Adding tests for couch_ref_counter.erl

Thanks Bob Dionne



git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@788253 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 93 insertions, 0 deletions

diff --git a/test/etap/100-ref-counter.t b/test/etap/100-ref-counter.t
new file mode 100755
index 00000000..746b70a9
--- /dev/null
+++ b/test/etap/100-ref-counter.t
@@ -0,0 +1,93 @@
+#!/usr/bin/env escript
+%% -*- erlang -*-
+
+main(_) ->
+    code:add_pathz("src/couchdb"),
+    etap:plan(8),
+    case (catch test()) of
+        ok ->
+            etap:end_tests();
+        Other ->
+            etap:diag(io_lib:format("Test died abnormally: ~p", [Other])),
+            etap:bail(Other)
+    end,
+    ok.
+
+loop() ->
+    receive
+    {ping, From} ->
+        From ! pong
+    end.
+
+wait() ->
+    receive
+        _ ->
+            ok
+    after
+        1000 ->
+            throw(timeout_error)
+    end.    
+
+test() ->   
+    {ok, RefCtr} = couch_ref_counter:start([]),
+
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        1,
+        "A ref_counter is initialized with the calling process as a referer."
+    ),
+
+    ChildPid1 = spawn(fun() -> loop() end),
+
+    % This is largely implicit in that nothing else breaks
+    % as ok is just returned from gen_server:cast()
+    etap:is(
+        couch_ref_counter:drop(RefCtr, ChildPid1),
+        ok,
+        "Dropping an unknown Pid is ignored."
+    ),
+
+    couch_ref_counter:add(RefCtr, ChildPid1),
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        2,
+        "Adding a Pid to the ref_counter increases it's count."
+    ),
+
+    couch_ref_counter:add(RefCtr, ChildPid1),
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        2,
+        "Readding the same Pid maintains the count but increments it's refs."
+    ),
+
+    couch_ref_counter:drop(RefCtr, ChildPid1),
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        2,
+        "Droping the doubly added Pid only removes a ref, not a referer."
+    ),
+    
+    couch_ref_counter:drop(RefCtr, ChildPid1),
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        1,
+        "Dropping the second ref drops the referer."
+    ),
+
+    couch_ref_counter:add(RefCtr, ChildPid1),
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        2,
+        "Sanity checking that the Pid was re-added."
+    ),
+    
+    ChildPid1 ! {ping, self()},
+    wait(),
+    etap:is(
+        couch_ref_counter:count(RefCtr),
+        1,
+        "The referer count was decremented automatically on process exit."
+    ),
+
+    ok.