epp: Allow user to set source name independently of input file name

Note that this does *not* affect -include()'d files or the -file()
directive.

4 files changed, 57 insertions, 7 deletions

diff --git a/lib/stdlib/doc/src/epp.xml b/lib/stdlib/doc/src/epp.xml
index 1dc0161398..d803d259aa 100644
--- a/lib/stdlib/doc/src/epp.xml
+++ b/lib/stdlib/doc/src/epp.xml
@@ -124,6 +124,10 @@
       <fsummary>Open a file for preprocessing.</fsummary>
       <desc>
         <p>Opens a file for preprocessing.</p>
+        <p>If you want to change the file name of the implicit -file()
+          attributes inserted during preprocessing, you can do with
+          <c>{source_name, <anno>SourceName</anno>}</c>. If unset it will
+          default to the name of the opened file.</p>
         <p>If <c>extra</c> is specified in
           <c><anno>Options</anno></c>, the return value is
           <c>{ok, <anno>Epp</anno>, <anno>Extra</anno>}</c> instead
@@ -169,6 +173,10 @@
         <p>Preprocesses and parses an Erlang source file.
           Notice that tuple <c>{eof, <anno>Line</anno>}</c> returned at the
           end of the file is included as a "form".</p>
+        <p>If you want to change the file name of the implicit -file()
+          attributes inserted during preprocessing, you can do with
+          <c>{source_name, <anno>SourceName</anno>}</c>. If unset it will
+          default to the name of the opened file.</p>
         <p>If <c>extra</c> is specified in
          <c><anno>Options</anno></c>, the return value is
          <c>{ok, [<anno>Form</anno>], <anno>Extra</anno>}</c> instead
diff --git a/lib/stdlib/src/epp.erl b/lib/stdlib/src/epp.erl
index cc34d4bdd3..181a524db6 100644
--- a/lib/stdlib/src/epp.erl
+++ b/lib/stdlib/src/epp.erl
@@ -117,6 +117,7 @@ open(Name, File, StartLocation, Path, Pdm) ->
 		  {'ok', Epp} | {'ok', Epp, Extra} | {'error', ErrorDescriptor} when
       Options :: [{'default_encoding', DefEncoding :: source_encoding()} |
 		  {'includes', IncludePath :: [DirectoryName :: file:name()]} |
+		  {'source_name', SourceName :: file:name()} |
 		  {'macros', PredefMacros :: macros()} |
 		  {'name',FileName :: file:name()} |
 		  'extra'],
@@ -248,6 +249,7 @@ parse_file(Ifile, Path, Predefs) ->
         {'ok', [Form]} | {'ok', [Form], Extra} | {error, OpenError} when
       FileName :: file:name(),
       Options :: [{'includes', IncludePath :: [DirectoryName :: file:name()]} |
+		  {'source_name', SourceName :: file:name()} |
 		  {'macros', PredefMacros :: macros()} |
 		  {'default_encoding', DefEncoding :: source_encoding()} |
 		  'extra'],
@@ -540,9 +542,10 @@ server(Pid, Name, Options, #epp{pre_opened=PreOpened}=St) ->
             init_server(Pid, Name, Options, St)
     end.
 
-init_server(Pid, Name, Options, St0) ->
+init_server(Pid, FileName, Options, St0) ->
+    SourceName = proplists:get_value(source_name, Options, FileName),
     Pdm = proplists:get_value(macros, Options, []),
-    Ms0 = predef_macros(Name),
+    Ms0 = predef_macros(FileName),
     case user_predef(Pdm, Ms0) of
 	{ok,Ms1} ->
 	    #epp{file = File, location = AtLocation} = St0,
@@ -552,14 +555,14 @@ init_server(Pid, Name, Options, St0) ->
             epp_reply(Pid, {ok,self(),Encoding}),
             %% ensure directory of current source file is
             %% first in path
-            Path = [filename:dirname(Name) |
+            Path = [filename:dirname(FileName) |
                     proplists:get_value(includes, Options, [])],
-            St = St0#epp{delta=0, name=Name, name2=Name,
+            St = St0#epp{delta=0, name=SourceName, name2=SourceName,
 			 path=Path, macs=Ms1,
 			 default_encoding=DefEncoding},
             From = wait_request(St),
             Anno = erl_anno:new(AtLocation),
-            enter_file_reply(From, file_name(Name), Anno,
+            enter_file_reply(From, file_name(SourceName), Anno,
 			     AtLocation, code),
             wait_req_scan(St);
 	{error,E} ->
diff --git a/lib/stdlib/test/epp_SUITE.erl b/lib/stdlib/test/epp_SUITE.erl
index a3e294ffea..0ac99ad03a 100644
--- a/lib/stdlib/test/epp_SUITE.erl
+++ b/lib/stdlib/test/epp_SUITE.erl
@@ -29,7 +29,7 @@
          otp_8562/1, otp_8665/1, otp_8911/1, otp_10302/1, otp_10820/1,
          otp_11728/1, encoding/1, extends/1,  function_macro/1,
 	 test_error/1, test_warning/1, otp_14285/1,
-	 test_if/1]).
+	 test_if/1,source_name/1]).
 
 -export([epp_parse_erl_form/2]).
 
@@ -70,7 +70,7 @@ all() ->
      overload_mac, otp_8388, otp_8470, otp_8562,
      otp_8665, otp_8911, otp_10302, otp_10820, otp_11728,
      encoding, extends, function_macro, test_error, test_warning,
-     otp_14285, test_if].
+     otp_14285, test_if, source_name].
 
 groups() -> 
     [{upcase_mac, [], [upcase_mac_1, upcase_mac_2]},
@@ -1702,6 +1702,18 @@ function_macro(Config) ->
 
     ok.
 
+source_name(Config) when is_list(Config) ->
+    DataDir = proplists:get_value(data_dir, Config),
+    File = filename:join(DataDir, "source_name.erl"),
+
+    source_name_1(File, "/test/gurka.erl"),
+    source_name_1(File, "gaffel.erl"),
+
+    ok.
+
+source_name_1(File, Expected) ->
+    Res = epp:parse_file(File, [{source_name, Expected}]),
+    {ok, [{attribute,_,file,{Expected,_}} | _Forms]} = Res.
 
 check(Config, Tests) ->
     eval_tests(Config, fun check_test/2, Tests).
diff --git a/lib/stdlib/test/epp_SUITE_data/source_name.erl b/lib/stdlib/test/epp_SUITE_data/source_name.erl
new file mode 100644
index 0000000000..71ad2dddb9
--- /dev/null
+++ b/lib/stdlib/test/epp_SUITE_data/source_name.erl
@@ -0,0 +1,27 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 2018. 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(source_name).
+-export([ok/0]).
+
+%% Changing source name should not affect headers
+-include("bar.hrl").
+
+ok() -> ok.