Allow persistent option on set_env/4 and unset_env/3

An environment key set with the persistent option will not
be overridden by the ones configured in the application resource
file on load. This means persistent values will stick after the
application is loaded and also on application reload.

1 files changed, 47 insertions, 2 deletions

diff --git a/lib/kernel/test/application_SUITE.erl b/lib/kernel/test/application_SUITE.erl
index 9ec8a15861..ff62297f2d 100644
--- a/lib/kernel/test/application_SUITE.erl
+++ b/lib/kernel/test/application_SUITE.erl
@@ -33,7 +33,7 @@
 	 permit_false_start_local/1, permit_false_start_dist/1, script_start/1, 
 	 nodedown_start/1, init2973/0, loop2973/0, loop5606/1]).
 
--export([config_change/1,
+-export([config_change/1, persistent_env/1,
 	 distr_changed_tc1/1, distr_changed_tc2/1,
 	 ensure_started/1, ensure_all_started/1,
 	 shutdown_func/1, do_shutdown/1, shutdown_timeout/1]).
@@ -53,7 +53,8 @@ all() ->
      load_use_cache, ensure_started, {group, reported_bugs}, start_phases,
      script_start, nodedown_start, permit_false_start_local,
      permit_false_start_dist, get_key, get_env, ensure_all_started,
-     {group, distr_changed}, config_change, shutdown_func, shutdown_timeout].
+     {group, distr_changed}, config_change, shutdown_func, shutdown_timeout,
+     persistent_env].
 
 groups() -> 
     [{reported_bugs, [],
@@ -1987,6 +1988,50 @@ get_appls([_ | T], Res) ->
 get_appls([], Res) ->
     Res.
 
+persistent_env(suite) ->
+    [];
+persistent_env(doc) ->
+    ["Test set_env/4 and unset_env/3 with persistent true"];
+persistent_env(Conf) when is_list(Conf) ->
+    ok = application:set_env(appinc, own2, persist, [{persistent, true}]),
+    ok = application:set_env(appinc, key1, persist, [{persistent, true}]),
+
+    %% own_env1 and own2 are set in appinc
+    ok = application:load(appinc()),
+    {ok, value1} = application:get_env(appinc, own_env1),
+    {ok, persist} = application:get_env(appinc, own2),
+    {ok, persist} = application:get_env(appinc, key1),
+
+    %% Changing the environment after loaded reflects and should persist
+    ok = application:set_env(appinc, own_env1, persist, [{persistent, true}]),
+    {ok, persist} = application:get_env(appinc, own_env1),
+    {ok, persist} = application:get_env(appinc, own2),
+    {ok, persist} = application:get_env(appinc, key1),
+
+    %% On reload, own_env1, own2 and key1 should all persist
+    ok = application:unload(appinc),
+    ok = application:load(appinc()),
+    {ok, persist} = application:get_env(appinc, own_env1),
+    {ok, persist} = application:get_env(appinc, own2),
+    {ok, persist} = application:get_env(appinc, key1),
+
+    %% Unset own_env1 and key1, own2 should still persist
+    ok = application:unset_env(appinc, own_env1, [{persistent, true}]),
+    ok = application:unset_env(appinc, key1, [{persistent, true}]),
+    undefined = application:get_env(appinc, own_env1),
+    {ok, persist} = application:get_env(appinc, own2),
+    undefined = application:get_env(appinc, key1),
+
+    %% own_env1 should be back to its application value on reload
+    ok = application:unload(appinc),
+    ok = application:load(appinc()),
+    {ok, value1} = application:get_env(appinc, own_env1),
+    {ok, persist} = application:get_env(appinc, own2),
+    undefined = application:get_env(appinc, key1),
+
+    %% Clean up
+    ok = application:unload(appinc).
+
 %%%-----------------------------------------------------------------
 %%% Tests the 'shutdown_func' kernel config parameter
 %%%-----------------------------------------------------------------