Ignore undefined calls to OTP 18 time api in app suite

So that the xref testcase is independent of the release it's run on. The
code uses the new time api if available, so as to be forward compatible.

1 files changed, 37 insertions, 6 deletions

diff --git a/lib/diameter/test/diameter_app_SUITE.erl b/lib/diameter/test/diameter_app_SUITE.erl
index f68a18b5c2..cf34c762e1 100644
--- a/lib/diameter/test/diameter_app_SUITE.erl
+++ b/lib/diameter/test/diameter_app_SUITE.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2014. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2015. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -187,15 +187,14 @@ xref(Config) ->
 
     xref:stop(XRef),
 
+    Rel = release(),  %% otp_release-ish
+
     %% Only care about calls from our own application.
-    [] = lists:filter(fun({{F,_,_},{T,_,_}}) ->
+    [] = lists:filter(fun({{F,_,_} = From, {_,_,_} = To}) ->
                               lists:member(F, Mods)
-                                  andalso {F,T} /= {diameter_tcp, ssl}
+                                  andalso not ignored(From, To, Rel)
                       end,
                       Undefs),
-    %% diameter_tcp does call ssl despite the latter not being listed
-    %% as a dependency in the app file since ssl is only required for
-    %% TLS security: it's up to a client who wants TLS to start ssl.
 
     %% Ensure that only runtime or info modules call runtime modules.
     %% It's not strictly necessary that diameter compiler modules not
@@ -214,6 +213,38 @@ xref(Config) ->
     [] = lists:filter(fun(M) -> not lists:member(app(M), Deps) end,
                       RTdeps -- Mods).
 
+ignored({FromMod,_,_}, {ToMod,_,_} = To, Rel)->
+    %% diameter_tcp does call ssl despite the latter not being listed
+    %% as a dependency in the app file since ssl is only required for
+    %% TLS security: it's up to a client who wants TLS to start ssl.
+    %% The OTP 18 time api is also called if it exists, so that the
+    %% same code can be run on older releases.
+    {FromMod, ToMod} == {diameter_tcp, ssl}
+        orelse (FromMod == diameter_lib
+                andalso Rel < 18
+                andalso lists:member(To, time_api())).
+
+%% New time api in OTP 18.
+time_api() ->
+    [{erlang, F, A} || {F,A} <- [{convert_time_resolution,3},
+                                 {monotonic_time,0},
+                                 {monotonic_time,1},
+                                 {time_offset,0},
+                                 {time_offset,1},
+                                 {time_resolution,0},
+                                 {timestamp,0},
+                                 {unique_integer,0},
+                                 {unique_integer,1}]].
+
+release() ->
+    Rel = erlang:system_info(otp_release),
+    try list_to_integer(Rel) of
+        N -> N
+    catch
+        error:_ ->
+            0  %% aka < 17
+    end.
+
 unversion(App) ->
     T = lists:dropwhile(fun is_vsn_ch/1, lists:reverse(App)),
     lists:reverse(case T of [$-|TT] -> TT; _ -> T end).