Copilot commented on code in PR #2708: URL: https://github.com/apache/groovy/pull/2708#discussion_r3574431031
########## src/test/groovy/groovy/lang/ExpandoMetaClassMixinConcurrencyTest.groovy: ########## @@ -0,0 +1,108 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + */ +package groovy.lang + +import org.codehaus.groovy.reflection.MixinInMetaClass +import org.junit.jupiter.api.Test +import org.junit.jupiter.api.Timeout + +import java.util.concurrent.CopyOnWriteArrayList +import java.util.concurrent.CyclicBarrier +import java.util.concurrent.TimeUnit +import java.util.concurrent.atomic.AtomicBoolean + +import static org.junit.jupiter.api.Assertions.assertNotNull +import static org.junit.jupiter.api.Assertions.assertTrue + +final class ExpandoMetaClassMixinConcurrencyTest { + + private static final int CATEGORY_COUNT = 40 + private static final int PRE_MIXED_COUNT = 8 + private static final int READER_COUNT = 3 + private static final int TIMEOUT_SECONDS = 30 + + static class Target {} + + // Adding a mixin (addMixinClass) mutates the backing mixin set while method + // dispatch iterates it (findMixinMethod). The set must tolerate that; a plain + // LinkedHashSet threw ConcurrentModificationException in the dispatching thread. + @Test + @Timeout(60) + void mixinAddIsSafeAgainstConcurrentDispatch() { + def loader = new GroovyClassLoader() + // distinct category classes so every mixin is a fresh structural add + def categories = (0..<CATEGORY_COUNT).collect { i -> + loader.parseClass("class Cat_$i { def catMethod_$i() { 'x' } }", "Cat_${i}.groovy") + } + + def emc = new ExpandoMetaClass(Target, false, true) + emc.initialize() + + // pre-populate so the readers always have something to iterate over + categories[0..<PRE_MIXED_COUNT].each { MixinInMetaClass.mixinClassesToMetaClass(emc, [it]) } + + def errors = new CopyOnWriteArrayList<Throwable>() + def stop = new AtomicBoolean(false) + def noArgs = new Class[0] + def barrier = new CyclicBarrier(READER_COUNT + 1) + + def readers = (1..READER_COUNT).collect { + Thread.start { + try { + barrier.await(TIMEOUT_SECONDS, TimeUnit.SECONDS) + while (!stop.get()) { + emc.findMixinMethod('noSuchMixinMethod', noArgs) + } Review Comment: The reader loop ignores thread interruption. If the test detects stuck threads and interrupts them, the readers will keep spinning until `stop` becomes true, which can leak threads when something goes wrong before `stop` is set (e.g. writer hang). Consider also terminating the loop when the thread is interrupted. ########## src/test/groovy/groovy/lang/ExpandoMetaClassMixinConcurrencyTest.groovy: ########## @@ -0,0 +1,108 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + */ +package groovy.lang + +import org.codehaus.groovy.reflection.MixinInMetaClass +import org.junit.jupiter.api.Test +import org.junit.jupiter.api.Timeout + +import java.util.concurrent.CopyOnWriteArrayList +import java.util.concurrent.CyclicBarrier +import java.util.concurrent.TimeUnit +import java.util.concurrent.atomic.AtomicBoolean + +import static org.junit.jupiter.api.Assertions.assertNotNull +import static org.junit.jupiter.api.Assertions.assertTrue + +final class ExpandoMetaClassMixinConcurrencyTest { + + private static final int CATEGORY_COUNT = 40 + private static final int PRE_MIXED_COUNT = 8 + private static final int READER_COUNT = 3 + private static final int TIMEOUT_SECONDS = 30 + + static class Target {} + + // Adding a mixin (addMixinClass) mutates the backing mixin set while method + // dispatch iterates it (findMixinMethod). The set must tolerate that; a plain + // LinkedHashSet threw ConcurrentModificationException in the dispatching thread. + @Test + @Timeout(60) + void mixinAddIsSafeAgainstConcurrentDispatch() { + def loader = new GroovyClassLoader() + // distinct category classes so every mixin is a fresh structural add + def categories = (0..<CATEGORY_COUNT).collect { i -> + loader.parseClass("class Cat_$i { def catMethod_$i() { 'x' } }", "Cat_${i}.groovy") + } + + def emc = new ExpandoMetaClass(Target, false, true) + emc.initialize() + + // pre-populate so the readers always have something to iterate over + categories[0..<PRE_MIXED_COUNT].each { MixinInMetaClass.mixinClassesToMetaClass(emc, [it]) } + + def errors = new CopyOnWriteArrayList<Throwable>() + def stop = new AtomicBoolean(false) + def noArgs = new Class[0] + def barrier = new CyclicBarrier(READER_COUNT + 1) + + def readers = (1..READER_COUNT).collect { + Thread.start { + try { + barrier.await(TIMEOUT_SECONDS, TimeUnit.SECONDS) + while (!stop.get()) { + emc.findMixinMethod('noSuchMixinMethod', noArgs) + } + } catch (Throwable t) { + errors << t + } finally { + stop.set(true) + } + } + } + def writer = Thread.start { + try { + barrier.await(TIMEOUT_SECONDS, TimeUnit.SECONDS) + categories[PRE_MIXED_COUNT..<CATEGORY_COUNT].each { + MixinInMetaClass.mixinClassesToMetaClass(emc, [it]) + } + } catch (Throwable t) { + errors << t + } finally { + stop.set(true) + } + } + + def threads = [writer, *readers] + threads.each { it.join(TimeUnit.SECONDS.toMillis(TIMEOUT_SECONDS)) } + def stuck = threads.findAll { it.alive } + stuck*.interrupt() + assertTrue(stuck.isEmpty(), "threads still running after ${TIMEOUT_SECONDS}s: $stuck") Review Comment: When threads are still alive after the join timeout, the test interrupts them but doesn't set `stop` first. Since the reader loop doesn't inherently respond to interrupts, setting `stop` here improves cleanup and reduces the risk of leaking threads into the rest of the test suite when this test fails. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
