stdlib: Add Unicode modifier t to control sequence a

The Unicode translation modifier 't' is added to the io:fread/2,3
control sequence 'a'.

3 files changed, 14 insertions, 8 deletions

diff --git a/lib/stdlib/doc/src/io.xml b/lib/stdlib/doc/src/io.xml
index 74b57457ea..64fcf4379f 100644
--- a/lib/stdlib/doc/src/io.xml
+++ b/lib/stdlib/doc/src/io.xml
@@ -569,8 +569,6 @@ Prompt> <input>&lt;Characters beyond latin1 range not printable in this medium&g
               <item>
                 <p>Similar to <c>s</c>, but the resulting string is
                   converted into an atom.</p>
-                <p>The Unicode translation modifier is not allowed (atoms
-                  cannot contain characters beyond the <c>latin1</c> range).</p>
               </item>
               <tag><c>c</c></tag>
               <item>
diff --git a/lib/stdlib/src/io_lib_fread.erl b/lib/stdlib/src/io_lib_fread.erl
index 6a8f8f728e..983e8d4566 100644
--- a/lib/stdlib/src/io_lib_fread.erl
+++ b/lib/stdlib/src/io_lib_fread.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2017. 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.
@@ -159,8 +159,8 @@ fread_field([$t|Format], F, Sup, _Unic) ->
 fread_field(Format, F, Sup, Unic) ->
     {Format,F,Sup,Unic}.
 
-%% fread1(Format, FieldWidth, Suppress, Line, N, Results, AllFormat)
-%% fread1(Format, FieldWidth, Suppress, Line, N, Results)
+%% fread1(Format, FieldWidth, Suppress, Unicode, Line, N, Results, AllFormat)
+%% fread1(Format, FieldWidth, Suppress, Unicode, Line, N, Results)
 %%  The main dispatch function for the formatting commands. Done in two
 %%  stages so format commands that need no input can always be processed.
 
@@ -231,9 +231,8 @@ fread1([$s|Format], none, Sup, U, Line0, N0, Res) ->
 fread1([$s|Format], F, Sup, U, Line0, N, Res) ->
     {Line,Cs} = fread_chars(Line0, F, U),
     fread_string(Cs, Sup, U, Format, Line, N+F, Res);
-%% XXX:PaN Atoms still only latin1...
-fread1([$a|Format], none, Sup, false, Line0, N0, Res) ->
-    {Line,N,Cs} = fread_string_cs(Line0, N0, false),
+fread1([$a|Format], none, Sup, U, Line0, N0, Res) ->
+    {Line,N,Cs} = fread_string_cs(Line0, N0, U),
     fread_atom(Cs, Sup, Format, Line, N, Res);
 fread1([$a|Format], F, Sup, false, Line0, N, Res) ->
     {Line,Cs} = fread_chars(Line0, F, false),
diff --git a/lib/stdlib/test/io_SUITE.erl b/lib/stdlib/test/io_SUITE.erl
index fb62e3aa3c..ef3f0be5d7 100644
--- a/lib/stdlib/test/io_SUITE.erl
+++ b/lib/stdlib/test/io_SUITE.erl
@@ -2359,6 +2359,15 @@ otp_14285(_Config) ->
     "'кирилли́ческий атом'" = fmt("~tW", ['кирилли́ческий атом', 13]),
     [$',16#10FFFF,$'] = fmt("~tW", ['\x{10FFFF}', 13]),
 
+    {ok, [an_atom],[]} = io_lib:fread("~a", "an_atom"),
+    {ok, [an_atom],[]} = io_lib:fread("~ta", "an_atom"),
+    Str = "\"ab" ++ [1089] ++ "cd\"",
+    {ok, ["\"ab"], [1089]++"cd\""} = io_lib:fread("~s", Str),
+    {ok, ['\"ab'], [1089]++"cd\""} = io_lib:fread("~a", Str),
+    {ok,[Str], []} = io_lib:fread("~ts", Str),
+    {ok,[Atom],[]} = io_lib:fread("~ta", Str),
+    Str = atom_to_list(Atom),
+
     ok.
 
 latin1_fmt(Fmt, Args) ->