Copilot commented on code in PR #2698: URL: https://github.com/apache/groovy/pull/2698#discussion_r3574174786
########## src/test/groovy/groovy/lang/ExpandoMetaClassMixinConcurrencyTest.groovy: ########## @@ -0,0 +1,90 @@ +/* + * 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 java.util.concurrent.CopyOnWriteArrayList +import java.util.concurrent.CyclicBarrier +import java.util.concurrent.atomic.AtomicBoolean + +import static org.junit.jupiter.api.Assertions.assertTrue + +final class ExpandoMetaClassMixinConcurrencyTest { + + 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 from the dispatching thread. + @Test + void mixinAddIsSafeAgainstConcurrentDispatch() { + def loader = new GroovyClassLoader() + // distinct category classes so every mixin is a fresh structural add + def categories = (0..<160).collect { i -> + loader.parseClass("class Cat_${i} { def catMethod_${i}() { 'x' } }", "Cat_${i}.groovy") + } + + def emc = new ExpandoMetaClass(Target, false, true) + emc.initialize() + + // pre-grow the set so each iteration spans a wide window + (0..<40).each { MixinInMetaClass.mixinClassesToMetaClass(emc, [categories[it]]) } + + def errors = new CopyOnWriteArrayList<Throwable>() + def stop = new AtomicBoolean(false) + def emptyArgs = new Class[0] + def barrier = new CyclicBarrier(5) + + def readers = (1..4).collect { + Thread.start { + try { + barrier.await() Review Comment: `barrier.await()` has no timeout, so if one party fails to reach the barrier the test can hang indefinitely in CI. Use a bounded await to fail fast instead of blocking forever. ########## src/test/groovy/groovy/lang/ExpandoMetaClassMixinConcurrencyTest.groovy: ########## @@ -0,0 +1,90 @@ +/* + * 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 java.util.concurrent.CopyOnWriteArrayList +import java.util.concurrent.CyclicBarrier +import java.util.concurrent.atomic.AtomicBoolean + +import static org.junit.jupiter.api.Assertions.assertTrue + +final class ExpandoMetaClassMixinConcurrencyTest { + + 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 from the dispatching thread. + @Test + void mixinAddIsSafeAgainstConcurrentDispatch() { + def loader = new GroovyClassLoader() + // distinct category classes so every mixin is a fresh structural add + def categories = (0..<160).collect { i -> + loader.parseClass("class Cat_${i} { def catMethod_${i}() { 'x' } }", "Cat_${i}.groovy") + } + + def emc = new ExpandoMetaClass(Target, false, true) + emc.initialize() + + // pre-grow the set so each iteration spans a wide window + (0..<40).each { MixinInMetaClass.mixinClassesToMetaClass(emc, [categories[it]]) } + + def errors = new CopyOnWriteArrayList<Throwable>() + def stop = new AtomicBoolean(false) + def emptyArgs = new Class[0] + def barrier = new CyclicBarrier(5) + + def readers = (1..4).collect { + Thread.start { + try { + barrier.await() + while (!stop.get()) { + emc.findMixinMethod('noSuchMixinMethod', emptyArgs) + } + } catch (Throwable t) { + errors << t + } finally { + stop.set(true) + } + } + } + def writer = Thread.start { + try { + barrier.await() Review Comment: `barrier.await()` has no timeout here; if any reader thread fails before reaching the barrier, this writer thread can block forever. Prefer a bounded await to prevent test suite hangs. ########## src/test/groovy/groovy/lang/ExpandoMetaClassMixinConcurrencyTest.groovy: ########## @@ -0,0 +1,90 @@ +/* + * 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 java.util.concurrent.CopyOnWriteArrayList +import java.util.concurrent.CyclicBarrier +import java.util.concurrent.atomic.AtomicBoolean + +import static org.junit.jupiter.api.Assertions.assertTrue + +final class ExpandoMetaClassMixinConcurrencyTest { + + 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 from the dispatching thread. + @Test + void mixinAddIsSafeAgainstConcurrentDispatch() { + def loader = new GroovyClassLoader() + // distinct category classes so every mixin is a fresh structural add + def categories = (0..<160).collect { i -> + loader.parseClass("class Cat_${i} { def catMethod_${i}() { 'x' } }", "Cat_${i}.groovy") + } + + def emc = new ExpandoMetaClass(Target, false, true) + emc.initialize() + + // pre-grow the set so each iteration spans a wide window + (0..<40).each { MixinInMetaClass.mixinClassesToMetaClass(emc, [categories[it]]) } + + def errors = new CopyOnWriteArrayList<Throwable>() + def stop = new AtomicBoolean(false) + def emptyArgs = new Class[0] + def barrier = new CyclicBarrier(5) + + def readers = (1..4).collect { + Thread.start { + try { + barrier.await() + while (!stop.get()) { + emc.findMixinMethod('noSuchMixinMethod', emptyArgs) + } + } catch (Throwable t) { + errors << t + } finally { + stop.set(true) + } + } + } + def writer = Thread.start { + try { + barrier.await() + for (int i = 40; i < categories.size() && !stop.get(); i++) { + MixinInMetaClass.mixinClassesToMetaClass(emc, [categories[i]]) + } + } catch (Throwable t) { + errors << t + } finally { + stop.set(true) + } + } + + writer.join() + stop.set(true) + readers*.join() Review Comment: The thread joins are unbounded (`join()` / `readers*.join()`), so if a thread gets stuck (e.g., at the barrier) the test can hang the entire build. Use join timeouts and interrupt any remaining live threads. -- 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]
