tools: Correct a counting bug in Cover

See also PR #1641, https://github.com/erlang/otp/pull/1641.

The bug was introduced in commit ab435488a (Erlang/OTP 18).

2 files changed, 38 insertions, 8 deletions

diff --git a/lib/tools/src/cover.erl b/lib/tools/src/cover.erl
index 5517882ffa..4e64d7aa4e 100644
--- a/lib/tools/src/cover.erl
+++ b/lib/tools/src/cover.erl
@@ -2456,7 +2456,9 @@ do_analyse_to_file1(Module, OutFile, ErlFile, HTML) ->
 
 		    Pattern = {#bump{module=Module,line='$1',_='_'},'$2'},
 		    MS = [{Pattern,[{is_integer,'$1'},{'>','$1',0}],[{{'$1','$2'}}]}],
-		    CovLines = lists:keysort(1,ets:select(?COLLECTION_TABLE, MS)),
+                    CovLines0 =
+                        lists:keysort(1, ets:select(?COLLECTION_TABLE, MS)),
+                    CovLines = merge_dup_lines(CovLines0),
 		    print_lines(Module, CovLines, InFd, OutFd, 1, HTML),
 		    
 		    if HTML ->
@@ -2477,19 +2479,23 @@ do_analyse_to_file1(Module, OutFile, ErlFile, HTML) ->
 	    {error, {file, ErlFile, Reason}}
     end.
 
+merge_dup_lines(CovLines) ->
+    merge_dup_lines(CovLines, []).
+merge_dup_lines([{L, N}|T], [{L, NAcc}|TAcc]) ->
+    merge_dup_lines(T, [{L, NAcc + N}|TAcc]);
+merge_dup_lines([{L, N}|T], Acc) ->
+    merge_dup_lines(T, [{L, N}|Acc]);
+merge_dup_lines([], Acc) ->
+    lists:reverse(Acc).
 
 print_lines(Module, CovLines, InFd, OutFd, L, HTML) ->
     case file:read_line(InFd) of
 	eof ->
 	    ignore;
-	{ok,"%"++_=Line} ->		 %Comment line - not executed.
-	    ok = file:write(OutFd, [tab(),escape_lt_and_gt(Line, HTML)]),
-	    print_lines(Module, CovLines, InFd, OutFd, L+1, HTML);
 	{ok,RawLine} ->
 	    Line = escape_lt_and_gt(RawLine,HTML),
 	    case CovLines of
 	       [{L,N}|CovLines1] ->
-		    %% N = lists:foldl(fun([Ni], Nacc) -> Nacc+Ni end, 0, Ns),
                     if N=:=0, HTML=:=true ->
                            LineNoNL = Line -- "\n",
                            Str = "     0",
@@ -2508,7 +2514,7 @@ print_lines(Module, CovLines, InFd, OutFd, L, HTML) ->
                            ok = file:write(OutFd, [Str,fill3(),Line])
                     end,
 		    print_lines(Module, CovLines1, InFd, OutFd, L+1, HTML);
-		_ ->
+		_ ->                            %Including comment lines
 		    ok = file:write(OutFd, [tab(),Line]),
 		    print_lines(Module, CovLines, InFd, OutFd, L+1, HTML)
 	    end
diff --git a/lib/tools/test/cover_SUITE.erl b/lib/tools/test/cover_SUITE.erl
index 90e113c178..161b0105b9 100644
--- a/lib/tools/test/cover_SUITE.erl
+++ b/lib/tools/test/cover_SUITE.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 2001-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2001-2017. 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.
@@ -35,7 +35,7 @@ all() ->
                  distribution, reconnect, die_and_reconnect,
                  dont_reconnect_after_stop, stop_node_after_disconnect,
                  export_import, otp_5031, otp_6115,
-                 otp_8270, otp_10979_hanging_node],
+                 otp_8270, otp_10979_hanging_node, otp_14817],
     case whereis(cover_server) of
         undefined ->
             [coverage,StartStop ++ NoStartStop];
@@ -1574,6 +1574,30 @@ otp_10979_hanging_node(_Config) ->
 
     ok.
 
+otp_14817(Config) when is_list(Config) ->
+    Test = <<"-module(otp_14817).
+              -export([a/0, b/0, c/0, d/0]).
+              a() -> ok. b() -> ok. c() -> ok.
+              d() -> ok.
+             ">>,
+    File = cc_mod(otp_14817, Test, Config),
+    ok = otp_14817:a(),
+    ok = otp_14817:b(),
+    ok = otp_14817:c(),
+    ok = otp_14817:d(),
+    {ok,[{{otp_14817,3},1},
+         {{otp_14817,3},1},
+         {{otp_14817,3},1},
+         {{otp_14817,4},1}]} =
+        cover:analyse(otp_14817, calls, line),
+    {ok, CovOut} = cover:analyse_to_file(otp_14817),
+    {ok, Bin} = file:read_file(CovOut),
+    <<"3..|",_/binary>> = string:find(Bin, "3..|"),
+    <<"1..|",_/binary>> = string:find(Bin, "1..|"),
+    ok = file:delete(File),
+    ok = file:delete(CovOut),
+    ok.
+
 %% Take compiler options from beam in cover:compile_beam
 compile_beam_opts(Config) when is_list(Config) ->
     {ok, Cwd} = file:get_cwd(),