build cache support for reportScoverage tasks

[dsilvasc]

The reportScoverage task runs on every ./gradlew check invocation, even when running it multiple times in sequence without any changes to the source.

Would it be possible to make it work with up-to-date checks and the gradle build cache?

> Task :testing:reportScoverage
Caching disabled for task ':testing:reportScoverage': Caching has not been enabled for the task
Task ':testing:reportScoverage' is not up-to-date because:
  Task has not declared any outputs despite executing actions.
Starting process 'command '/Library/Java/JavaVirtualMachines/jdk1.8.0_161.jdk/Contents/Home/bin/java''. ... Command: /Library/Java/JavaVirtualMachines/jdk1.8.0_161.jdk/Contents/Home/bin/java ... org.scoverage.SingleReportApp ...
[scoverage] Generating scoverage reports...
...
:testing:reportScoverage (Thread[Task worker for ':' Thread 3,5,main]) completed. Took 1.531 secs.

[maiflai]

Please could you try again using version 2.2.0 of this plugin? I hope I've managed to configure it correctly.

Thanks,
Stu

[dsilvasc]

Looks like the up-to-date check works:

> Task :common:concurrent:reportScoverage UP-TO-DATE
Skipping task ':common:concurrent:reportScoverage' as it is up-to-date.
:common:concurrent:reportScoverage (Thread[Task worker for ':',5,main]) completed. Took 0.003 secs.

Caching doesn't:

> Task :common:concurrent:reportScoverage UP-TO-DATE
Build cache key for task ':common:concurrent:reportScoverage' is 3d1438d43d16ad3b7b91d94f2a0bf6ae
Caching disabled for task ':common:concurrent:reportScoverage': Caching has not been enabled for the task

Also upgrading from 2.1.0 to 2.2.0 breaks the gradle ScalaStyle plugin:

> Task :common:concurrent:scalaStyle FAILED
Task ':common:concurrent:scalaStyle' is not up-to-date because:
  Task ':common:concurrent:scalaStyle' class path has changed from b2e5ddeb6fd334f3d63d0ac350925277 to 666042731c7bd00bfa95c6eb7157d7c7.
:common:concurrent:scalaStyle (Thread[Task worker for ':',5,main]) completed. Took 0.058 secs.

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':common:concurrent:scalaStyle'.
> scala/Product$class

* Try:
Run with --debug option to get more log output. Run with --scan to get full insights.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':common:concurrent:scalaStyle'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:103)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:73)
        at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
        at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:59)
        at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:59)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:101)
        at org.gradle.api.internal.tasks.execution.FinalizeInputFilePropertiesTaskExecuter.execute(FinalizeInputFilePropertiesTaskExecuter.java:44)
        at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:91)
        at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:62)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:59)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
        at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:256)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:317)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:309)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:185)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:97)
        at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:249)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:238)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:663)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:596)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
        at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
        at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NoClassDefFoundError: scala/Product$class
        at scala.xml.NamespaceBinding.<init>(NamespaceBinding.scala:24)
        at scala.xml.TopScope$.<init>(TopScope.scala:17)
        at scala.xml.TopScope$.<clinit>(TopScope.scala)
        at scala.xml.factory.XMLLoader$class.loadXML(XMLLoader.scala:40)
        at scala.xml.XML$.loadXML(XML.scala:60)
        at scala.xml.factory.XMLLoader$class.loadFile(XMLLoader.scala:50)
        at scala.xml.XML$.loadFile(XML.scala:60)
        at org.scalastyle.ScalastyleConfiguration$.readFromXml(ScalastyleConfiguration.scala:87)
        at org.scalastyle.ScalastyleConfiguration.readFromXml(ScalastyleConfiguration.scala)
        at org.scalastyle.ScalastyleConfiguration$readFromXml.call(Unknown Source)
        at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:125)
        at org.github.ngbinh.scalastyle.ScalaStyleTask.scalaStyle(ScalaStyleTask.groovy:80)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.doExecute(StandardTaskAction.java:46)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
        at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:794)
        at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:761)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:124)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:317)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:309)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:185)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:97)
        at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:113)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:95)
        ... 32 more
Caused by: java.lang.ClassNotFoundException: scala.Product$class
        at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        ... 64 more

My buildSrc/build.gradle.kts has this:

repositories {
  // https://github.com/ngbinh/gradle-scalastyle-plugin/issues/39
  maven {
    name = "ngbinh"
    url = uri("https://dl.bintray.com/ngbinh/maven")
  }
  // https://plugins.gradle.org/plugin/org.scoverage
  maven {
    name = "gradle-plugins"
    url = uri("https://plugins.gradle.org/m2/")
  }
}

dependencies {
  "implementation"("org.github.ngbinh.scalastyle:gradle-scalastyle-plugin_2.12:1.0.1")
  "implementation"("gradle.plugin.org.scoverage:gradle-scoverage:2.2.0")
}

And my root build.gradle.kts includes this:

val scoverageVersion = "1.3.1"
val scalaRelease = "2.12.6"

val scalaLibrary = "org.scala-lang:scala-library:$scalaRelease"
val scalaCompiler = "org.scala-lang:scala-compiler:$scalaRelease"
val scalaReflect = "org.scala-lang:scala-reflect:$scalaRelease"

// Don't manipulate versions for gradle internals: https://github.com/typesafehub/zinc/issues/87
val blacklistConfigs = setOf("zinc", "checkstyle", "scoverage", "scalaStyle")

subprojects {
  apply<org.gradle.api.plugins.scala.ScalaPlugin>()
  apply<org.github.ngbinh.scalastyle.ScalaStylePlugin>()
  apply<org.scoverage.ScoveragePlugin>()

  configurations.all {
    if (!blacklistConfigs.contains(name)) {
      resolutionStrategy {
        preferProjectModules()
        // Enforce consistent third-party package versions across all projects in this repository.
        // This should avoid issues where a common module is built against one version of a third-party library,
        // then deployed as part of a service to run against a different version.
        force(scalaLibrary)
        force(scalaCompiler)
        force(scalaReflect)
      }
    }
  }
  dependencies {
    "compile"(scalaLibrary)
    "compile"(scalaCompiler)
    "compile"(scalaReflect)
    "scoverage"("org.scoverage:scalac-scoverage-plugin_2.12:$scoverageVersion")
    "scoverage"("org.scoverage:scalac-scoverage-runtime_2.12:$scoverageVersion")
  }
}

Running gradle a second time yields the same error as ngbinh/gradle-scalastyle-plugin#38

[maiflai]

Caching doesn't

Sorry, I didn't realise they were different things. I think it's a case of just adding an annotation here, so I'll see about getting that done.

Also upgrading from 2.1.0 to 2.2.0 breaks the gradle ScalaStyle plugin

Interesting, given the other conversation about this plugin trying not to modify the Gradle classpath.

I expect that you should not be adding this build plugin to the implementation configuration?

i.e. remove this line implementation ("gradle.plugin.org.scoverage:gradle-scoverage:2.2.0")

[dsilvasc]

Thanks for looking into this.

The line implementation ("gradle.plugin.org.scoverage:gradle-scoverage:2.2.0") is in buildSrc so it's visible to custom plugins (it behaves like buildscript dependencies).

Here's a minimal repro: https://github.com/dsilvasc/repro-gradle-scoverage-74

I think the issue is caused by the gradle-scoverage dependency on org.scoverage:scalac-scoverage-plugin_2.11:1.1.1 in line 47 here:

gradle-scoverage/build.gradle

Line 47 in 12b196a

scoverage "org.scoverage:scalac-scoverage-plugin_2.11:1.1.1"

If I exclude that, then the problem goes away.

[maiflai]

Ah, that's odd.

The dependency in my build.gradle is essentially an api dependency for the plugin; the implementation is intended to be sourced from the scoverage configuration in the consumer's project.

The pom published to maven central doesn't have any dependency: http://search.maven.org/remotecontent?filepath=org/scoverage/gradle-scoverage/2.2.0/gradle-scoverage-2.2.0.pom

The pom published to the plugins repo looks entiely different:
https://plugins.gradle.org/m2/gradle/plugin/org/scoverage/gradle-scoverage/2.2.0/gradle-scoverage-2.2.0.pom

I'll see if I can find out why tomorrow, but for the moment please use maven central?

Thanks,
Stu.

[dsilvasc]

Thanks, that works too :)

[maiflai]

2.3.0 published to the plugin portal with cachable tasks and without dependencies - please would you be able to have a look?

Thanks,
Stu

[dsilvasc]

@maiflai Sorry for the delay here -- I've upgraded to gradle.plugin.org.scoverage:gradle-scoverage:2.3.0 and caching works for most tasks:

> Task :common:concurrent:compileScala FROM-CACHE
> Task :common:concurrent:processResources NO-SOURCE
> Task :common:concurrent:classes UP-TO-DATE
> Task :common:concurrent:compileScoverageJava NO-SOURCE
> Task :common:concurrent:compileScoverageScala FROM-CACHE
> Task :common:concurrent:processScoverageResources NO-SOURCE
> Task :common:concurrent:scoverageClasses UP-TO-DATE
> Task :common:concurrent:compileTestJava NO-SOURCE
> Task :common:concurrent:compileTestScala FROM-CACHE
> Task :common:concurrent:processTestResources NO-SOURCE
> Task :common:concurrent:testClasses UP-TO-DATE
> Task :common:concurrent:compileTestScoverageJava NO-SOURCE
> Task :common:concurrent:compileTestScoverageScala FROM-CACHE
> Task :common:concurrent:processTestScoverageResources NO-SOURCE
> Task :common:concurrent:testScoverageClasses UP-TO-DATE
> Task :common:concurrent:testScoverage
> Task :common:concurrent:reportScoverage FROM-CACHE

It just didn't work for testScoverage:

> Task :common:concurrent:testScoverage
Build cache key for task ':common:concurrent:testScoverage' is 5c8c3036187a20d226721614b82904b2
Caching disabled for task ':common:concurrent:testScoverage': Gradle does not know how file 'build/scoverage/scoverage.coverage.xml' was created (output property '$1'). Task output caching requires exclusive access to output paths to guarantee correctness.
Task ':common:concurrent:testScoverage' is not up-to-date because:
  Output property '$1' file common/concurrent/build/scoverage/scoverage.measurements.11 has been removed.
  Output property '$2' file common/concurrent/build/scoverage/scoverage.measurements.11 has been removed.
  Output property 'binResultsDir' file common/concurrent/build/test-results/testScoverage/binary has been removed.
Starting process 'Gradle Test Executor 5'. Working directory: common/concurrent Command: /Library/Java/JavaVirtualMachines/jdk1.8.0_161.jdk/Contents/Home/bin/java -Djava.security.manager=worker.org.gradle.process.internal.worker.child.BootstrapSecurityManager -Dorg.gradle.native=false -Dfile.encoding=UTF-8 -Duser.country=US -Duser.language=en -Duser.variant -ea -cp ~/.gradle/caches/4.10/workerMain/gradle-worker.jar worker.org.gradle.process.internal.worker.GradleWorkerMain 'Gradle Test Executor 5'
Successfully started process 'Gradle Test Executor 5'
Finished generating test XML results (0.001 secs) into: common/concurrent/build/test-results/testScoverage
Generating HTML test report...
Finished generating test html results (0.003 secs) into: common/concurrent/build/reports/tests/testScoverage
:common:concurrent:testScoverage (Thread[Task worker for ':',5,main]) completed. Took 1.419 secs.
:common:concurrent:reportScoverage (Thread[Task worker for ':',5,main]) started.

[maiflai]

Hi,

Compilation writes the scoverage.coverage.xml; it contains the statement identifiers.

Test writes a set of measurement files which reference the statement identifiers.

It looks like Gradle is complaining that the test task claims to own the data directory, but the scoverage.coverage.xml file was created by something else.

I'll see if I can work around it.

[maiflai]

Please could you re-test this with the new 2.4.0 release?

Thanks,
Stu

[maiflai]

Please can I close this issue?

[dsilvasc]

Hi Stu,

Sorry for missing the comment about 2.4.0. I just tried it and this is what I get:

> Task :common:concurrent:testScoverage
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property nonEmptyCandidateClassFiles (RelativePathInput) for task ':common:concurrent:testScoverage'
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property org.gradle.api.internal.tasks.NonCacheableTaskOutputPropertySpec@4c0c82ab for task ':common:concurrent:testScoverage'
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property binResultsDir (Output) for task ':common:concurrent:testScoverage'
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property reports.enabledReports.html.destination (Output) for task ':common:concurrent:testScoverage'
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property reports.enabledReports.junitXml.destination (Output) for task ':common:concurrent:testScoverage'
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property reports.html.destination (Output) for task ':common:concurrent:testScoverage'
09:00:41.508 [DEBUG] [org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository] Fingerprinting property reports.junitXml.destination (Output) for task ':common:concurrent:testScoverage'
09:00:41.509 [INFO] [org.gradle.api.internal.tasks.execution.ResolveBuildCacheKeyExecuter] Build cache key for task ':common:concurrent:testScoverage' is b869dcd46c4983a587861b0d5f65c3f7
09:00:41.509 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationExecutor] Completing Build operation 'Snapshot task inputs for :common:concurrent:testScoverage'
09:00:41.509 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationExecutor] Build operation 'Snapshot task inputs for :common:concurrent:testScoverage' completed
09:00:41.509 [INFO] [org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter] Caching disabled for task ':common:concurrent:testScoverage': Declares multiple output files for the single output property '$1' via `@OutputFiles`, `@OutputDirectories` or `TaskOutputs.files()`
09:00:41.509 [DEBUG] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Determining if task ':common:concurrent:testScoverage' is up-to-date
09:00:41.509 [INFO] [org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter] Task ':common:concurrent:testScoverage' is not up-to-date because:
  Output property 'binResultsDir' file common/concurrent/build/test-results/testScoverage/binary has been removed.
  Output property 'binResultsDir' file common/concurrent/build/test-results/testScoverage/binary/output.bin has been removed.
  Output property 'binResultsDir' file common/concurrent/build/test-results/testScoverage/binary/output.bin.idx has been removed.
09:00:41.509 [DEBUG] [org.gradle.api.internal.tasks.execution.SkipCachedTaskExecuter] Determining if task ':common:concurrent:testScoverage' is cached already
09:00:41.509 [DEBUG] [org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter] Ensuring parent directory exists for property org.gradle.api.internal.tasks.NonCacheableTaskOutputPropertySpec@4c0c82ab at common/concurrent/build/scoverage/scoverage.measurements.*
09:00:41.509 [DEBUG] [org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter] Ensuring directory exists for property binResultsDir (Output) at common/concurrent/build/test-results/testScoverage/binary
09:00:41.509 [DEBUG] [org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter] Ensuring directory exists for property reports.enabledReports.html.destination (Output) at common/concurrent/build/reports/tests/testScoverage
09:00:41.510 [DEBUG] [org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter] Ensuring directory exists for property reports.enabledReports.junitXml.destination (Output) at common/concurrent/build/test-results/testScoverage
09:00:41.510 [DEBUG] [org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter] Ensuring directory exists for property reports.html.destination (Output) at common/concurrent/build/reports/tests/testScoverage
09:00:41.510 [DEBUG] [org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter] Ensuring directory exists for property reports.junitXml.destination (Output) at common/concurrent/build/test-results/testScoverage
09:00:41.510 [DEBUG] [org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter] Executing actions for task ':common:concurrent:testScoverage'.
09:00:41.510 [DEBUG] [org.gradle.internal.operations.DefaultBuildOperationExecutor] Build operation 'Execute executeTests for :common:concurrent:testScoverage' started

[dsilvasc]

Note that Gradle is removing the restriction on how many output files can be listed for a cacheable task in version 5.0:

https://docs.gradle.org/5.0-rc-2/release-notes.html#plural-task-output-properties-don't-disable-caching-anymore

Plural task output properties don't disable caching anymore
When using @OutputFiles or @OutputDirectories with an Iterable type, Gradle used to disable caching for the task with the following message:

Declares multiple output files for the single output property 'outputFiles' via @OutputFiles, @OutputDirectories or TaskOutputs.files()

This is no longer the case, and using such properties doesn't prevent the task from being cached. The only remaining reason to disable caching for the task is if the output contains file trees.

The log I included in the previous comment was from Gradle 4.10.

[dsilvasc]

Here's the relevant Gradle test case for 4.10:
https://github.com/gradle/gradle/blob/v4.10.0/subprojects/core/src/test/groovy/org/gradle/api/internal/tasks/DefaultTaskOutputsTest.groovy#L443

The test case is gone in 5.0:
https://github.com/gradle/gradle/blob/v5.0.0/subprojects/core/src/test/groovy/org/gradle/api/internal/tasks/DefaultTaskOutputsTest.groovy

And here's the commit changing the behavior in Gradle 5:
gradle/gradle@8895fc8

[dsilvasc]

Not sure if the behavior on Gradle 4.10 is related to this in ScoverageExtension:

            t.tasks[ScoveragePlugin.TEST_NAME].outputs.upToDateWhen { extension.dataDir.listFiles(measurementFile) }

Note also that outputs.upToDateWhen { ... } is tricky and doesn't necessarily re-run tests: https://blog.gradle.org/stop-rerunning-tests

It will only mark the task out-of-date, forcing Gradle to recreate the output. But here’s the thing, if the build cache is enabled, Gradle doesn’t need to run the task to recreate the output. It will find an entry in the cache and unpack the result into the test’s output directory.