme and naming authority
+%% (if any).  The query component is indicated by the first question
+%% mark ("?") character and terminated by a number sign ("#") character
+%% or by the end of the URI.
+%%
+%%    query       = *( pchar / "/" / "?" )
+%%
+%%
+%% [RFC 3986, Chapter 3.5. Fragment]
+%%
+%% The fragment identifier component of a URI allows indirect
+%% identification of a secondary resource by reference to a primary
+%% resource and additional identifying information.
+%%
+%%    fragment    = *( pchar / "/" / "?" )
+%%
+%%
+%% [RFC 3986, Chapter 4.1. URI Reference]
+%%
+%% URI-reference is used to denote the most common usage of a resource
+%% identifier.
+%%
+%%    URI-reference = URI / relative-ref
+%%
+%%
+%% [RFC 3986, Chapter 4.2. Relative Reference]
+%%
+%% A relative reference takes advantage of the hierarchical syntax
+%% (Section 1.2.3) to express a URI reference relative to the name space
+%% of another hierarchical URI.
+%%
+%%    relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+%%
+%%    relative-part = "//" authority path-abempty
+%%                  / path-absolute
+%%                  / path-noscheme
+%%                  / path-empty
+%%
+%%
+%% [RFC 3986, Chapter 4.3. Absolute URI]
+%%
+%% Some protocol elements allow only the absolute form of a URI without
+%% a fragment identifier.  For example, defining a base URI for later
+%% use by relative references calls for an absolute-URI syntax rule that
+%% does not allow a fragment.
+%%
+%%    absolute-URI  = scheme ":" hier-part [ "?" query ]
+%%
+-module(uri_string).
+
+%%-------------------------------------------------------------------------
+%% External API
+%%-------------------------------------------------------------------------
+-export([normalize/1, parse/1,
+         recompose/1, transcode/2]).
+-export_type([error/0, uri_map/0, uri_string/0]).
+
+
+%%-------------------------------------------------------------------------
+%% Internal API
+%%-------------------------------------------------------------------------
+-export([is_host/1, is_path/1]).  % suppress warnings
+
+
+%%-------------------------------------------------------------------------
+%% Macros
+%%-------------------------------------------------------------------------
+-define(CHAR(Char), <<Char/utf8>>).
+-define(STRING_EMPTY, <<>>).
+-define(STRING(MatchStr), <<MatchStr/binary>>).
+-define(STRING_REST(MatchStr, Rest), <<MatchStr/utf8, Rest/binary>>).
+
+-define(DEC2HEX(X),
+        if ((X) >= 0) andalso ((X) =< 9) -> (X) + $0;
+           ((X) >= 10) andalso ((X) =< 15) -> (X) + $A - 10
+        end).
+
+-define(HEX2DEC(X),
+        if ((X) >= $0) andalso ((X) =< $9) -> (X) - $0;
+           ((X) >= $A) andalso ((X) =< $F) -> (X) - $A + 10;
+           ((X) >= $a) andalso ((X) =< $f) -> (X) - $a + 10
+        end).
+
+
+%%%=========================================================================
+%%%  API
+%%%=========================================================================
+
+%%-------------------------------------------------------------------------
+%% URI compliant with RFC 3986
+%% ASCII %x21 - %x7A ("!" - "z") except
+%%   %x34    "    double quote
+%%   %x60    <    less than
+%%   %x62    >    greater than
+%%   %x92    \    backslash
+%%   %x94    ^    caret / circumflex
+%%   %x96    `    grave / accent
+%%-------------------------------------------------------------------------
+-type uri_string() :: iodata().
+-type error() :: {error, atom(), term()}.
+
+
+%%-------------------------------------------------------------------------
+%% RFC 3986, Chapter 3. Syntax Components
+%%-------------------------------------------------------------------------
+-type uri_map() ::
+  #{fragment => unicode:chardata(),
+    host => unicode:chardata(),
+    path => unicode:chardata(),
+    port => non_neg_integer() | undefined,
+    query => unicode:chardata(),
+    scheme => unicode:chardata(),
+    userinfo => unicode:chardata()} | #{}.
+
+
+%%-------------------------------------------------------------------------
+%% Normalize URIs
+%%-------------------------------------------------------------------------
+-spec normalize(URIString) -> NormalizedURI when
+      URIString :: uri_string(),
+      NormalizedURI :: uri_string().
+normalize(URIString) ->
+    %% Percent-encoding normalization and case normalization for
+    %% percent-encoded triplets are achieved by running parse and
+    %% recompose on the input URI string.
+    recompose(
+      normalize_path_segment(
+        normalize_scheme_based(
+          normalize_case(
+            parse(URIString))))).
+
+
+%%-------------------------------------------------------------------------
+%% Parse URIs
+%%-------------------------------------------------------------------------
+-spec parse(URIString) -> URIMap when
+      URIString :: uri_string(),
+      URIMap :: uri_map()
+              | error().
+parse(URIString) when is_binary(URIString) ->
+    try parse_uri_reference(URIString, #{})
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end;
+parse(URIString) when is_list(URIString) ->
+    try
+        Binary = unicode:characters_to_binary(URIString),
+        Map = parse_uri_reference(Binary, #{}),
+        convert_mapfields_to_list(Map)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Recompose URIs
+%%-------------------------------------------------------------------------
+-spec recompose(URIMap) -> URIString when
+      URIMap :: uri_map(),
+      URIString :: uri_string()
+                 | error().
+recompose(Map) ->
+    case is_valid_map(Map) of
+        false ->
+            {error, invalid_map, Map};
+        true ->
+            try
+                T0 = update_scheme(Map, empty),
+                T1 = update_userinfo(Map, T0),
+                T2 = update_host(Map, T1),
+                T3 = update_port(Map, T2),
+                T4 = update_path(Map, T3),
+                T5 = update_query(Map, T4),
+                update_fragment(Map, T5)
+            catch
+                throw:{error, Atom, RestData} -> {error, Atom, RestData}
+            end
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Transcode URIs
+%%-------------------------------------------------------------------------
+-spec transcode(URIString, Options) -> Result when
+      URIString :: uri_string(),
+      Options :: [{in_encoding, unicode:encoding()}|{out_encoding, unicode:encoding()}],
+      Result :: uri_string()
+              | error().
+transcode(URIString, Options) when is_binary(URIString) ->
+    try
+        InEnc = proplists:get_value(in_encoding, Options, utf8),
+        OutEnc = proplists:get_value(out_encoding, Options, utf8),
+        List = convert_to_list(URIString, InEnc),
+        Output = transcode(List, [], InEnc, OutEnc),
+        convert_to_binary(Output, utf8, OutEnc)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end;
+transcode(URIString, Options) when is_list(URIString) ->
+    InEnc = proplists:get_value(in_encoding, Options, utf8),
+    OutEnc = proplists:get_value(out_encoding, Options, utf8),
+    Flattened = flatten_list(URIString, InEnc),
+    try transcode(Flattened, [], InEnc, OutEnc)
+    catch
+        throw:{error, Atom, RestData} -> {error, Atom, RestData}
+    end.
+
+
+%%%========================================================================
+%%% Internal functions
+%%%========================================================================
+
+%%-------------------------------------------------------------------------
+%% Converts Map fields to lists
+%%-------------------------------------------------------------------------
+convert_mapfields_to_list(Map) ->
+    Fun = fun (_, V) when is_binary(V) -> unicode:characters_to_list(V);
+              (_, V) -> V end,
+    maps:map(Fun, Map).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 4.1. URI Reference]
+%%
+%% URI-reference is used to denote the most common usage of a resource
+%% identifier.
+%%
+%%    URI-reference = URI / relative-ref
+%%-------------------------------------------------------------------------
+-spec parse_uri_reference(binary(), uri_map()) -> uri_map().
+parse_uri_reference(<<>>, _) -> #{path => <<>>};
+parse_uri_reference(URIString, URI) ->
+    try parse_scheme_start(URIString, URI)
+    catch
+        throw:{_,_,_} ->
+            parse_relative_part(URIString, URI)
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 4.2. Relative Reference]
+%%
+%% A relative reference takes advantage of the hierarchical syntax
+%% (Section 1.2.3) to express a URI reference relative to the name space
+%% of another hierarchical URI.
+%%
+%%    relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+%%
+%%    relative-part = "//" authority path-abempty
+%%                  / path-absolute
+%%                  / path-noscheme
+%%                  / path-empty
+%%-------------------------------------------------------------------------
+-spec parse_relative_part(binary(), uri_map()) -> uri_map().
+parse_relative_part(?STRING_REST("//", Rest), URI) ->
+    %% Parse userinfo - "//" is NOT part of authority
+    try parse_userinfo(Rest, URI) of
+        {T, URI1} ->
+            Userinfo = calculate_parsed_userinfo(Rest, T),
+            URI2 = maybe_add_path(URI1),
+            URI2#{userinfo => decode_userinfo(Userinfo)}
+    catch
+        throw:{_,_,_} ->
+            {T, URI1} = parse_host(Rest, URI),
+            Host = calculate_parsed_host_port(Rest, T),
+            URI2 = maybe_add_path(URI1),
+            URI2#{host => decode_host(remove_brackets(Host))}
+    end;
+parse_relative_part(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-absolute
+    Path = calculate_parsed_part(Rest, T),
+    URI1#{path => decode_path(?STRING_REST($/, Path))};
+parse_relative_part(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    URI2 = maybe_add_path(URI1),
+    URI2#{query => decode_query(Query)};
+parse_relative_part(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    URI2 = maybe_add_path(URI1),
+    URI2#{fragment => decode_fragment(Fragment)};
+parse_relative_part(?STRING_REST(Char, Rest), URI) ->
+    case is_segment_nz_nc(Char) of
+        true ->
+            {T, URI1} = parse_segment_nz_nc(Rest, URI),  % path-noscheme
+            Path = calculate_parsed_part(Rest, T),
+            URI1#{path => decode_path(?STRING_REST(Char, Path))};
+        false -> throw({error,invalid_uri,[Char]})
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.3. Path]
+%%
+%% The path component contains data, usually organized in hierarchical
+%% form, that, along with data in the non-hierarchical query component
+%% (Section 3.4), serves to identify a resource within the scope of the
+%% URI's scheme and naming authority (if any).  The path is terminated
+%% by the first question mark ("?") or number sign ("#") character, or
+%% by the end of the URI.
+%%
+%%    path          = path-abempty    ; begins with "/" or is empty
+%%                  / path-absolute   ; begins with "/" but not "//"
+%%                  / path-noscheme   ; begins with a non-colon segment
+%%                  / path-rootless   ; begins with a segment
+%%                  / path-empty      ; zero characters
+%%
+%%    path-abempty  = *( "/" segment )
+%%    path-absolute = "/" [ segment-nz *( "/" segment ) ]
+%%    path-noscheme = segment-nz-nc *( "/" segment )
+%%    path-rootless = segment-nz *( "/" segment )
+%%    path-empty    = 0<pchar>
+%%    segment       = *pchar
+%%    segment-nz    = 1*pchar
+%%    segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+%%                  ; non-zero-length segment without any colon ":"
+%%
+%%    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%%    path-abempty
+%%-------------------------------------------------------------------------
+-spec parse_segment(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_segment(?STRING_REST($/, Rest), URI) ->
+    parse_segment(Rest, URI);  % segment
+parse_segment(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_segment(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_segment(?STRING_REST(Char, Rest), URI) ->
+    case is_pchar(Char) of
+        true -> parse_segment(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_segment(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%%-------------------------------------------------------------------------
+%%    path-noscheme
+%%-------------------------------------------------------------------------
+-spec parse_segment_nz_nc(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_segment_nz_nc(?STRING_REST($/, Rest), URI) ->
+    parse_segment(Rest, URI);  % segment
+parse_segment_nz_nc(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_segment_nz_nc(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_segment_nz_nc(?STRING_REST(Char, Rest), URI) ->
+    case is_segment_nz_nc(Char) of
+        true -> parse_segment_nz_nc(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_segment_nz_nc(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is pchar.
+-spec is_pchar(char()) -> boolean().
+is_pchar($%) -> true;  % pct-encoded
+is_pchar($:) -> true;
+is_pchar($@) -> true;
+is_pchar(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+%% Check if char is segment_nz_nc.
+-spec is_segment_nz_nc(char()) -> boolean().
+is_segment_nz_nc($%) -> true;  % pct-encoded
+is_segment_nz_nc($@) -> true;
+is_segment_nz_nc(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.1. Scheme]
+%%
+%% Each URI begins with a scheme name that refers to a specification for
+%% assigning identifiers within that scheme.
+%%
+%%    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+%%-------------------------------------------------------------------------
+-spec parse_scheme_start(binary(), uri_map()) -> uri_map().
+parse_scheme_start(?STRING_REST(Char, Rest), URI) ->
+    case is_alpha(Char) of
+        true  -> {T, URI1} = parse_scheme(Rest, URI),
+                 Scheme = calculate_parsed_scheme(Rest, T),
+                 URI2 = maybe_add_path(URI1),
+		 URI2#{scheme => ?STRING_REST(Char, Scheme)};
+        false -> throw({error,invalid_uri,[Char]})
+    end.
+
+%% Add path component if it missing after parsing the URI.
+%% According to the URI specification there is always a
+%% path component in every URI-reference and it can be
+%% empty.
+maybe_add_path(Map) ->
+    case maps:is_key(path, Map) of
+        false ->
+            Map#{path => <<>>};
+        _Else ->
+            Map
+    end.
+
+
+-spec parse_scheme(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_scheme(?STRING_REST($:, Rest), URI) ->
+    {_, URI1} = parse_hier(Rest, URI),
+    {Rest, URI1};
+parse_scheme(?STRING_REST(Char, Rest), URI) ->
+    case is_scheme(Char) of
+        true  -> parse_scheme(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_scheme(?STRING_EMPTY, _URI) ->
+    throw({error,invalid_uri,<<>>}).
+
+
+%% Check if char is allowed in scheme
+-spec is_scheme(char()) -> boolean().
+is_scheme($+) -> true;
+is_scheme($-) -> true;
+is_scheme($.) -> true;
+is_scheme(Char) -> is_alpha(Char) orelse is_digit(Char).
+
+
+%%-------------------------------------------------------------------------
+%%    hier-part   = "//" authority path-abempty
+%%                   / path-absolute
+%%                   / path-rootless
+%%                   / path-empty
+%%-------------------------------------------------------------------------
+-spec parse_hier(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_hier(?STRING_REST("//", Rest), URI) ->
+    % Parse userinfo - "//" is NOT part of authority
+    try parse_userinfo(Rest, URI) of
+        {T, URI1} ->
+            Userinfo = calculate_parsed_userinfo(Rest, T),
+	    {Rest, URI1#{userinfo => decode_userinfo(Userinfo)}}
+    catch
+        throw:{_,_,_} ->
+            {T, URI1} = parse_host(Rest, URI),
+            Host = calculate_parsed_host_port(Rest, T),
+	    {Rest, URI1#{host => decode_host(remove_brackets(Host))}}
+    end;
+parse_hier(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-absolute
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_hier(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_hier(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_hier(?STRING_REST(Char, Rest), URI) ->  % path-rootless
+    case is_pchar(Char) of
+        true ->  % segment_nz
+            {T, URI1} = parse_segment(Rest, URI),
+            Path = calculate_parsed_part(Rest, T),
+            {Rest, URI1#{path => decode_path(?STRING_REST(Char, Path))}};
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_hier(?STRING_EMPTY, URI) ->
+    {<<>>, URI}.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.2. Authority]
+%%
+%% Many URI schemes include a hierarchical element for a naming
+%% authority so that governance of the name space defined by the
+%% remainder of the URI is delegated to that authority (which may, in
+%% turn, delegate it further).
+%%
+%% The authority component is preceded by a double slash ("//") and is
+%% terminated by the next slash ("/"), question mark ("?"), or number
+%% sign ("#") character, or by the end of the URI.
+%%
+%%    authority   = [ userinfo "@" ] host [ ":" port ]
+%%
+%%
+%% [RFC 3986, Chapter 3.2.1. User Information]
+%%
+%% The userinfo subcomponent may consist of a user name and, optionally,
+%% scheme-specific information about how to gain authorization to access
+%% the resource. The user information, if present, is followed by a
+%% commercial at-sign ("@") that delimits it from the host.
+%%
+%%    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+%%-------------------------------------------------------------------------
+-spec parse_userinfo(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_userinfo(?CHAR($@), URI) ->
+    {?STRING_EMPTY, URI#{host => <<>>}};
+parse_userinfo(?STRING_REST($@, Rest), URI) ->
+    {T, URI1} = parse_host(Rest, URI),
+    Host = calculate_parsed_host_port(Rest, T),
+    {Rest, URI1#{host => decode_host(remove_brackets(Host))}};
+parse_userinfo(?STRING_REST(Char, Rest), URI) ->
+    case is_userinfo(Char) of
+        true -> parse_userinfo(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_userinfo(?STRING_EMPTY, _URI) ->
+    %% URI cannot end in userinfo state
+    throw({error,invalid_uri,<<>>}).
+
+
+%% Check if char is allowed in userinfo
+-spec is_userinfo(char()) -> boolean().
+is_userinfo($%) -> true;  % pct-encoded
+is_userinfo($:) -> true;
+is_userinfo(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.2.2. Host]
+%%
+%% The host subcomponent of authority is identified by an IP literal
+%% encapsulated within square brackets, an IPv4 address in dotted-
+%% decimal form, or a registered name.
+%%
+%%    host        = IP-literal / IPv4address / reg-name
+%%
+%%    IP-literal = "[" ( IPv6address / IPvFuture  ) "]"
+%%
+%%    IPvFuture  = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+%%
+%%    IPv6address =                            6( h16 ":" ) ls32
+%%                /                       "::" 5( h16 ":" ) ls32
+%%                / [               h16 ] "::" 4( h16 ":" ) ls32
+%%                / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+%%                / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+%%                / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+%%                / [ *4( h16 ":" ) h16 ] "::"              ls32
+%%                / [ *5( h16 ":" ) h16 ] "::"              h16
+%%                / [ *6( h16 ":" ) h16 ] "::"
+%%
+%%    ls32        = ( h16 ":" h16 ) / IPv4address
+%%                ; least-significant 32 bits of address
+%%
+%%    h16         = 1*4HEXDIG
+%%                ; 16 bits of address represented in hexadecimal
+%%
+%%    IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
+%%
+%%    dec-octet   = DIGIT                 ; 0-9
+%%                / %x31-39 DIGIT         ; 10-99
+%%                / "1" 2DIGIT            ; 100-199
+%%                / "2" %x30-34 DIGIT     ; 200-249
+%%                / "25" %x30-35          ; 250-255
+%%
+%%    reg-name    = *( unreserved / pct-encoded / sub-delims )
+%%-------------------------------------------------------------------------
+-spec parse_host(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_host(?STRING_REST($:, Rest), URI) ->
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_host(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_host(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_host(?STRING_REST($[, Rest), URI) ->
+    parse_ipv6_bin(Rest, [], URI);
+parse_host(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_host(?STRING_REST(Char, Rest), URI) ->
+    case is_digit(Char) of
+        true -> parse_ipv4_bin(Rest, [Char], URI);
+        false -> parse_reg_name(?STRING_REST(Char, Rest), URI)
+    end;
+parse_host(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+-spec parse_reg_name(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_reg_name(?STRING_REST($:, Rest), URI) ->
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_reg_name(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_reg_name(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_reg_name(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_reg_name(?STRING_REST(Char, Rest), URI) ->
+    case is_reg_name(Char) of
+        true -> parse_reg_name(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_reg_name(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+%% Check if char is allowed in reg-name
+-spec is_reg_name(char()) -> boolean().
+is_reg_name($%) -> true;
+is_reg_name(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+
+-spec parse_ipv4_bin(binary(), list(), uri_map()) -> {binary(), uri_map()}.
+parse_ipv4_bin(?STRING_REST($:, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_ipv4_bin(?STRING_REST($/, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_ipv4_bin(?STRING_REST($?, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_ipv4_bin(?STRING_REST($#, Rest), Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_ipv4_bin(?STRING_REST(Char, Rest), Acc, URI) ->
+    case is_ipv4(Char) of
+        true -> parse_ipv4_bin(Rest, [Char|Acc], URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_ipv4_bin(?STRING_EMPTY, Acc, URI) ->
+    _ = validate_ipv4_address(lists:reverse(Acc)),
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is allowed in IPv4 addresses
+-spec is_ipv4(char()) -> boolean().
+is_ipv4($.) -> true;
+is_ipv4(Char) -> is_digit(Char).
+
+-spec validate_ipv4_address(list()) -> list().
+validate_ipv4_address(Addr) ->
+    case inet:parse_ipv4strict_address(Addr) of
+        {ok, _} -> Addr;
+        {error, _} -> throw({error,invalid_uri,Addr})
+    end.
+
+
+-spec parse_ipv6_bin(binary(), list(), uri_map()) -> {binary(), uri_map()}.
+parse_ipv6_bin(?STRING_REST($], Rest), Acc, URI) ->
+    _ = validate_ipv6_address(lists:reverse(Acc)),
+    parse_ipv6_bin_end(Rest, URI);
+parse_ipv6_bin(?STRING_REST(Char, Rest), Acc, URI) ->
+    case is_ipv6(Char) of
+        true -> parse_ipv6_bin(Rest, [Char|Acc], URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_ipv6_bin(?STRING_EMPTY, _Acc, _URI) ->
+    throw({error,invalid_uri,<<>>}).
+
+%% Check if char is allowed in IPv6 addresses
+-spec is_ipv6(char()) -> boolean().
+is_ipv6($:) -> true;
+is_ipv6($.) -> true;
+is_ipv6(Char) -> is_hex_digit(Char).
+
+
+-spec parse_ipv6_bin_end(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_ipv6_bin_end(?STRING_REST($:, Rest), URI) ->
+    {T, URI1} = parse_port(Rest, URI),
+    H = calculate_parsed_host_port(Rest, T),
+    Port = get_port(H),
+    {Rest, URI1#{port => Port}};
+parse_ipv6_bin_end(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_ipv6_bin_end(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_ipv6_bin_end(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_ipv6_bin_end(?STRING_REST(Char, Rest), URI) ->
+    case is_ipv6(Char) of
+        true -> parse_ipv6_bin_end(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_ipv6_bin_end(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+-spec validate_ipv6_address(list()) -> list().
+validate_ipv6_address(Addr) ->
+    case inet:parse_ipv6strict_address(Addr) of
+        {ok, _} -> Addr;
+        {error, _} -> throw({error,invalid_uri,Addr})
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.2.2. Port]
+%%
+%% The port subcomponent of authority is designated by an optional port
+%% number in decimal following the host and delimited from it by a
+%% single colon (":") character.
+%%
+%%    port        = *DIGIT
+%%-------------------------------------------------------------------------
+-spec parse_port(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_port(?STRING_REST($/, Rest), URI) ->
+    {T, URI1} = parse_segment(Rest, URI),  % path-abempty
+    Path = calculate_parsed_part(Rest, T),
+    {Rest, URI1#{path => decode_path(?STRING_REST($/, Path))}};
+parse_port(?STRING_REST($?, Rest), URI) ->
+    {T, URI1} = parse_query(Rest, URI),  % path-empty ?query
+    Query = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{query => decode_query(Query)}};
+parse_port(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),  % path-empty
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_port(?STRING_REST(Char, Rest), URI) ->
+    case is_digit(Char) of
+        true -> parse_port(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_port(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.4. Query]
+%%
+%% The query component contains non-hierarchical data that, along with
+%% data in the path component (Section 3.3), serves to identify a
+%% resource within the scope of the URI's scheme and naming authority
+%% (if any).  The query component is indicated by the first question
+%% mark ("?") character and terminated by a number sign ("#") character
+%% or by the end of the URI.
+%%
+%%    query       = *( pchar / "/" / "?" )
+%%-------------------------------------------------------------------------
+-spec parse_query(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_query(?STRING_REST($#, Rest), URI) ->
+    {T, URI1} = parse_fragment(Rest, URI),
+    Fragment = calculate_parsed_query_fragment(Rest, T),
+    {Rest, URI1#{fragment => decode_fragment(Fragment)}};
+parse_query(?STRING_REST(Char, Rest), URI) ->
+    case is_query(Char) of
+        true -> parse_query(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_query(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is allowed in query
+-spec is_query(char()) -> boolean().
+is_query($/) -> true;
+is_query($?) -> true;
+is_query(Char) -> is_pchar(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 3.5. Fragment]
+%%
+%% The fragment identifier component of a URI allows indirect
+%% identification of a secondary resource by reference to a primary
+%% resource and additional identifying information.
+%%
+%%    fragment    = *( pchar / "/" / "?" )
+%%-------------------------------------------------------------------------
+-spec parse_fragment(binary(), uri_map()) -> {binary(), uri_map()}.
+parse_fragment(?STRING_REST(Char, Rest), URI) ->
+    case is_fragment(Char) of
+        true -> parse_fragment(Rest, URI);
+        false -> throw({error,invalid_uri,[Char]})
+    end;
+parse_fragment(?STRING_EMPTY, URI) ->
+    {?STRING_EMPTY, URI}.
+
+
+%% Check if char is allowed in fragment
+-spec is_fragment(char()) -> boolean().
+is_fragment($/) -> true;
+is_fragment($?) -> true;
+is_fragment(Char) -> is_pchar(Char).
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 2.2. Reserved Characters]
+%%
+%%   reserved    = gen-delims / sub-delims
+%%
+%%   gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+%%
+%%   sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
+%%               / "*" / "+" / "," / ";" / "="
+%%
+%%-------------------------------------------------------------------------
+
+%% Check if char is sub-delim.
+-spec is_sub_delim(char()) -> boolean().
+is_sub_delim($!) -> true;
+is_sub_delim($$) -> true;
+is_sub_delim($&) -> true;
+is_sub_delim($') -> true;
+is_sub_delim($() -> true;
+is_sub_delim($)) -> true;
+
+is_sub_delim($*) -> true;
+is_sub_delim($+) -> true;
+is_sub_delim($,) -> true;
+is_sub_delim($;) -> true;
+is_sub_delim($=) -> true;
+is_sub_delim(_) -> false.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 2.3. Unreserved Characters]
+%%
+%%   unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+%%
+%%-------------------------------------------------------------------------
+-spec is_unreserved(char()) -> boolean().
+is_unreserved($-) -> true;
+is_unreserved($.) -> true;
+is_unreserved($_) -> true;
+is_unreserved($~) -> true;
+is_unreserved(Char) -> is_alpha(Char) orelse is_digit(Char).
+
+-spec is_alpha(char()) -> boolean().
+is_alpha(C)
+  when $A =< C, C =< $Z;
+       $a =< C, C =< $z -> true;
+is_alpha(_) -> false.
+
+-spec is_digit(char()) -> boolean().
+is_digit(C)
+  when $0 =< C, C =< $9 -> true;
+is_digit(_) -> false.
+
+-spec is_hex_digit(char()) -> boolean().
+is_hex_digit(C)
+  when $0 =< C, C =< $9;$a =< C, C =< $f;$A =< C, C =< $F -> true;
+is_hex_digit(_) -> false.
+
+
+%% Remove enclosing brackets from binary
+-spec remove_brackets(binary()) -> binary().
+remove_brackets(<<$[/utf8, Rest/binary>>) ->
+    {H,T} = split_binary(Rest, byte_size(Rest) - 1),
+    case T =:= <<$]/utf8>> of
+        true -> H;
+        false -> Rest
+    end;
+remove_brackets(Addr) -> Addr.
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for calculating the parsed binary.
+%%-------------------------------------------------------------------------
+-spec calculate_parsed_scheme(binary(), binary()) -> binary().
+calculate_parsed_scheme(Input, <<>>) ->
+    strip_last_char(Input, [$:]);
+calculate_parsed_scheme(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+-spec calculate_parsed_part(binary(), binary()) -> binary().
+calculate_parsed_part(Input, <<>>) ->
+    strip_last_char(Input, [$?,$#]);
+calculate_parsed_part(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+-spec calculate_parsed_userinfo(binary(), binary()) -> binary().
+calculate_parsed_userinfo(Input, <<>>) ->
+    strip_last_char(Input, [$?,$#,$@]);
+calculate_parsed_userinfo(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+-spec calculate_parsed_host_port(binary(), binary()) -> binary().
+calculate_parsed_host_port(Input, <<>>) ->
+    strip_last_char(Input, [$:,$?,$#,$/]);
+calculate_parsed_host_port(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+calculate_parsed_query_fragment(Input, <<>>) ->
+    strip_last_char(Input, [$#]);
+calculate_parsed_query_fragment(Input, Unparsed) ->
+    get_parsed_binary(Input, Unparsed).
+
+
+get_port(<<>>) ->
+    undefined;
+get_port(B) ->
+    try binary_to_integer(B)
+    catch
+        error:badarg ->
+            throw({error, invalid_uri, B})
+    end.
+
+
+%% Strip last char if it is in list
+%%
+%% This function is optimized for speed: parse/1 is about 10% faster than
+%% with an alternative implementation based on lists and sets.
+strip_last_char(<<>>, _) -> <<>>;
+strip_last_char(Input, [C0]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end;
+strip_last_char(Input, [C0,C1]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        C1 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end;
+strip_last_char(Input, [C0,C1,C2]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        C1 ->
+            init_binary(Input);
+        C2 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end;
+strip_last_char(Input, [C0,C1,C2,C3]) ->
+    case binary:last(Input) of
+        C0 ->
+            init_binary(Input);
+        C1 ->
+            init_binary(Input);
+        C2 ->
+            init_binary(Input);
+        C3 ->
+            init_binary(Input);
+        _Else ->
+            Input
+    end.
+
+
+%% Get parsed binary
+get_parsed_binary(Input, Unparsed) ->
+    {First, _} = split_binary(Input, byte_size(Input) - byte_size_exl_head(Unparsed)),
+    First.
+
+
+%% Return all bytes of the binary except the last one. The binary must be non-empty.
+init_binary(B) ->
+    {Init, _} =
+        split_binary(B, byte_size(B) - 1),
+    Init.
+
+
+%% Returns the size of a binary exluding the first element.
+%% Used in calls to split_binary().
+-spec byte_size_exl_head(binary()) -> number().
+byte_size_exl_head(<<>>) -> 0;
+byte_size_exl_head(Binary) -> byte_size(Binary) + 1.
+
+
+%%-------------------------------------------------------------------------
+%% [RFC 3986, Chapter 2.1.  Percent-Encoding]
+%%
+%% A percent-encoding mechanism is used to represent a data octet in a
+%% component when that octet's corresponding character is outside the
+%% allowed set or is being used as a delimiter of, or within, the
+%% component.  A percent-encoded octet is encoded as a character
+%% triplet, consisting of the percent character "%" followed by the two
+%% hexadecimal digits representing that octet's numeric value.  For
+%% example, "%20" is the percent-encoding for the binary octet
+%% "00100000" (ABNF: %x20), which in US-ASCII corresponds to the space
+%% character (SP).  Section 2.4 describes when percent-encoding and
+%% decoding is applied.
+%%
+%%   pct-encoded = "%" HEXDIG HEXDIG
+%%-------------------------------------------------------------------------
+-spec decode_userinfo(binary()) -> binary().
+decode_userinfo(Cs) ->
+    check_utf8(decode(Cs, fun is_userinfo/1, <<>>)).
+
+-spec decode_host(binary()) -> binary().
+decode_host(Cs) ->
+    check_utf8(decode(Cs, fun is_host/1, <<>>)).
+
+-spec decode_path(binary()) -> binary().
+decode_path(Cs) ->
+    check_utf8(decode(Cs, fun is_path/1, <<>>)).
+
+-spec decode_query(binary()) -> binary().
+decode_query(Cs) ->
+    check_utf8(decode(Cs, fun is_query/1, <<>>)).
+
+-spec decode_fragment(binary()) -> binary().
+decode_fragment(Cs) ->
+    check_utf8(decode(Cs, fun is_fragment/1, <<>>)).
+
+
+%% Returns Cs if it is utf8 encoded.
+check_utf8(Cs) ->
+    case unicode:characters_to_list(Cs) of
+        {incomplete,_,_} ->
+            throw({error,invalid_utf8,Cs});
+        {error,_,_} ->
+            throw({error,invalid_utf8,Cs});
+        _ -> Cs
+    end.
+
+%%-------------------------------------------------------------------------
+%% Percent-encode
+%%-------------------------------------------------------------------------
+
+%% Only validates as scheme cannot have percent-encoded characters
+-spec encode_scheme(list()|binary()) -> list() | binary().
+encode_scheme([]) ->
+    throw({error,invalid_scheme,""});
+encode_scheme(<<>>) ->
+    throw({error,invalid_scheme,<<>>});
+encode_scheme(Scheme) ->
+    case validate_scheme(Scheme) of
+        true -> Scheme;
+        false -> throw({error,invalid_scheme,Scheme})
+    end.
+
+-spec encode_userinfo(list()|binary()) -> list() | binary().
+encode_userinfo(Cs) ->
+    encode(Cs, fun is_userinfo/1).
+
+-spec encode_host(list()|binary()) -> list() | binary().
+encode_host(Cs) ->
+    case classify_host(Cs) of
+        regname -> Cs;
+        ipv4 -> Cs;
+        ipv6 -> bracket_ipv6(Cs);
+        other -> encode(Cs, fun is_reg_name/1)
+    end.
+
+-spec encode_path(list()|binary()) -> list() | binary().
+encode_path(Cs) ->
+    encode(Cs, fun is_path/1).
+
+-spec encode_query(list()|binary()) -> list() | binary().
+encode_query(Cs) ->
+    encode(Cs, fun is_query/1).
+
+-spec encode_fragment(list()|binary()) -> list() | binary().
+encode_fragment(Cs) ->
+    encode(Cs, fun is_fragment/1).
+
+%%-------------------------------------------------------------------------
+%% Helper funtions for percent-decode
+%%-------------------------------------------------------------------------
+decode(<<$%,C0,C1,Cs/binary>>, Fun, Acc) ->
+    case is_hex_digit(C0) andalso is_hex_digit(C1) of
+        true ->
+            B = ?HEX2DEC(C0)*16+?HEX2DEC(C1),
+            decode(Cs, Fun, <<Acc/binary, B>>);
+        false -> throw({error,invalid_percent_encoding,<<$%,C0,C1>>})
+    end;
+decode(<<C,Cs/binary>>, Fun, Acc) ->
+    case Fun(C) of
+        true -> decode(Cs, Fun, <<Acc/binary, C>>);
+        false -> throw({error,invalid_percent_encoding,<<C,Cs/binary>>})
+    end;
+decode(<<>>, _Fun, Acc) ->
+    Acc.
+
+%% Check if char is allowed in host
+-spec is_host(char()) -> boolean().
+is_host($:) -> true;
+is_host(Char) -> is_unreserved(Char) orelse is_sub_delim(Char).
+
+%% Check if char is allowed in path
+-spec is_path(char()) -> boolean().
+is_path($/) -> true;
+is_path(Char) -> is_pchar(Char).
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for percent-encode
+%%-------------------------------------------------------------------------
+-spec encode(list()|binary(), fun()) -> list() | binary().
+encode(Component, Fun) when is_list(Component) ->
+    B = unicode:characters_to_binary(Component),
+    unicode:characters_to_list(encode(B, Fun, <<>>));
+encode(Component, Fun) when is_binary(Component) ->
+    encode(Component, Fun, <<>>).
+%%
+encode(<<Char/utf8, Rest/binary>>, Fun, Acc) ->
+    C = encode_codepoint_binary(Char, Fun),
+    encode(Rest, Fun, <<Acc/binary,C/binary>>);
+encode(<<Char, Rest/binary>>, _Fun, _Acc) ->
+    throw({error,invalid_input,<<Char,Rest/binary>>});
+encode(<<>>, _Fun, Acc) ->
+    Acc.
+
+
+-spec encode_codepoint_binary(integer(), fun()) -> binary().
+encode_codepoint_binary(C, Fun) ->
+    case Fun(C) of
+        false -> percent_encode_binary(C);
+        true -> <<C>>
+    end.
+
+
+-spec percent_encode_binary(integer()) -> binary().
+percent_encode_binary(Code) ->
+    percent_encode_binary(<<Code/utf8>>, <<>>).
+
+
+percent_encode_binary(<<A:4,B:4,Rest/binary>>, Acc) ->
+    percent_encode_binary(Rest, <<Acc/binary,$%,(?DEC2HEX(A)),(?DEC2HEX(B))>>);
+percent_encode_binary(<<>>, Acc) ->
+    Acc.
+
+
+%%-------------------------------------------------------------------------
+%%-------------------------------------------------------------------------
+validate_scheme([]) -> true;
+validate_scheme([H|T]) ->
+    case is_scheme(H) of
+        true -> validate_scheme(T);
+        false -> false
+    end;
+validate_scheme(<<>>) -> true;
+validate_scheme(<<H, Rest/binary>>) ->
+    case is_scheme(H) of
+        true -> validate_scheme(Rest);
+        false -> false
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Classifies hostname into the following categories:
+%% regname, ipv4 - address does not contain reserved characters to be
+%%           percent-encoded
+%% ipv6 - address does not contain reserved characters but it shall be
+%%        encolsed in brackets
+%% other - address shall be percent-encoded
+%%-------------------------------------------------------------------------
+classify_host([]) -> other;
+classify_host(Addr) when is_binary(Addr) ->
+    A = unicode:characters_to_list(Addr),
+    classify_host_ipv6(A);
+classify_host(Addr) ->
+    classify_host_ipv6(Addr).
+
+classify_host_ipv6(Addr) ->
+    case is_ipv6_address(Addr) of
+        true -> ipv6;
+        false -> classify_host_ipv4(Addr)
+    end.
+
+classify_host_ipv4(Addr) ->
+    case is_ipv4_address(Addr) of
+        true -> ipv4;
+        false -> classify_host_regname(Addr)
+    end.
+
+classify_host_regname([]) -> regname;
+classify_host_regname([H|T]) ->
+    case is_reg_name(H) of
+        true -> classify_host_regname(T);
+        false -> other
+    end.
+
+is_ipv4_address(Addr) ->
+    case inet:parse_ipv4strict_address(Addr) of
+        {ok, _} -> true;
+        {error, _} -> false
+    end.
+
+is_ipv6_address(Addr) ->
+    case inet:parse_ipv6strict_address(Addr) of
+        {ok, _} -> true;
+        {error, _} -> false
+    end.
+
+bracket_ipv6(Addr) when is_binary(Addr) ->
+    concat(<<$[,Addr/binary>>,<<$]>>);
+bracket_ipv6(Addr) when is_list(Addr) ->
+    [$[|Addr] ++ "]".
+
+
+%%-------------------------------------------------------------------------
+%% Helper funtions for recompose
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%% Checks if input Map has valid combination of fields that can be
+%% recomposed into a URI.
+%%
+%% The implementation is based on a decision tree that fulfills the
+%% following rules:
+%%   - 'path' shall always be present in the input map
+%%       URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+%%       hier-part   = "//" authority path-abempty
+%%                      / path-absolute
+%%                      / path-rootless
+%%                      / path-empty
+%%   - 'host' shall be present in the input map when 'path' starts with
+%%     two slashes ("//")
+%%       path          = path-abempty    ; begins with "/" or is empty
+%%                     / path-absolute   ; begins with "/" but not "//"
+%%                     / path-noscheme   ; begins with a non-colon segment
+%%                     / path-rootless   ; begins with a segment
+%%                     / path-empty      ; zero characters
+%%       path-abempty  = *( "/" segment )
+%%       segment       = *pchar
+%%   - 'host' shall be present if userinfo or port is present in input map
+%%       authority   = [ userinfo "@" ] host [ ":" port ]
+%%   - All fields shall be valid (scheme, userinfo, host, port, path, query
+%%     or fragment).
+%%-------------------------------------------------------------------------
+is_valid_map(#{path := Path} = Map) ->
+    ((starts_with_two_slash(Path) andalso is_valid_map_host(Map))
+     orelse
+       (maps:is_key(userinfo, Map) andalso is_valid_map_host(Map))
+     orelse
+       (maps:is_key(port, Map) andalso is_valid_map_host(Map))
+     orelse
+     all_fields_valid(Map));
+is_valid_map(#{}) ->
+    false.
+
+
+is_valid_map_host(Map) ->
+    maps:is_key(host, Map) andalso all_fields_valid(Map).
+
+
+all_fields_valid(Map) ->
+    Fun = fun(scheme, _, Acc) -> Acc;
+             (userinfo, _, Acc) -> Acc;
+             (host, _, Acc) -> Acc;
+             (port, _, Acc) -> Acc;
+             (path, _, Acc) -> Acc;
+             (query, _, Acc) -> Acc;
+             (fragment, _, Acc) -> Acc;
+             (_, _, _) -> false
+          end,
+    maps:fold(Fun, true, Map).
+
+
+starts_with_two_slash([$/,$/|_]) ->
+    true;
+starts_with_two_slash(?STRING_REST("//", _)) ->
+    true;
+starts_with_two_slash(_) -> false.
+
+
+update_scheme(#{scheme := Scheme}, _) ->
+    add_colon_postfix(encode_scheme(Scheme));
+update_scheme(#{}, _) ->
+    empty.
+
+
+update_userinfo(#{userinfo := Userinfo}, empty) ->
+    add_auth_prefix(encode_userinfo(Userinfo));
+update_userinfo(#{userinfo := Userinfo}, URI) ->
+    concat(URI,add_auth_prefix(encode_userinfo(Userinfo)));
+update_userinfo(#{}, empty) ->
+    empty;
+update_userinfo(#{}, URI) ->
+    URI.
+
+
+update_host(#{host := Host}, empty) ->
+    add_auth_prefix(encode_host(Host));
+update_host(#{host := Host} = Map, URI) ->
+    concat(URI,add_host_prefix(Map, encode_host(Host)));
+update_host(#{}, empty) ->
+    empty;
+update_host(#{}, URI) ->
+    URI.
+
+
+%% URI cannot be empty for ports. E.g. ":8080" is not a valid URI
+update_port(#{port := undefined}, URI) ->
+    concat(URI, <<":">>);
+update_port(#{port := Port}, URI) ->
+    concat(URI,add_colon(encode_port(Port)));
+update_port(#{}, URI) ->
+    URI.
+
+
+update_path(#{path := Path}, empty) ->
+    encode_path(Path);
+update_path(#{path := Path}, URI) ->
+    concat(URI,encode_path(Path));
+update_path(#{}, empty) ->
+    empty;
+update_path(#{}, URI) ->
+    URI.
+
+
+update_query(#{query := Query}, empty) ->
+    encode_query(Query);
+update_query(#{query := Query}, URI) ->
+    concat(URI,add_question_mark(encode_query(Query)));
+update_query(#{}, empty) ->
+    empty;
+update_query(#{}, URI) ->
+    URI.
+
+
+update_fragment(#{fragment := Fragment}, empty) ->
+    add_hashmark(encode_fragment(Fragment));
+update_fragment(#{fragment := Fragment}, URI) ->
+    concat(URI,add_hashmark(encode_fragment(Fragment)));
+update_fragment(#{}, empty) ->
+    "";
+update_fragment(#{}, URI) ->
+    URI.
+
+%%-------------------------------------------------------------------------
+%% Concatenates its arguments that can be lists and binaries.
+%% The result is a list if at least one of its argument is a list and
+%% binary otherwise.
+%%-------------------------------------------------------------------------
+concat(A, B) when is_binary(A), is_binary(B) ->
+    <<A/binary, B/binary>>;
+concat(A, B) when is_binary(A), is_list(B) ->
+    unicode:characters_to_list(A) ++ B;
+concat(A, B) when is_list(A) ->
+    A ++ maybe_to_list(B).
+
+add_hashmark(Comp) when is_binary(Comp) ->
+    <<$#, Comp/binary>>;
+add_hashmark(Comp) when is_list(Comp) ->
+    [$#|Comp].
+
+add_question_mark(Comp) when is_binary(Comp) ->
+    <<$?, Comp/binary>>;
+add_question_mark(Comp) when is_list(Comp) ->
+    [$?|Comp].
+
+add_colon(Comp) when is_binary(Comp) ->
+    <<$:, Comp/binary>>.
+
+add_colon_postfix(Comp) when is_binary(Comp) ->
+    <<Comp/binary,$:>>;
+add_colon_postfix(Comp) when is_list(Comp) ->
+    Comp ++ ":".
+
+add_auth_prefix(Comp) when is_binary(Comp) ->
+    <<"//", Comp/binary>>;
+add_auth_prefix(Comp) when is_list(Comp) ->
+    [$/,$/|Comp].
+
+add_host_prefix(#{userinfo := _}, Host) when is_binary(Host) ->
+    <<$@,Host/binary>>;
+add_host_prefix(#{}, Host) when is_binary(Host) ->
+    <<"//",Host/binary>>;
+add_host_prefix(#{userinfo := _}, Host) when is_list(Host) ->
+    [$@|Host];
+add_host_prefix(#{}, Host) when is_list(Host) ->
+    [$/,$/|Host].
+
+maybe_to_list(Comp) when is_binary(Comp) -> unicode:characters_to_list(Comp);
+maybe_to_list(Comp) -> Comp.
+
+encode_port(Port) ->
+    integer_to_binary(Port).
+
+%%-------------------------------------------------------------------------
+%% Helper functions for transcode
+%%-------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%% uri_string:transcode(<<"x%00%00%00%F6"/utf32>>).
+%% 1. Convert (transcode/2) input to list form (list of unicode codepoints)
+%%    "x%00%00%00%F6"
+%% 2. Accumulate characters until percent-encoded segment (transcode/4).
+%%    Acc = "x"
+%% 3. Convert percent-encoded triplets to binary form (transcode_pct/4)
+%%    <<0,0,0,246>>
+%% 4. Transcode in-encoded binary to out-encoding (utf32 -> utf8):
+%%    <<195,182>>
+%% 5. Percent-encode out-encoded binary:
+%%    <<"%C3%B6"/utf8>> = <<37,67,51,37,66,54>>
+%% 6. Convert binary to list form, reverse it and append the accumulator
+%%    "6B%3C%" + "x"
+%% 7. Reverse Acc and return it
+%%-------------------------------------------------------------------------
+transcode([$%,_C0,_C1|_Rest] = L, Acc, InEnc, OutEnc) ->
+    transcode_pct(L, Acc, <<>>, InEnc, OutEnc);
+transcode([_C|_Rest] = L, Acc, InEnc, OutEnc) ->
+    transcode(L, Acc, [], InEnc, OutEnc).
+%%
+transcode([$%,_C0,_C1|_Rest] = L, Acc, List, InEncoding, OutEncoding) ->
+    transcode_pct(L, List ++ Acc, <<>>, InEncoding, OutEncoding);
+transcode([C|Rest], Acc, List, InEncoding, OutEncoding) ->
+    transcode(Rest, Acc, [C|List], InEncoding, OutEncoding);
+transcode([], Acc, List, _InEncoding, _OutEncoding) ->
+    lists:reverse(List ++ Acc).
+
+
+%% Transcode percent-encoded segment
+transcode_pct([$%,C0,C1|Rest] = L, Acc, B, InEncoding, OutEncoding) ->
+    case is_hex_digit(C0) andalso is_hex_digit(C1) of
+        true ->
+            Int = ?HEX2DEC(C0)*16+?HEX2DEC(C1),
+            transcode_pct(Rest, Acc, <<B/binary, Int>>, InEncoding, OutEncoding);
+        false -> throw({error, invalid_percent_encoding,L})
+    end;
+transcode_pct([_C|_Rest] = L, Acc, B, InEncoding, OutEncoding) ->
+    OutBinary = convert_to_binary(B, InEncoding, OutEncoding),
+    PctEncUtf8 = percent_encode_segment(OutBinary),
+    Out = lists:reverse(convert_to_list(PctEncUtf8, utf8)),
+    transcode(L, Out ++ Acc, [], InEncoding, OutEncoding);
+transcode_pct([], Acc, B, InEncoding, OutEncoding) ->
+    OutBinary = convert_to_binary(B, InEncoding, OutEncoding),
+    PctEncUtf8 = percent_encode_segment(OutBinary),
+    Out = convert_to_list(PctEncUtf8, utf8),
+    lists:reverse(Acc) ++ Out.
+
+
+%% Convert to binary
+convert_to_binary(Binary, InEncoding, OutEncoding) ->
+    case unicode:characters_to_binary(Binary, InEncoding, OutEncoding) of
+        {error, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        {incomplete, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        Result ->
+            Result
+    end.
+
+
+%% Convert to list
+convert_to_list(Binary, InEncoding) ->
+    case unicode:characters_to_list(Binary, InEncoding) of
+        {error, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        {incomplete, _List, RestData} ->
+            throw({error, invalid_input, RestData});
+        Result ->
+            Result
+    end.
+
+
+%% Flatten input list
+flatten_list([], _) ->
+    [];
+flatten_list(L, InEnc) ->
+    flatten_list(L, InEnc, []).
+%%
+flatten_list([H|T], InEnc, Acc) when is_binary(H) ->
+    L = convert_to_list(H, InEnc),
+    flatten_list(T, InEnc, lists:reverse(L) ++ Acc);
+flatten_list([H|T], InEnc, Acc) when is_list(H) ->
+    flatten_list(H ++ T, InEnc, Acc);
+flatten_list([H|T], InEnc, Acc) ->
+    flatten_list(T, InEnc, [H|Acc]);
+flatten_list([], _InEnc, Acc) ->
+    lists:reverse(Acc);
+flatten_list(Arg, _, _) ->
+    throw({error, invalid_input, Arg}).
+
+
+percent_encode_segment(Segment) ->
+    percent_encode_binary(Segment, <<>>).
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions for normalize
+%%-------------------------------------------------------------------------
+
+%% 6.2.2.1.  Case Normalization
+normalize_case(#{scheme := Scheme, host := Host} = Map) ->
+    Map#{scheme => to_lower(Scheme),
+         host => to_lower(Host)};
+normalize_case(#{host := Host} = Map) ->
+    Map#{host => to_lower(Host)};
+normalize_case(#{scheme := Scheme} = Map) ->
+    Map#{scheme => to_lower(Scheme)};
+normalize_case(#{} = Map) ->
+    Map.
+
+
+to_lower(Cs) when is_list(Cs) ->
+    B = convert_to_binary(Cs, utf8, utf8),
+    convert_to_list(to_lower(B), utf8);
+to_lower(Cs) when is_binary(Cs) ->
+    to_lower(Cs, <<>>).
+%%
+to_lower(<<C,Cs/binary>>, Acc) when $A =< C, C =< $Z ->
+    to_lower(Cs, <<Acc/binary,(C + 32)>>);
+to_lower(<<C,Cs/binary>>, Acc) ->
+    to_lower(Cs, <<Acc/binary,C>>);
+to_lower(<<>>, Acc) ->
+    Acc.
+
+
+%% 6.2.2.3. Path Segment Normalization
+%% 5.2.4.   Remove Dot Segments
+normalize_path_segment(Map) ->
+    Path = maps:get(path, Map, undefined),
+    Map#{path => remove_dot_segments(Path)}.
+
+
+remove_dot_segments(Path) when is_binary(Path) ->
+    remove_dot_segments(Path, <<>>);
+remove_dot_segments(Path) when is_list(Path) ->
+    B = convert_to_binary(Path, utf8, utf8),
+    B1 = remove_dot_segments(B, <<>>),
+    convert_to_list(B1, utf8).
+%%
+remove_dot_segments(<<>>, Output) ->
+    Output;
+remove_dot_segments(<<"../",T/binary>>, Output) ->
+    remove_dot_segments(T, Output);
+remove_dot_segments(<<"./",T/binary>>, Output) ->
+    remove_dot_segments(T, Output);
+remove_dot_segments(<<"/./",T/binary>>, Output) ->
+    remove_dot_segments(<<$/,T/binary>>, Output);
+remove_dot_segments(<<"/.">>, Output) ->
+    remove_dot_segments(<<$/>>, Output);
+remove_dot_segments(<<"/../",T/binary>>, Output) ->
+    Out1 = remove_last_segment(Output),
+    remove_dot_segments(<<$/,T/binary>>, Out1);
+remove_dot_segments(<<"/..">>, Output) ->
+    Out1 = remove_last_segment(Output),
+    remove_dot_segments(<<$/>>, Out1);
+remove_dot_segments(<<$.>>, Output) ->
+    remove_dot_segments(<<>>, Output);
+remove_dot_segments(<<"..">>, Output) ->
+    remove_dot_segments(<<>>, Output);
+remove_dot_segments(Input, Output) ->
+    {First, Rest} = first_path_segment(Input),
+    remove_dot_segments(Rest, <<Output/binary,First/binary>>).
+
+
+first_path_segment(Input) ->
+    F = first_path_segment(Input, <<>>),
+    split_binary(Input, byte_size(F)).
+%%
+first_path_segment(<<$/,T/binary>>, Acc) ->
+    first_path_segment_end(<<T/binary>>, <<Acc/binary,$/>>);
+first_path_segment(<<C,T/binary>>, Acc) ->
+    first_path_segment_end(<<T/binary>>, <<Acc/binary,C>>).
+
+
+first_path_segment_end(<<>>, Acc) ->
+    Acc;
+first_path_segment_end(<<$/,_/binary>>, Acc) ->
+    Acc;
+first_path_segment_end(<<C,T/binary>>, Acc) ->
+    first_path_segment_end(<<T/binary>>, <<Acc/binary,C>>).
+
+
+remove_last_segment(<<>>) ->
+    <<>>;
+remove_last_segment(B) ->
+    {Init, Last} = split_binary(B, byte_size(B) - 1),
+    case Last of
+        <<$/>> ->
+            Init;
+        _Char ->
+            remove_last_segment(Init)
+    end.
+
+
+%% RFC 3986, 6.2.3.  Scheme-Based Normalization
+normalize_scheme_based(Map) ->
+    Scheme = maps:get(scheme, Map, undefined),
+    Port = maps:get(port, Map, undefined),
+    Path= maps:get(path, Map, undefined),
+    normalize_scheme_based(Map, Scheme, Port, Path).
+%%
+normalize_scheme_based(Map, Scheme, Port, Path)
+  when Scheme =:= "http"; Scheme =:= <<"http">> ->
+    normalize_http(Map, Port, Path);
+normalize_scheme_based(Map, Scheme, Port, Path)
+  when Scheme =:= "https"; Scheme =:= <<"https">> ->
+    normalize_https(Map, Port, Path);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "ftp"; Scheme =:= <<"ftp">> ->
+    normalize_ftp(Map, Port);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "ssh"; Scheme =:= <<"ssh">> ->
+    normalize_ssh_sftp(Map, Port);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "sftp"; Scheme =:= <<"sftp">> ->
+    normalize_ssh_sftp(Map, Port);
+normalize_scheme_based(Map, Scheme, Port, _Path)
+  when Scheme =:= "tftp"; Scheme =:= <<"tftp">> ->
+    normalize_tftp(Map, Port);
+normalize_scheme_based(Map, _, _, _) ->
+    Map.
+
+
+normalize_http(Map, Port, Path) ->
+    M1 = normalize_port(Map, Port, 80),
+    normalize_http_path(M1, Path).
+
+
+normalize_https(Map, Port, Path) ->
+    M1 = normalize_port(Map, Port, 443),
+    normalize_http_path(M1, Path).
+
+
+normalize_ftp(Map, Port) ->
+    normalize_port(Map, Port, 21).
+
+
+normalize_ssh_sftp(Map, Port) ->
+    normalize_port(Map, Port, 22).
+
+
+normalize_tftp(Map, Port) ->
+    normalize_port(Map, Port, 69).
+
+
+normalize_port(Map, Port, Default) ->
+    case Port of
+        Default ->
+            maps:remove(port, Map);
+        _Else ->
+            Map
+    end.
+
+
+normalize_http_path(Map, Path) ->
+    case Path of
+        "" ->
+            Map#{path => "/"};
+        <<>> ->
+            Map#{path => <<"/">>};
+        _Else ->
+            Map
+    end.
diff --git a/lib/stdlib/test/Makefile b/lib/stdlib/test/Makefile
index 523cb95065..8490770f3d 100644
--- a/lib/stdlib/test/Makefile
+++ b/lib/stdlib/test/Makefile
@@ -87,6 +87,7 @@ MODULES= \
 	timer_simple_SUITE \
 	unicode_SUITE \
 	unicode_util_SUITE \
+	uri_string_SUITE \
 	win32reg_SUITE \
 	y2k_SUITE \
 	select_SUITE \
diff --git a/lib/stdlib/test/property_test/README b/lib/stdlib/test/property_test/README
new file mode 100644
index 0000000000..57602bf719
--- /dev/null
+++ b/lib/stdlib/test/property_test/README
@@ -0,0 +1,12 @@
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%                                                             %%%
+%%%                       WARNING                               %%%
+%%%                                                             %%%
+%%% This is experimental code which may be changed or removed   %%%
+%%%               anytime without any warning.                  %%%
+%%%                                                             %%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+The test in this directory are written assuming that the user has a QuickCheck license.  They are to be run manually.  Some may be possible to be run with other tools, e.g. PropEr.
+
diff --git a/lib/stdlib/test/property_test/uri_string_recompose.erl b/lib/stdlib/test/property_test/uri_string_recompose.erl
new file mode 100644
index 0000000000..e51a671172
--- /dev/null
+++ b/lib/stdlib/test/property_test/uri_string_recompose.erl
@@ -0,0 +1,361 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(uri_string_recompose).
+
+-compile(export_all).
+
+-proptest(eqc).
+-proptest([triq,proper]).
+
+-ifndef(EQC).
+-ifndef(PROPER).
+-ifndef(TRIQ).
+-define(EQC,true).
+-endif.
+-endif.
+-endif.
+
+-ifdef(EQC).
+-include_lib("eqc/include/eqc.hrl").
+-define(MOD_eqc,eqc).
+
+-else.
+-ifdef(PROPER).
+-include_lib("proper/include/proper.hrl").
+-define(MOD_eqc,proper).
+
+-else.
+-ifdef(TRIQ).
+-define(MOD_eqc,triq).
+-include_lib("triq/include/triq.hrl").
+
+-endif.
+-endif.
+-endif.
+
+
+-define(STRING_REST(MatchStr, Rest), <<MatchStr/utf8, Rest/binary>>).
+
+-define(SCHEME, {scheme, scheme()}).
+-define(USER, {userinfo, unicode()}).
+-define(HOST, {host, host_map()}).
+-define(PORT, {port, port()}).
+-define(PATH_ABE, {path, path_abempty_map()}).
+-define(PATH_ABS, {path, path_absolute_map()}).
+-define(PATH_NOS, {path, path_noscheme_map()}).
+-define(PATH_ROO, {path, path_rootless_map()}).
+-define(PATH_EMP, {path, path_empty_map()}).
+-define(QUERY, {query, query_map()}).
+-define(FRAGMENT, {fragment, fragment_map()}).
+
+
+%%%========================================================================
+%%% Properties
+%%%========================================================================
+
+prop_recompose() ->
+    ?FORALL(Map, map(),
+            Map =:= uri_string:parse(uri_string:recompose(Map))
+           ).
+
+%% Stats
+prop_map_key_length_collect() ->
+    ?FORALL(List, map(),
+            collect(length(maps:keys(List)), true)).
+
+prop_map_collect() ->
+    ?FORALL(List, map(),
+            collect(lists:sort(maps:keys(List)), true)).
+
+prop_scheme_collect() ->
+    ?FORALL(List, scheme(),
+            collect(length(List), true)).
+
+
+%%%========================================================================
+%%% Generators
+%%%========================================================================
+
+map() ->
+    ?LET(Gen, comp_proplist(), proplist_to_map(Gen)).
+
+comp_proplist() ->
+    frequency([
+               {2, [?SCHEME,?PATH_ABS]},
+               {2, [?SCHEME,?PATH_ROO]},
+               {2, [?SCHEME,?PATH_EMP]},
+               {2, [?SCHEME,?HOST,?PATH_ABE]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE]},
+
+               {2, [?PATH_ABS]},
+               {2, [?PATH_NOS]},
+               {2, [?PATH_EMP]},
+               {2, [?HOST,?PATH_ABE]},
+               {2, [?USER,?HOST,?PATH_ABE]},
+               {2, [?HOST,?PORT,?PATH_ABE]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE]},
+
+
+               {2, [?SCHEME,?PATH_ABS,?QUERY]},
+               {2, [?SCHEME,?PATH_ROO,?QUERY]},
+               {2, [?SCHEME,?PATH_EMP,?QUERY]},
+               {2, [?SCHEME,?HOST,?PATH_ABE,?QUERY]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE,?QUERY]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE,?QUERY]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE,?QUERY]},
+
+               {2, [?PATH_ABS,?QUERY]},
+               {2, [?PATH_NOS,?QUERY]},
+               {2, [?PATH_EMP,?QUERY]},
+               {2, [?HOST,?PATH_ABE,?QUERY]},
+               {2, [?USER,?HOST,?PATH_ABE,?QUERY]},
+               {2, [?HOST,?PORT,?PATH_ABE,?QUERY]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE,?QUERY]},
+
+
+               {2, [?SCHEME,?PATH_ABS,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_ROO,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_EMP,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+
+               {2, [?PATH_ABS,?FRAGMENT]},
+               {2, [?PATH_NOS,?FRAGMENT]},
+               {2, [?PATH_EMP,?FRAGMENT]},
+               {2, [?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?USER,?HOST,?PATH_ABE,?FRAGMENT]},
+               {2, [?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE,?FRAGMENT]},
+
+
+               {2, [?SCHEME,?PATH_ABS,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_ROO,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?PATH_EMP,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?SCHEME,?USER,?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]},
+
+               {2, [?PATH_ABS,?QUERY,?FRAGMENT]},
+               {2, [?PATH_NOS,?QUERY,?FRAGMENT]},
+               {2, [?PATH_EMP,?QUERY,?FRAGMENT]},
+               {2, [?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?USER,?HOST,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]},
+               {2, [?USER,?HOST,?PORT,?PATH_ABE,?QUERY,?FRAGMENT]}
+              ]).
+
+
+%%-------------------------------------------------------------------------
+%% Path
+%%-------------------------------------------------------------------------
+path_abempty_map() ->
+    frequency([{90, path_abe_map()},
+               {10, path_empty_map()}]).
+
+path_abe_map() ->
+    ?SIZED(Length, path_abe_map(Length, [])).
+%%
+path_abe_map(0, Segments) ->
+    ?LET(Gen, Segments, lists:append(Gen));
+path_abe_map(N, Segments) ->
+    path_abe_map(N-1, [slash(),segment()|Segments]).
+
+
+path_absolute_map() ->
+    ?SIZED(Length, path_absolute_map(Length, [])).
+%%
+path_absolute_map(0, Segments) ->
+    ?LET(Gen, [slash(),segment_nz()|Segments], lists:append(Gen));
+path_absolute_map(N, Segments) ->
+    path_absolute_map(N-1, [slash(),segment()|Segments]).
+
+
+path_noscheme_map() ->
+    ?SIZED(Length, path_noscheme_map(Length, [])).
+%%
+path_noscheme_map(0, Segments) ->
+    ?LET(Gen, [segment_nz_nc()|Segments], lists:append(Gen));
+path_noscheme_map(N, Segments) ->
+    path_noscheme_map(N-1, [slash(),segment()|Segments]).
+
+path_rootless_map() ->
+    ?SIZED(Length, path_rootless_map(Length, [])).
+%%
+path_rootless_map(0, Segments) ->
+    ?LET(Gen, [segment_nz()|Segments], lists:append(Gen));
+path_rootless_map(N, Segments) ->
+    path_rootless_map(N-1, [slash(),segment()|Segments]).
+
+
+segment_nz() ->
+    non_empty(segment()).
+
+segment_nz_nc() ->
+    non_empty(list(frequency([{30, unreserved()},
+                              {10, sub_delims()},
+                              {10, unicode_char()},
+                              {5, oneof([$@])}
+                             ]))).
+
+
+segment() ->
+    list(frequency([{30, unreserved()},
+                    {10, sub_delims()},
+                    {10, unicode_char()},
+                    {5, oneof([$:, $@])}
+                   ])).
+
+slash() ->
+    "/".
+
+path_empty_map() ->
+    "".
+
+
+%%-------------------------------------------------------------------------
+%% Path
+%%-------------------------------------------------------------------------
+host_map() ->
+    frequency([{30, reg_name()},
+               {30, ip_address()}
+              ]).
+
+
+reg_name() ->
+    list(frequency([{30, alpha()},
+                              {10, sub_delims()},
+                              {10, unicode_char()}
+                             ])).
+
+ip_address() ->
+    oneof(["127.0.0.1", "::127.0.0.1",
+           "2001:0db8:0000:0000:0000:0000:1428:07ab",
+           "2001:0db8:0000:0000:0000::1428:07ab",
+           "2001:0db8:0:0:0:0:1428:07ab",
+           "2001:0db8:0::0:1428:07ab"]).
+
+%% Generating only reg-names
+host_uri() ->
+    non_empty(list(frequency([{30, unreserved()},
+                              {10, sub_delims()},
+                              {10, pct_encoded()}
+                             ]))).
+
+%%-------------------------------------------------------------------------
+%% Port, Query, Fragment
+%%-------------------------------------------------------------------------
+port() ->
+    frequency([{10, undefined},
+               {10, range(1,65535)}
+              ]).
+
+query_map() ->
+    unicode().
+
+
+query_uri() ->
+    [$?| non_empty(list(frequency([{20, pchar()},
+                                   {5, oneof([$/, $?])} % punctuation
+                                  ])))].
+
+fragment_map() ->
+    unicode().
+
+fragment_uri() ->
+    [$?| non_empty(list(frequency([{20, pchar()},
+                                   {5, oneof([$/, $?])} % punctuation
+                                  ])))].
+
+
+%%-------------------------------------------------------------------------
+%% Scheme
+%%-------------------------------------------------------------------------
+scheme() ->
+    ?SIZED(Length, scheme_start(Length, [])).
+%%
+scheme_start(0, L) ->
+    ?LET(Gen, L, lists:reverse(Gen));
+scheme_start(N, L) ->
+    scheme(N-1,[alpha()|L]).
+
+scheme(0, L) ->
+    ?LET(Gen, L, lists:reverse(Gen));
+scheme(N, L) ->
+    scheme(N-1, [scheme_char()|L]).
+
+
+%%-------------------------------------------------------------------------
+%% Misc
+%%-------------------------------------------------------------------------
+unicode() ->
+    list(frequency([{20, alpha()},                    % alpha
+               {10, digit()},                    % digit
+               {10, unicode_char()}              % unicode
+              ])).
+
+scheme_char() ->
+    frequency([{20, alpha()},                    % alpha
+               {20, digit()},                    % digit
+               {5, oneof([$+, $-, $.])}          % punctuation
+              ]).
+
+sub_delims() ->
+    oneof([$!, $$, $&, $', $(, $),
+           $*, $+, $,,$;, $=]).
+
+pchar() ->
+    frequency([{20, unreserved()},
+               {5, pct_encoded()},
+               {5, sub_delims()},
+               {1, oneof([$:, $@])}              % punctuation
+              ]).
+
+unreserved() ->
+    frequency([{20, alpha()},
+               {5, digit()},
+               {1, oneof([$-, $., $_, $~])}      % punctuation
+              ]).
+
+unicode_char() ->
+    range(913, 1023).
+
+alpha() ->
+    frequency([{20, range($a, $z)},              % letters
+               {20, range($A, $Z)}]).            % letters
+
+digit() ->
+    range($0, $9).                               % numbers
+
+pct_encoded() ->
+    oneof(["%C3%A4", "%C3%A5", "%C3%B6"]).
+
+
+%%%========================================================================
+%%% Helpers
+%%%========================================================================
+proplist_to_map(L) ->
+    lists:foldl(fun({K,V},M) -> M#{K => V};
+                  (_,M) -> M
+               end, #{}, L).
diff --git a/lib/stdlib/test/uri_string_SUITE.erl b/lib/stdlib/test/uri_string_SUITE.erl
new file mode 100644
index 0000000000..c625da56c6
--- /dev/null
+++ b/lib/stdlib/test/uri_string_SUITE.erl
@@ -0,0 +1,844 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(uri_string_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+
+-export([all/0, suite/0,groups/0,
+         normalize/1,
+         parse_binary_fragment/1, parse_binary_host/1, parse_binary_host_ipv4/1,
+         parse_binary_host_ipv6/1,
+         parse_binary_path/1, parse_binary_pct_encoded_fragment/1, parse_binary_pct_encoded_query/1,
+         parse_binary_pct_encoded_userinfo/1, parse_binary_port/1,
+         parse_binary_query/1, parse_binary_scheme/1, parse_binary_userinfo/1,
+         parse_fragment/1, parse_host/1, parse_host_ipv4/1, parse_host_ipv6/1,
+         parse_path/1, parse_pct_encoded_fragment/1, parse_pct_encoded_query/1,
+         parse_pct_encoded_userinfo/1, parse_port/1,
+         parse_query/1, parse_scheme/1, parse_userinfo/1,
+	 parse_list/1, parse_binary/1, parse_mixed/1, parse_relative/1,
+         parse_special/1, parse_special2/1, parse_negative/1,
+         recompose_fragment/1, recompose_parse_fragment/1,
+         recompose_query/1, recompose_parse_query/1,
+         recompose_path/1, recompose_parse_path/1,
+         recompose_autogen/1, parse_recompose_autogen/1,
+         transcode_basic/1, transcode_options/1, transcode_mixed/1, transcode_negative/1
+        ]).
+
+
+-define(SCHEME, "foo").
+-define(USERINFO, "åsa").
+-define(USERINFO_ENC, "%C3%A5sa").
+-define(HOST, "älvsjö").
+-define(HOST_ENC, "%C3%A4lvsj%C3%B6").
+-define(IPV6, "::127.0.0.1").
+-define(IPV6_ENC, "[::127.0.0.1]").
+-define(PORT, 8042).
+-define(PORT_ENC, ":8042").
+-define(PATH, "/där").
+-define(PATH_ENC, "/d%C3%A4r").
+-define(QUERY, "name=örn").
+-define(QUERY_ENC, "?name=%C3%B6rn").
+-define(FRAGMENT, "näsa").
+-define(FRAGMENT_ENC, "#n%C3%A4sa").
+
+
+suite() ->
+    [{timetrap,{minutes,1}}].
+
+all() ->
+    [
+     normalize,
+     parse_binary_scheme,
+     parse_binary_userinfo,
+     parse_binary_pct_encoded_userinfo,
+     parse_binary_host,
+     parse_binary_host_ipv4,
+     parse_binary_host_ipv6,
+     parse_binary_port,
+     parse_binary_path,
+     parse_binary_query,
+     parse_binary_pct_encoded_query,
+     parse_binary_fragment,
+     parse_binary_pct_encoded_fragment,
+     parse_scheme,
+     parse_userinfo,
+     parse_pct_encoded_userinfo,
+     parse_host,
+     parse_host_ipv4,
+     parse_host_ipv6,
+     parse_port,
+     parse_path,
+     parse_query,
+     parse_pct_encoded_query,
+     parse_fragment,
+     parse_pct_encoded_fragment,
+     parse_list,
+     parse_binary,
+     parse_mixed,
+     parse_relative,
+     parse_special,
+     parse_special2,
+     parse_negative,
+     recompose_fragment,
+     recompose_parse_fragment,
+     recompose_query,
+     recompose_parse_query,
+     recompose_path,
+     recompose_parse_path,
+     recompose_autogen,
+     parse_recompose_autogen,
+     transcode_basic,
+     transcode_options,
+     transcode_mixed,
+     transcode_negative
+    ].
+
+groups() ->
+    [].
+
+
+%%-------------------------------------------------------------------------
+%% Helper functions
+%%-------------------------------------------------------------------------
+uri_combinations() ->
+    [[Sch,Usr,Hst,Prt,Pat,Qry,Frg] ||
+        Sch <- [fun update_scheme/1, fun update_scheme_binary/1, none],
+        Usr <- [fun update_userinfo/1, fun update_userinfo_binary/1, none],
+        Hst <- [fun update_host/1, fun update_host_binary/1,
+                fun update_ipv6/1, fun update_ipv6_binary/1, none],
+        Prt <- [fun update_port/1, none],
+        Pat <- [fun update_path/1, fun update_path_binary/1],
+        Qry <- [fun update_query/1,fun update_query_binary/1, none],
+        Frg <- [fun update_fragment/1, fun update_fragment_binary/1, none],
+        not (Usr =:= none andalso Hst =:= none andalso Prt =/= none),
+        not (Usr =/= none andalso Hst =:= none andalso Prt =:= none),
+        not (Usr =/= none andalso Hst =:= none andalso Prt =/= none)].
+
+
+generate_test_vector(Comb) ->
+    Fun = fun (F, {Map, URI}) when is_function(F) -> F({Map, URI});
+              (_, Map) -> Map
+          end,
+    lists:foldl(Fun, {#{}, empty}, Comb).
+
+generate_test_vectors(L) ->
+    lists:map(fun generate_test_vector/1, L).
+
+update_fragment({In, empty}) ->
+    {In#{fragment => ?FRAGMENT}, ?FRAGMENT_ENC};
+update_fragment({In, Out}) when is_list(Out) ->
+    {In#{fragment => ?FRAGMENT}, Out ++ ?FRAGMENT_ENC};
+update_fragment({In, Out}) when is_binary(Out) ->
+    {In#{fragment => ?FRAGMENT}, binary_to_list(Out) ++ ?FRAGMENT_ENC}.
+
+update_fragment_binary({In, empty}) ->
+    {In#{fragment => <<?FRAGMENT/utf8>>}, <<?FRAGMENT_ENC>>};
+update_fragment_binary({In, Out}) when is_list(Out) ->
+    {In#{fragment => <<?FRAGMENT/utf8>>}, Out ++ ?FRAGMENT_ENC};
+update_fragment_binary({In, Out}) when is_binary(Out) ->
+    {In#{fragment => <<?FRAGMENT/utf8>>}, <<Out/binary,?FRAGMENT_ENC>>}.
+
+
+update_query({In, empty}) ->
+    {In#{query => ?QUERY}, ?QUERY_ENC};
+update_query({In, Out}) when is_list(Out) ->
+    {In#{query => ?QUERY}, Out ++ ?QUERY_ENC};
+update_query({In, Out}) when is_binary(Out) ->
+    {In#{query => ?QUERY}, binary_to_list(Out) ++ ?QUERY_ENC}.
+
+update_query_binary({In, empty}) ->
+    {In#{query => <<?QUERY/utf8>>}, <<?QUERY_ENC>>};
+update_query_binary({In, Out}) when is_list(Out) ->
+    {In#{query => <<?QUERY/utf8>>}, Out ++ ?QUERY_ENC};
+update_query_binary({In, Out}) when is_binary(Out) ->
+    {In#{query => <<?QUERY/utf8>>}, <<Out/binary,?QUERY_ENC>>}.
+
+update_path({In, empty}) ->
+    {In#{path => ?PATH}, ?PATH_ENC};
+update_path({In, Out}) when is_list(Out) ->
+    {In#{path => ?PATH}, Out ++ ?PATH_ENC};
+update_path({In, Out}) when is_binary(Out) ->
+    {In#{path => ?PATH}, binary_to_list(Out) ++ ?PATH_ENC}.
+
+update_path_binary({In, empty}) ->
+    {In#{path => <<?PATH/utf8>>}, <<?PATH_ENC>>};
+update_path_binary({In, Out}) when is_list(Out) ->
+    {In#{path => <<?PATH/utf8>>}, Out ++ ?PATH_ENC};
+update_path_binary({In, Out}) when is_binary(Out) ->
+    {In#{path => <<?PATH/utf8>>}, <<Out/binary,?PATH_ENC>>}.
+
+update_port({In, Out}) when is_list(Out) ->
+    {In#{port => ?PORT}, Out ++ ?PORT_ENC};
+update_port({In, Out}) when is_binary(Out) ->
+    {In#{port => ?PORT}, <<Out/binary,?PORT_ENC>>}.
+
+update_host({In, empty}) ->
+    {In#{host => ?HOST}, "//" ++ ?HOST_ENC};
+update_host({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?HOST}, Out ++ [$@|?HOST_ENC]};
+        false -> {In#{host => ?HOST}, Out ++ [$/,$/|?HOST_ENC]}
+    end;
+update_host({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?HOST}, binary_to_list(Out) ++ [$@|?HOST_ENC]};
+        false -> {In#{host => ?HOST}, binary_to_list(Out) ++ [$/,$/|?HOST_ENC]}
+    end.
+
+update_host_binary({In, empty}) ->
+    {In#{host => <<?HOST/utf8>>}, <<"//",?HOST_ENC>>};
+update_host_binary({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?HOST/utf8>>}, Out ++ [$@|?HOST_ENC]};
+        false -> {In#{host => <<?HOST/utf8>>}, Out ++ [$/,$/|?HOST_ENC]}
+    end;
+update_host_binary({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?HOST/utf8>>}, <<Out/binary,$@,?HOST_ENC>>};
+        false-> {In#{host => <<?HOST/utf8>>}, <<Out/binary,"//",?HOST_ENC>>}
+    end.
+
+update_ipv6({In, empty}) ->
+    {In#{host => ?IPV6}, "//" ++ ?IPV6_ENC};
+update_ipv6({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?IPV6}, Out ++ [$@|?IPV6_ENC]};
+        false -> {In#{host => ?IPV6}, Out ++ [$/,$/|?IPV6_ENC]}
+    end;
+update_ipv6({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => ?IPV6}, binary_to_list(Out) ++ [$@|?IPV6_ENC]};
+        false -> {In#{host => ?IPV6}, binary_to_list(Out) ++ [$/,$/|?IPV6_ENC]}
+    end.
+
+update_ipv6_binary({In, empty}) ->
+    {In#{host => <<?IPV6/utf8>>}, <<"//",?IPV6_ENC>>};
+update_ipv6_binary({In, Out}) when is_list(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?IPV6/utf8>>}, Out ++ [$@|?IPV6_ENC]};
+        false -> {In#{host => <<?IPV6/utf8>>}, Out ++ [$/,$/|?IPV6_ENC]}
+    end;
+update_ipv6_binary({In, Out}) when is_binary(Out) ->
+    case maps:is_key(userinfo, In) of
+        true -> {In#{host => <<?IPV6/utf8>>}, <<Out/binary,$@,?IPV6_ENC>>};
+        false-> {In#{host => <<?IPV6/utf8>>}, <<Out/binary,"//",?IPV6_ENC>>}
+    end.
+
+update_userinfo({In, empty}) ->
+    {In#{userinfo => ?USERINFO}, "//" ++ ?USERINFO_ENC};
+update_userinfo({In, Out}) when is_list(Out) ->
+    {In#{userinfo => ?USERINFO}, Out ++ "//" ++ ?USERINFO_ENC};
+update_userinfo({In, Out}) when is_binary(Out) ->
+    {In#{userinfo => ?USERINFO}, binary_to_list(Out) ++ "//" ++ ?USERINFO_ENC}.
+
+update_userinfo_binary({In, empty}) ->
+    {In#{userinfo => <<?USERINFO/utf8>>}, <<"//",?USERINFO_ENC>>};
+update_userinfo_binary({In, Out}) when is_list(Out) ->
+    {In#{userinfo => <<?USERINFO/utf8>>}, Out ++ "//" ++ ?USERINFO_ENC};
+update_userinfo_binary({In, Out}) when is_binary(Out) ->
+    {In#{userinfo => <<?USERINFO/utf8>>}, <<Out/binary,"//",?USERINFO_ENC>>}.
+
+update_scheme({In, empty}) ->
+    {In#{scheme => ?SCHEME}, ?SCHEME ++ ":"}.
+
+update_scheme_binary({In, empty}) ->
+    {In#{scheme => <<?SCHEME/utf8>>}, <<?SCHEME,$:>>}.
+
+
+%% Test recompose on a generated test vector
+run_test_recompose({#{}, empty}) ->
+    try "" = uri_string:recompose(#{}) of
+        _ -> ok
+    catch
+        _:_ -> error({test_failed, #{}, ""})
+    end;
+run_test_recompose({Map, URI}) ->
+    try URI = uri_string:recompose(Map) of
+        URI -> ok
+    catch
+        _:_ -> error({test_failed, Map, URI})
+    end.
+
+%% Test parse - recompose on a generated test vector
+run_test_parse_recompose({#{}, empty}) ->
+    try "" = uri_string:recompose(uri_string:parse("")) of
+        _ -> ok
+    catch
+        _:_ -> error({test_failed, #{}, ""})
+    end;
+run_test_parse_recompose({Map, URI}) ->
+    try URI = uri_string:recompose(uri_string:parse(URI)) of
+        URI -> ok
+    catch
+        _:_ -> error({test_failed, Map, URI})
+    end.
+
+
+%%-------------------------------------------------------------------------
+%% Parse tests
+%%-------------------------------------------------------------------------
+
+parse_binary_scheme(_Config) ->
+    #{} = uri_string:parse(<<>>),
+    #{path := <<"foo">>} = uri_string:parse(<<"foo">>),
+    #{scheme := <<"foo">>} = uri_string:parse(<<"foo:">>),
+    #{scheme := <<"foo">>, path := <<"bar:nisse">>} = uri_string:parse(<<"foo:bar:nisse">>),
+    #{scheme := <<"foo">>, host := <<"">>} = uri_string:parse(<<"foo://">>),
+    #{scheme := <<"foo">>, host := <<"">>, path := <<"/">>} = uri_string:parse(<<"foo:///">>),
+    #{scheme := <<"foo">>, host := <<"">>, path := <<"//">>} = uri_string:parse(<<"foo:////">>),
+
+    #{path := <<"/">>} = uri_string:parse(<<"/">>),
+    #{host := <<>>} = uri_string:parse(<<"//">>),
+    #{host := <<>>, path := <<"/">>} = uri_string:parse(<<"///">>).
+
+parse_binary_userinfo(_Config) ->
+    #{scheme := <<"user">>, path := <<"password@localhost">>} =
+        uri_string:parse(<<"user:password@localhost">>),
+    #{path := <<"user@">>} = uri_string:parse(<<"user@">>),
+    #{path := <<"/user@">>} = uri_string:parse(<<"/user@">>),
+    #{path := <<"user@localhost">>} = uri_string:parse(<<"user@localhost">>),
+    #{userinfo := <<"user">>, host := <<"localhost">>} = uri_string:parse(<<"//user@localhost">>),
+    #{userinfo := <<"user:password">>, host := <<"localhost">>} =
+        uri_string:parse(<<"//user:password@localhost">>),
+    #{scheme := <<"foo">>, path := <<"/user@">>} =
+        uri_string:parse(<<"foo:/user@">>),
+    #{scheme := <<"foo">>, userinfo := <<"user">>, host := <<"localhost">>} =
+        uri_string:parse(<<"foo://user@localhost">>),
+    #{scheme := <<"foo">>, userinfo := <<"user:password">>, host := <<"localhost">>} =
+        uri_string:parse(<<"foo://user:password@localhost">>).
+
+parse_binary_pct_encoded_userinfo(_Config) ->
+    #{scheme := <<"user">>, path := <<"合@気道"/utf8>>} =
+        uri_string:parse(<<"user:%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{path := <<"合気道@"/utf8>>} = uri_string:parse(<<"%E5%90%88%E6%B0%97%E9%81%93@">>),
+    #{path := <<"/合気道@"/utf8>>} = uri_string:parse(<<"/%E5%90%88%E6%B0%97%E9%81%93@">>),
+    #{path := <<"合@気道"/utf8>>} = uri_string:parse(<<"%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{userinfo := <<"合"/utf8>>, host := <<"気道"/utf8>>} =
+        uri_string:parse(<<"//%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{userinfo := <<"合:気"/utf8>>, host := <<"道"/utf8>>} =
+        uri_string:parse(<<"//%E5%90%88:%E6%B0%97@%E9%81%93">>),
+    #{scheme := <<"foo">>, path := <<"/合気道@"/utf8>>} =
+        uri_string:parse(<<"foo:/%E5%90%88%E6%B0%97%E9%81%93@">>),
+    #{scheme := <<"foo">>, userinfo := <<"合"/utf8>>, host := <<"気道"/utf8>>} =
+        uri_string:parse(<<"foo://%E5%90%88@%E6%B0%97%E9%81%93">>),
+    #{scheme := <<"foo">>, userinfo := <<"合:気"/utf8>>, host := <<"道"/utf8>>} =
+        uri_string:parse(<<"foo://%E5%90%88:%E6%B0%97@%E9%81%93">>),
+    {error,invalid_uri,"@"} = uri_string:parse(<<"//%E5%90%88@%E6%B0%97%E9%81%93@">>),
+    {error,invalid_uri,":"} = uri_string:parse(<<"foo://%E5%90%88@%E6%B0%97%E9%81%93@">>).
+
+parse_binary_host(_Config) ->
+    #{host := <<"hostname">>} = uri_string:parse(<<"//hostname">>),
+    #{host := <<"hostname">>,scheme := <<"foo">>} = uri_string:parse(<<"foo://hostname">>),
+    #{host := <<"hostname">>,scheme := <<"foo">>, userinfo := <<"user">>} =
+        uri_string:parse(<<"foo://user@hostname">>).
+
+parse_binary_host_ipv4(_Config) ->
+    #{host := <<"127.0.0.1">>} = uri_string:parse(<<"//127.0.0.1">>),
+    #{host := <<"127.0.0.1">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"//127.0.0.1/over/there">>),
+    #{host := <<"127.0.0.1">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//127.0.0.1?name=ferret">>),
+    #{host := <<"127.0.0.1">>, fragment := <<"nose">>} = uri_string:parse(<<"//127.0.0.1#nose">>),
+    {error,invalid_uri,"x"} = uri_string:parse(<<"//127.0.0.x">>),
+    {error,invalid_uri,"1227.0.0.1"} = uri_string:parse(<<"//1227.0.0.1">>).
+
+parse_binary_host_ipv6(_Config) ->
+    #{host := <<"::127.0.0.1">>} = uri_string:parse(<<"//[::127.0.0.1]">>),
+    #{host := <<"2001:0db8:0000:0000:0000:0000:1428:07ab">>} =
+        uri_string:parse(<<"//[2001:0db8:0000:0000:0000:0000:1428:07ab]">>),
+    #{host := <<"::127.0.0.1">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"//[::127.0.0.1]/over/there">>),
+    #{host := <<"::127.0.0.1">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//[::127.0.0.1]?name=ferret">>),
+    #{host := <<"::127.0.0.1">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"//[::127.0.0.1]#nose">>),
+    {error,invalid_uri,"x"} = uri_string:parse(<<"//[::127.0.0.x]">>),
+    {error,invalid_uri,"::1227.0.0.1"} = uri_string:parse(<<"//[::1227.0.0.1]">>),
+    {error,invalid_uri,"G"} = uri_string:parse(<<"//[2001:0db8:0000:0000:0000:0000:1428:G7ab]">>).
+
+parse_binary_port(_Config) ->
+    #{path:= <<"/:8042">>} =
+        uri_string:parse(<<"/:8042">>),
+    #{host:= <<>>, port := 8042} =
+        uri_string:parse(<<"//:8042">>),
+    #{host := <<"example.com">>, port:= 8042} =
+        uri_string:parse(<<"//example.com:8042">>),
+    #{scheme := <<"foo">>, path := <<"/:8042">>} =
+        uri_string:parse(<<"foo:/:8042">>),
+    #{scheme := <<"foo">>, host := <<>>, port := 8042} =
+        uri_string:parse(<<"foo://:8042">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, port := 8042} =
+        uri_string:parse(<<"foo://example.com:8042">>),
+    {error,invalid_uri,":"} = uri_string:parse(":600"),
+    {error,invalid_uri,"x"} = uri_string:parse("//:8042x").
+
+parse_binary_path(_Config) ->
+    #{path := <<"over/there">>} = uri_string:parse(<<"over/there">>),
+    #{path := <<"/over/there">>} = uri_string:parse(<<"/over/there">>),
+    #{scheme := <<"foo">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"foo:/over/there">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/over/there">>} =
+        uri_string:parse(<<"foo://example.com/over/there">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/over/there">>, port := 8042} =
+        uri_string:parse(<<"foo://example.com:8042/over/there">>).
+
+parse_binary_query(_Config) ->
+    #{scheme := <<"foo">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo:?name=ferret">>),
+    #{scheme := <<"foo">>, path:= <<"over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo:over/there?name=ferret">>),
+    #{scheme := <<"foo">>, path:= <<"/over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo:/over/there?name=ferret">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo://example.com?name=ferret">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"foo://example.com/?name=ferret">>),
+
+    #{path := <<>>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"?name=ferret">>),
+    #{path := <<"over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"over/there?name=ferret">>),
+    #{path := <<"/">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"/?name=ferret">>),
+    #{path := <<"/over/there">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"/over/there?name=ferret">>),
+    #{host := <<"example.com">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//example.com?name=ferret">>),
+    #{host := <<"example.com">>, path := <<"/">>, query := <<"name=ferret">>} =
+        uri_string:parse(<<"//example.com/?name=ferret">>).
+
+parse_binary_pct_encoded_query(_Config) ->
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/">>,
+      query := <<"name=合気道"/utf8>>} =
+        uri_string:parse(<<"foo://example.com/?name=%E5%90%88%E6%B0%97%E9%81%93">>),
+    #{host := <<"example.com">>, path := <<"/">>, query := <<"name=合気道"/utf8>>} =
+        uri_string:parse(<<"//example.com/?name=%E5%90%88%E6%B0%97%E9%81%93">>).
+
+parse_binary_fragment(_Config) ->
+    #{scheme := <<"foo">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo:#nose">>),
+    #{scheme := <<"foo">>, path:= <<"over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo:over/there#nose">>),
+    #{scheme := <<"foo">>, path:= <<"/over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo:/over/there#nose">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com#nose">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, path := <<"/">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com/#nose">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com#nose">>),
+
+    #{fragment := <<"nose">>} =
+        uri_string:parse(<<"#nose">>),
+    #{path := <<"over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"over/there#nose">>),
+    #{path := <<"/">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"/#nose">>),
+    #{path := <<"/over/there">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"/over/there#nose">>),
+    #{host := <<"example.com">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"//example.com#nose">>),
+    #{host := <<"example.com">>, path := <<"/">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"//example.com/#nose">>).
+
+parse_binary_pct_encoded_fragment(_Config) ->
+    #{scheme := <<"foo">>, host := <<"example.com">>, fragment := <<"合気道"/utf8>>} =
+        uri_string:parse(<<"foo://example.com#%E5%90%88%E6%B0%97%E9%81%93">>),
+    #{host := <<"example.com">>, path := <<"/">>, fragment := <<"合気道"/utf8>>} =
+        uri_string:parse(<<"//example.com/#%E5%90%88%E6%B0%97%E9%81%93">>).
+
+parse_scheme(_Config) ->
+    #{} = uri_string:parse(""),
+    #{path := "foo"} = uri_string:parse("foo"),
+    #{scheme := "foo"} = uri_string:parse("foo:"),
+    #{scheme := "foo", path := "bar:nisse"} = uri_string:parse("foo:bar:nisse"),
+    #{scheme := "foo", host := ""} = uri_string:parse("foo://"),
+    #{scheme := "foo", host := "", path := "/"} = uri_string:parse("foo:///"),
+    #{scheme := "foo", host := "", path := "//"} = uri_string:parse("foo:////"),
+
+    #{path := "/"} = uri_string:parse("/"),
+    #{host := ""} = uri_string:parse("//"),
+    #{host := "", path := "/"} = uri_string:parse("///").
+
+parse_userinfo(_Config) ->
+    #{scheme := "user", path := "password@localhost"} = uri_string:parse("user:password@localhost"),
+    #{path := "user@"} = uri_string:parse("user@"),
+    #{path := "/user@"} = uri_string:parse("/user@"),
+    #{path := "user@localhost"} = uri_string:parse("user@localhost"),
+    #{userinfo := "user", host := "localhost"} = uri_string:parse("//user@localhost"),
+    #{userinfo := "user:password", host := "localhost"} =
+        uri_string:parse("//user:password@localhost"),
+    #{scheme := "foo", path := "/user@"} =
+        uri_string:parse("foo:/user@"),
+    #{scheme := "foo", userinfo := "user", host := "localhost"} =
+        uri_string:parse("foo://user@localhost"),
+    #{scheme := "foo", userinfo := "user:password", host := "localhost"} =
+        uri_string:parse("foo://user:password@localhost").
+
+parse_pct_encoded_userinfo(_Config) ->
+    #{scheme := "user", path := "合@気道"} =
+        uri_string:parse("user:%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{path := "合気道@"} = uri_string:parse("%E5%90%88%E6%B0%97%E9%81%93@"),
+    #{path := "/合気道@"} = uri_string:parse("/%E5%90%88%E6%B0%97%E9%81%93@"),
+    #{path := "合@気道"} = uri_string:parse("%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{userinfo := "合", host := "気道"} =
+        uri_string:parse("//%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{userinfo := "合:気", host := "道"} =
+        uri_string:parse("//%E5%90%88:%E6%B0%97@%E9%81%93"),
+    #{scheme := "foo", path := "/合気道@"} =
+        uri_string:parse("foo:/%E5%90%88%E6%B0%97%E9%81%93@"),
+    #{scheme := "foo", userinfo := "合", host := "気道"} =
+        uri_string:parse("foo://%E5%90%88@%E6%B0%97%E9%81%93"),
+    #{scheme := "foo", userinfo := "合:気", host := "道"} =
+        uri_string:parse("foo://%E5%90%88:%E6%B0%97@%E9%81%93"),
+    {error,invalid_uri,"@"} = uri_string:parse("//%E5%90%88@%E6%B0%97%E9%81%93@"),
+    {error,invalid_uri,":"} = uri_string:parse("foo://%E5%90%88@%E6%B0%97%E9%81%93@").
+
+
+parse_host(_Config) ->
+    #{host := "hostname"} = uri_string:parse("//hostname"),
+    #{host := "hostname",scheme := "foo"} = uri_string:parse("foo://hostname"),
+    #{host := "hostname",scheme := "foo", userinfo := "user"} =
+        uri_string:parse("foo://user@hostname").
+
+parse_host_ipv4(_Config) ->
+    #{host := "127.0.0.1"} = uri_string:parse("//127.0.0.1"),
+    #{host := "2001:0db8:0000:0000:0000:0000:1428:07ab"} =
+        uri_string:parse("//[2001:0db8:0000:0000:0000:0000:1428:07ab]"),
+    #{host := "127.0.0.1", path := "/over/there"} = uri_string:parse("//127.0.0.1/over/there"),
+    #{host := "127.0.0.1", query := "name=ferret"} = uri_string:parse("//127.0.0.1?name=ferret"),
+    #{host := "127.0.0.1", fragment := "nose"} = uri_string:parse("//127.0.0.1#nose"),
+    {error,invalid_uri,"x"} = uri_string:parse("//127.0.0.x"),
+    {error,invalid_uri,"1227.0.0.1"} = uri_string:parse("//1227.0.0.1").
+
+parse_host_ipv6(_Config) ->
+    #{host := "::127.0.0.1"} = uri_string:parse("//[::127.0.0.1]"),
+    #{host := "::127.0.0.1", path := "/over/there"} = uri_string:parse("//[::127.0.0.1]/over/there"),
+    #{host := "::127.0.0.1", query := "name=ferret"} =
+        uri_string:parse("//[::127.0.0.1]?name=ferret"),
+    #{host := "::127.0.0.1", fragment := "nose"} = uri_string:parse("//[::127.0.0.1]#nose"),
+    {error,invalid_uri,"x"} = uri_string:parse("//[::127.0.0.x]"),
+    {error,invalid_uri,"::1227.0.0.1"} = uri_string:parse("//[::1227.0.0.1]"),
+    {error,invalid_uri,"G"} = uri_string:parse("//[2001:0db8:0000:0000:0000:0000:1428:G7ab]").
+
+parse_port(_Config) ->
+    #{path:= "/:8042"} =
+        uri_string:parse("/:8042"),
+    #{host:= "", port := 8042} =
+        uri_string:parse("//:8042"),
+    #{host := "example.com", port:= 8042} =
+        uri_string:parse("//example.com:8042"),
+    #{scheme := "foo", path := "/:8042"} =
+        uri_string:parse("foo:/:8042"),
+    #{scheme := "foo", host := "", port := 8042} =
+        uri_string:parse("foo://:8042"),
+    #{scheme := "foo", host := "example.com", port := 8042} =
+        uri_string:parse("foo://example.com:8042").
+
+parse_path(_Config) ->
+    #{path := "over/there"} = uri_string:parse("over/there"),
+    #{path := "/over/there"} = uri_string:parse("/over/there"),
+    #{scheme := "foo", path := "/over/there"} =
+        uri_string:parse("foo:/over/there"),
+    #{scheme := "foo", host := "example.com", path := "/over/there"} =
+        uri_string:parse("foo://example.com/over/there"),
+    #{scheme := "foo", host := "example.com", path := "/over/there", port := 8042} =
+        uri_string:parse("foo://example.com:8042/over/there").
+
+parse_query(_Config) ->
+    #{scheme := "foo", query := "name=ferret"} =
+        uri_string:parse("foo:?name=ferret"),
+    #{scheme := "foo", path:= "over/there", query := "name=ferret"} =
+        uri_string:parse("foo:over/there?name=ferret"),
+    #{scheme := "foo", path:= "/over/there", query := "name=ferret"} =
+        uri_string:parse("foo:/over/there?name=ferret"),
+    #{scheme := "foo", host := "example.com", query := "name=ferret"} =
+        uri_string:parse("foo://example.com?name=ferret"),
+    #{scheme := "foo", host := "example.com", path := "/", query := "name=ferret"} =
+        uri_string:parse("foo://example.com/?name=ferret"),
+
+    #{path := "", query := "name=ferret"} =
+        uri_string:parse("?name=ferret"),
+    #{path := "over/there", query := "name=ferret"} =
+        uri_string:parse("over/there?name=ferret"),
+    #{path := "/", query := "name=ferret"} =
+        uri_string:parse("/?name=ferret"),
+    #{path := "/over/there", query := "name=ferret"} =
+        uri_string:parse("/over/there?name=ferret"),
+    #{host := "example.com", query := "name=ferret"} =
+        uri_string:parse("//example.com?name=ferret"),
+    #{host := "example.com", path := "/", query := "name=ferret"} =
+        uri_string:parse("//example.com/?name=ferret").
+
+parse_pct_encoded_query(_Config) ->
+    #{scheme := "foo", host := "example.com", path := "/",
+      query := "name=合気道"} =
+        uri_string:parse("foo://example.com/?name=%E5%90%88%E6%B0%97%E9%81%93"),
+    #{host := "example.com", path := "/", query := "name=合気道"} =
+        uri_string:parse("//example.com/?name=%E5%90%88%E6%B0%97%E9%81%93").
+
+parse_fragment(_Config) ->
+    #{scheme := "foo", fragment := "nose"} =
+        uri_string:parse("foo:#nose"),
+    #{scheme := "foo", path:= "over/there", fragment := "nose"} =
+        uri_string:parse("foo:over/there#nose"),
+    #{scheme := "foo", path:= "/over/there", fragment := "nose"} =
+        uri_string:parse("foo:/over/there#nose"),
+    #{scheme := "foo", host := "example.com", fragment := "nose"} =
+        uri_string:parse("foo://example.com#nose"),
+    #{scheme := "foo", host := "example.com", path := "/", fragment := "nose"} =
+        uri_string:parse("foo://example.com/#nose"),
+    #{scheme := "foo", host := "example.com", fragment := "nose"} =
+        uri_string:parse("foo://example.com#nose"),
+
+    #{fragment := "nose"} =
+        uri_string:parse("#nose"),
+    #{path := "over/there", fragment := "nose"} =
+        uri_string:parse("over/there#nose"),
+    #{path := "/", fragment := "nose"} =
+        uri_string:parse("/#nose"),
+    #{path := "/over/there", fragment := "nose"} =
+        uri_string:parse("/over/there#nose"),
+    #{host := "example.com", fragment := "nose"} =
+        uri_string:parse("//example.com#nose"),
+    #{host := "example.com", path := "/", fragment := "nose"} =
+        uri_string:parse("//example.com/#nose").
+
+parse_pct_encoded_fragment(_Config) ->
+    #{scheme := "foo", host := "example.com", fragment := "合気道"} =
+        uri_string:parse("foo://example.com#%E5%90%88%E6%B0%97%E9%81%93"),
+    #{host := "example.com", path := "/", fragment := "合気道"} =
+        uri_string:parse("//example.com/#%E5%90%88%E6%B0%97%E9%81%93").
+
+parse_list(_Config) ->
+    #{scheme := "foo", path := "bar:nisse"} = uri_string:parse("foo:bar:nisse"),
+    #{scheme := "foo", host := "example.com", port := 8042,
+      path := "/over/there", query := "name=ferret", fragment := "nose"} =
+        uri_string:parse("foo://example.com:8042/over/there?name=ferret#nose"),
+    #{scheme := "foo", userinfo := "admin:admin", host := "example.com", port := 8042,
+      path := "/over/there", query := "name=ferret", fragment := "nose"} =
+        uri_string:parse("foo://admin:[email protected]:8042/over/there?name=ferret#nose").
+
+parse_binary(_Config) ->
+    #{scheme := <<"foo">>, path := <<"bar:nisse">>} = uri_string:parse(<<"foo:bar:nisse">>),
+    #{scheme := <<"foo">>, host := <<"example.com">>, port := 8042,
+      path := <<"/over/there">>, query := <<"name=ferret">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://example.com:8042/over/there?name=ferret#nose">>),
+    #{scheme := <<"foo">>, userinfo := <<"admin:admin">>, host := <<"example.com">>, port := 8042,
+      path := <<"/over/there">>, query := <<"name=ferret">>, fragment := <<"nose">>} =
+        uri_string:parse(<<"foo://admin:[email protected]:8042/over/there?name=ferret#nose">>).
+
+
+parse_mixed(_Config) ->
+    #{scheme := "foo", path := "bar"} =
+        uri_string:parse(lists:append("fo",<<"o:bar">>)),
+    #{scheme := "foo", path := "bar"} =
+        uri_string:parse(lists:append("foo:b",<<"ar">>)),
+    #{scheme := "foo", path := "bar:bar"} =
+        uri_string:parse([[102],[111,111],<<":bar">>,58,98,97,114]).
+
+parse_relative(_Config) ->
+    #{path := "/path"} =
+        uri_string:parse(lists:append("/pa",<<"th">>)),
+    #{path := "foo"} =
+        uri_string:parse(lists:append("fo",<<"o">>)).
+
+parse_special(_Config) ->
+    #{host := [],query := []} = uri_string:parse("//?"),
+    #{fragment := [],host := []} = uri_string:parse("//#"),
+    #{host := [],query := [],scheme := "foo"} = uri_string:parse("foo://?"),
+    #{fragment := [],host := [],scheme := "foo"} = uri_string:parse("foo://#"),
+    #{host := <<>>, path := <<"/">>} = uri_string:parse(<<"///">>),
+    #{host := <<"hostname">>} = uri_string:parse(<<"//hostname">>),
+    #{host := <<>>, path := <<"/hostname">>} = uri_string:parse(<<"///hostname">>),
+    #{host :=  [],path := "/",query := []} = uri_string:parse("///?"),
+    #{fragment := [],host := [],path := "/"} = uri_string:parse("///#"),
+    #{host := "foo",query := []} = uri_string:parse("//foo?"),
+    #{fragment := [],host := "foo"} = uri_string:parse("//foo#"),
+    #{host := "foo",path := "/"} = uri_string:parse("//foo/"),
+    #{host := "foo",query := [],scheme := "http"} = uri_string:parse("http://foo?"),
+    #{fragment := [],host := "foo",scheme := "http"} = uri_string:parse("http://foo#"),
+    #{host := "foo",path := "/",scheme := "http"} = uri_string:parse("http://foo/"),
+    #{fragment := [],host := "host",port := 80,scheme := "http"} = uri_string:parse("http://host:80#"),
+    #{host := "host",port := 80,query := [],scheme := "http"} = uri_string:parse("http://host:80?"),
+    #{path := [],query := []} = uri_string:parse("?"),
+    #{path := [],query := "?"} = uri_string:parse("??"),
+    #{path := [],query := "??"} = uri_string:parse("???").
+
+parse_special2(_Config) ->
+    #{host := [],path := "/",port := 1,scheme := "a"} = uri_string:parse("a://:1/"),
+    #{path := "/a/",scheme := "a"} = uri_string:parse("a:/a/"),
+    #{host := [],path := [],userinfo := []} = uri_string:parse("//@"),
+    #{host := [],path := [],scheme := "foo",userinfo := []} = uri_string:parse("foo://@"),
+    #{host := [],path := "/",userinfo := []} = uri_string:parse("//@/"),
+    #{host := [],path := "/",scheme := "foo",userinfo := []} = uri_string:parse("foo://@/"),
+    #{host := "localhost",path := "/",port := undefined} = uri_string:parse("//localhost:/"),
+    #{host := [],path := [],port := undefined} = uri_string:parse("//:").
+
+parse_negative(_Config) ->
+    {error,invalid_uri,"å"} = uri_string:parse("å"),
+    {error,invalid_uri,"å"} = uri_string:parse("aå:/foo"),
+    {error,invalid_uri,":"} = uri_string:parse("foo://usär@host"),
+    {error,invalid_uri,"ö"} = uri_string:parse("//host/path?foö=bar"),
+    {error,invalid_uri,"ö"} = uri_string:parse("//host/path#foö"),
+    {error,invalid_uri,"127.256.0.1"} = uri_string:parse("//127.256.0.1"),
+    {error,invalid_uri,":::127.0.0.1"} = uri_string:parse("//[:::127.0.0.1]"),
+    {error,invalid_utf8,<<0,0,0,246>>} = uri_string:parse("//%00%00%00%F6"),
+    {error,invalid_uri,"A"} = uri_string:parse("//localhost:A8").
+
+
+%%-------------------------------------------------------------------------
+%% Recompose tests
+%%-------------------------------------------------------------------------
+recompose_fragment(_Config) ->
+    <<?FRAGMENT_ENC>> = uri_string:recompose(#{fragment => <<?FRAGMENT/utf8>>, path => <<>>}),
+    ?FRAGMENT_ENC = uri_string:recompose(#{fragment => ?FRAGMENT, path => ""}).
+
+recompose_parse_fragment(_Config) ->
+    <<?FRAGMENT_ENC>> = uri_string:recompose(uri_string:parse(<<?FRAGMENT_ENC>>)),
+    ?FRAGMENT_ENC = uri_string:recompose(uri_string:parse(?FRAGMENT_ENC)).
+
+recompose_query(_Config) ->
+    <<?QUERY_ENC>> =
+        uri_string:recompose(#{query => <<?QUERY/utf8>>, path => <<>>}),
+    <<?QUERY_ENC?FRAGMENT_ENC>> =
+        uri_string:recompose(#{query => <<?QUERY/utf8>>,
+                               fragment => <<?FRAGMENT/utf8>>,
+                               path => <<>>}),
+    "?name=%C3%B6rn" =
+        uri_string:recompose(#{query => "name=örn", path => ""}),
+    "?name=%C3%B6rn#n%C3%A4sa" =
+        uri_string:recompose(#{query => "name=örn",
+                               fragment => "näsa",
+                               path => ""}).
+
+recompose_parse_query(_Config) ->
+    <<"?name=%C3%B6rn">> = uri_string:recompose(uri_string:parse(<<"?name=%C3%B6rn">>)),
+    <<"?name=%C3%B6rn#n%C3%A4sa">> =
+        uri_string:recompose(uri_string:parse(<<"?name=%C3%B6rn#n%C3%A4sa">>)),
+    "?name=%C3%B6rn" = uri_string:recompose(uri_string:parse("?name=%C3%B6rn")),
+    "?name=%C3%B6rn#n%C3%A4sa" = uri_string:recompose(uri_string:parse("?name=%C3%B6rn#n%C3%A4sa")).
+
+recompose_path(_Config) ->
+    <<"/d%C3%A4r">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>}),
+    <<"/d%C3%A4r#n%C3%A4sa">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>,
+                               fragment => <<"näsa"/utf8>>}),
+    <<"/d%C3%A4r?name=%C3%B6rn">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>,
+                               query => <<"name=örn"/utf8>>}),
+    <<"/d%C3%A4r?name=%C3%B6rn#n%C3%A4sa">> =
+        uri_string:recompose(#{path => <<"/där"/utf8>>,
+                               query => <<"name=örn"/utf8>>,
+                               fragment => <<"näsa"/utf8>>}),
+
+
+    "/d%C3%A4r" =
+        uri_string:recompose(#{path => "/där"}),
+    "/d%C3%A4r#n%C3%A4sa" =
+        uri_string:recompose(#{path => "/där",
+                               fragment => "näsa"}),
+    "/d%C3%A4r?name=%C3%B6rn" =
+        uri_string:recompose(#{path => "/där",
+                               query => "name=örn"}),
+    "/d%C3%A4r?name=%C3%B6rn#n%C3%A4sa" =
+        uri_string:recompose(#{path => "/där",
+                               query => "name=örn",
+                               fragment => "näsa"}).
+
+
+recompose_parse_path(_Config) ->
+    <<"/d%C3%A4r">> =
+        uri_string:recompose(uri_string:parse(<<"/d%C3%A4r">>)),
+    <<"/d%C3%A4r#n%C3%A4sa">> =
+        uri_string:recompose(uri_string:parse(<<"/d%C3%A4r#n%C3%A4sa">>)),
+    <<"/d%C3%A4r?name=%C3%B6rn">> =
+        uri_string:recompose(uri_string:parse(<<"/d%C3%A4r?name=%C3%B6rn">>)),
+
+    "/d%C3%A4r" =
+        uri_string:recompose(uri_string:parse("/d%C3%A4r")),
+    "/d%C3%A4r#n%C3%A4sa" =
+        uri_string:recompose(uri_string:parse("/d%C3%A4r#n%C3%A4sa")),
+    "/d%C3%A4r?name=%C3%B6rn" =
+        uri_string:recompose(uri_string:parse("/d%C3%A4r?name=%C3%B6rn")).
+
+
+recompose_autogen(_Config) ->
+    Tests = generate_test_vectors(uri_combinations()),
+    lists:map(fun run_test_recompose/1, Tests).
+
+parse_recompose_autogen(_Config) ->
+    Tests = generate_test_vectors(uri_combinations()),
+    lists:map(fun run_test_parse_recompose/1, Tests).
+
+transcode_basic(_Config) ->
+    <<"foo%C3%B6bar"/utf8>> =
+        uri_string:transcode(<<"foo%00%00%00%F6bar"/utf32>>, [{in_encoding, utf32},{out_encoding, utf8}]),
+    "foo%C3%B6bar" =
+        uri_string:transcode("foo%00%00%00%F6bar", [{in_encoding, utf32},{out_encoding, utf8}]),
+    <<"foo%00%00%00%F6bar"/utf32>> =
+        uri_string:transcode(<<"foo%C3%B6bar"/utf8>>, [{in_encoding, utf8},{out_encoding, utf32}]),
+    "foo%00%00%00%F6bar" =
+        uri_string:transcode("foo%C3%B6bar", [{in_encoding, utf8},{out_encoding, utf32}]),
+    "foo%C3%B6bar" =
+        uri_string:transcode("foo%F6bar", [{in_encoding, latin1},{out_encoding, utf8}]).
+
+transcode_options(_Config) ->
+    <<"foo%C3%B6bar"/utf8>> =
+        uri_string:transcode(<<"foo%C3%B6bar"/utf8>>, []),
+    <<"foo%C3%B6bar"/utf8>> =
+        uri_string:transcode(<<"foo%00%00%00%F6bar"/utf32>>, [{in_encoding, utf32}]),
+    <<"foo%00%00%00%F6bar"/utf32>> =
+        uri_string:transcode(<<"foo%C3%B6bar"/utf8>>, [{out_encoding, utf32}]).
+
+transcode_mixed(_Config) ->
+    "foo%00%00%00%F6bar" =
+        uri_string:transcode(["foo",<<"%C3%B6"/utf8>>,<<"ba"/utf8>>,"r"], [{out_encoding, utf32}]),
+    "foo%00%00%00%F6bar" =
+        uri_string:transcode(["foo",<<"%C3%"/utf8>>,<<"B6ba"/utf8>>,"r"], [{out_encoding, utf32}]),
+    "foo%C3%B6bar" =
+        uri_string:transcode(["foo%00", <<"%00%0"/utf32>>,<<"0%F"/utf32>>,"6bar"], [{in_encoding, utf32},{out_encoding, utf8}]).
+
+transcode_negative(_Config) ->
+    {error,invalid_percent_encoding,"%BXbar"} =
+        uri_string:transcode(<<"foo%C3%BXbar"/utf8>>, [{in_encoding, utf8},{out_encoding, utf32}]),
+    {error,invalid_input,<<"ö">>} =
+        uri_string:transcode("foo%F6bar", [{in_encoding, utf8},{out_encoding, utf8}]).
+
+normalize(_Config) ->
+    "/a/g" = uri_string:normalize("/a/b/c/./../../g"),
+    <<"mid/6">> = uri_string:normalize(<<"mid/content=5/../6">>),
+    "http://localhost-%C3%B6rebro/a/g" =
+        uri_string:normalize("http://localhos%74-%c3%b6rebro:80/a/b/c/./../../g"),
+    <<"http://localhost-%C3%B6rebro/a/g">> =
+        uri_string:normalize(<<"http://localhos%74-%c3%b6rebro:80/a/b/c/./../../g">>),
+    <<"https://localhost/">> =
+        uri_string:normalize(<<"https://localhost:443">>),
+    <<"https://localhost:445/">> =
+        uri_string:normalize(<<"https://localhost:445">>),
+    <<"ftp://localhost">> =
+        uri_string:normalize(<<"ftp://localhost:21">>),
+    <<"ssh://localhost">> =
+        uri_string:normalize(<<"ssh://localhost:22">>),
+    <<"sftp://localhost">> =
+        uri_string:normalize(<<"sftp://localhost:22">>),
+    <<"tftp://localhost">> =
+        uri_string:normalize(<<"tftp://localhost:69">>).
diff --git a/lib/stdlib/test/uri_string_property_test_SUITE.erl b/lib/stdlib/test/uri_string_property_test_SUITE.erl
new file mode 100644
index 0000000000..ae2c61c7aa
--- /dev/null
+++ b/lib/stdlib/test/uri_string_property_test_SUITE.erl
@@ -0,0 +1,39 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2008-2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(uri_string_property_test_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+-compile(export_all).
+
+all() -> [recompose].
+
+init_per_suite(Config) ->
+    ct_property_test:init_per_suite(Config).
+
+end_per_suite(Config) ->
+    Config.
+
+%%%========================================================================
+%%% Test suites
+%%%========================================================================
+recompose(Config) ->
+    ct_property_test:quickcheck(
+      uri_string_recompose:prop_recompose(),
+      Config).