stdlib: Fix a minor issue with the qlc suite

When comparing the process dictionary before and after a test, only
(a sorted list of) qlc keys are compared.

1 files changed, 14 insertions, 2 deletions

diff --git a/lib/stdlib/test/qlc_SUITE.erl b/lib/stdlib/test/qlc_SUITE.erl
index 5e9e03e410..949142ec77 100644
--- a/lib/stdlib/test/qlc_SUITE.erl
+++ b/lib/stdlib/test/qlc_SUITE.erl
@@ -7871,7 +7871,7 @@ run_test(Config, Extra, {cres, Body, Opts, ExpectedCompileReturn}) ->
     {module, _} = code:load_abs(AbsFile, Mod),
 
     Ms0 = erlang:process_info(self(),messages),
-    Before = {{get(), lists:sort(ets:all()), Ms0}, pps()},
+    Before = {{lget(), lists:sort(ets:all()), Ms0}, pps()},
 
     %% Prepare the check that the qlc module does not call qlc_pt.
     _ = [unload_pt() || {file, Name} <- [code:is_loaded(qlc_pt)], 
@@ -7903,7 +7903,7 @@ run_test(Config, Extra, Body) ->
 
 wait_for_expected(R, {Strict0,PPS0}=Before, SourceFile, Wait) ->
     Ms = erlang:process_info(self(),messages),
-    After = {_,PPS1} = {{get(), lists:sort(ets:all()), Ms}, pps()},
+    After = {_,PPS1} = {{lget(), lists:sort(ets:all()), Ms}, pps()},
     case {R, After} of
         {ok, Before} ->
             ok;
@@ -7931,6 +7931,18 @@ wait_for_expected(R, {Strict0,PPS0}=Before, SourceFile, Wait) ->
             expected({ok,Before}, {R,After}, SourceFile)
     end.
 
+%% The qlc modules uses the process dictionary for storing names of files.
+lget() ->
+    lists:sort([T || {K, _} = T <- get(), is_qlc_key(K)]).
+
+%% Copied from the qlc module.
+-define(LCACHE_FILE(Ref), {Ref, '$_qlc_cache_tmpfiles_'}).
+-define(MERGE_JOIN_FILE, '$_qlc_merge_join_tmpfiles_').
+
+is_qlc_key(?LCACHE_FILE(_)) -> true;
+is_qlc_key(?MERGE_JOIN_FILE) -> true;
+is_qlc_key(_) -> false.
+
 unload_pt() ->
     erlang:garbage_collect(), % get rid of references to qlc_pt...
     _ = code:purge(qlc_pt),