| #!/usr/bin/env escript |
| %% -*- erlang -*- |
| |
| % Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| % use this file except in compliance with the License. You may obtain a copy of |
| % the License at |
| % |
| % http://www.apache.org/licenses/LICENSE-2.0 |
| % |
| % Unless required by applicable law or agreed to in writing, software |
| % distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| % WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| % License for the specific language governing permissions and limitations under |
| % the License. |
| |
| main(_) -> |
| test_util:init_code_path(), |
| 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 |
| close -> ok |
| end. |
| |
| wait() -> |
| receive |
| {'DOWN', _, _, _, _} -> 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." |
| ), |
| |
| erlang:monitor(process, ChildPid1), |
| ChildPid1 ! close, |
| wait(), |
| |
| CheckFun = fun |
| (Iter, nil) -> |
| case couch_ref_counter:count(RefCtr) of |
| 1 -> Iter; |
| _ -> nil |
| end; |
| (_, Acc) -> |
| Acc |
| end, |
| Result = lists:foldl(CheckFun, nil, lists:seq(1, 10000)), |
| etap:isnt( |
| Result, |
| nil, |
| "The referer count was decremented automatically on process exit." |
| ), |
| |
| ok. |