Revert "Introduce configuration parameter for opting in to new implementation"

This reverts commit 9d77839.

Author: marcphilipp

documentation/src/test/resources/junit-platform.properties

@@ -1,5 +1,4 @@
 junit.jupiter.execution.parallel.enabled=true
-junit.jupiter.execution.parallel.executor=org.junit.platform.engine.support.hierarchical.ConcurrentHierarchicalTestExecutorService
 junit.jupiter.execution.parallel.mode.default=concurrent
 junit.jupiter.execution.parallel.config.strategy=fixed
 junit.jupiter.execution.parallel.config.fixed.parallelism=6

junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/Constants.java

@@ -13,7 +13,6 @@
 import static org.apiguardian.api.API.Status.EXPERIMENTAL;
 import static org.apiguardian.api.API.Status.MAINTAINED;
 import static org.apiguardian.api.API.Status.STABLE;
-import static org.junit.jupiter.engine.config.JupiterConfiguration.PARALLEL_CONFIG_PREFIX;
 import static org.junit.platform.engine.support.hierarchical.DefaultParallelExecutionConfigurationStrategy.CONFIG_CUSTOM_CLASS_PROPERTY_NAME;
 import static org.junit.platform.engine.support.hierarchical.DefaultParallelExecutionConfigurationStrategy.CONFIG_DYNAMIC_FACTOR_PROPERTY_NAME;
 import static org.junit.platform.engine.support.hierarchical.DefaultParallelExecutionConfigurationStrategy.CONFIG_FIXED_MAX_POOL_SIZE_PROPERTY_NAME;
@@ -39,8 +38,6 @@
 import org.junit.jupiter.api.parallel.Execution;
 import org.junit.jupiter.engine.config.JupiterConfiguration;
 import org.junit.platform.commons.util.ClassNamePatternFilterUtils;
-import org.junit.platform.engine.support.hierarchical.ForkJoinPoolHierarchicalTestExecutorService;
-import org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutorService;
 import org.junit.platform.engine.support.hierarchical.ParallelExecutionConfigurationStrategy;
 
 /**
@@ -213,21 +210,6 @@ public final class Constants {
 	@API(status = STABLE, since = "5.10")
 	public static final String PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME = JupiterConfiguration.PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME;
 
-	/**
-	 * Property name used to configure the fully qualified class name
-	 * {@link HierarchicalTestExecutorService} implementation to use if parallel
-	 * test execution is
-	 * {@linkplain #PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME enabled}: {@value}
-	 *
-	 * <p>The implementation class must provide a parameter of type
-	 *
-	 * <p>By default, {@link ForkJoinPoolHierarchicalTestExecutorService} is used.
-	 *
-	 * @since 6.1
-	 */
-	@API(status = EXPERIMENTAL, since = "6.1")
-	public static final String PARALLEL_EXECUTION_EXECUTOR_PROPERTY_NAME = JupiterConfiguration.PARALLEL_EXECUTION_EXECUTOR_PROPERTY_NAME;
-
 	/**
 	 * Property name used to enable auto-closing of {@link AutoCloseable} instances
 	 *
@@ -255,6 +237,8 @@ public final class Constants {
 	@API(status = STABLE, since = "5.10")
 	public static final String DEFAULT_CLASSES_EXECUTION_MODE_PROPERTY_NAME = Execution.DEFAULT_CLASSES_EXECUTION_MODE_PROPERTY_NAME;
 
+	static final String PARALLEL_CONFIG_PREFIX = "junit.jupiter.execution.parallel.config.";
+
 	/**
 	 * Property name used to select the
 	 * {@link ParallelExecutionConfigurationStrategy}: {@value}

junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/JupiterTestEngine.java

@@ -27,7 +27,9 @@
 import org.junit.platform.engine.ExecutionRequest;
 import org.junit.platform.engine.TestDescriptor;
 import org.junit.platform.engine.UniqueId;
+import org.junit.platform.engine.support.config.PrefixedConfigurationParameters;
 import org.junit.platform.engine.support.discovery.DiscoveryIssueReporter;
+import org.junit.platform.engine.support.hierarchical.ConcurrentHierarchicalTestExecutorService;
 import org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine;
 import org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutorService;
 import org.junit.platform.engine.support.hierarchical.ThrowableCollector;
@@ -77,7 +79,8 @@ public TestDescriptor discover(EngineDiscoveryRequest discoveryRequest, UniqueId
 	protected HierarchicalTestExecutorService createExecutorService(ExecutionRequest request) {
 		JupiterConfiguration configuration = getJupiterConfiguration(request);
 		if (configuration.isParallelExecutionEnabled()) {
-			return configuration.createParallelExecutorService();
+			return new ConcurrentHierarchicalTestExecutorService(new PrefixedConfigurationParameters(
+				request.getConfigurationParameters(), Constants.PARALLEL_CONFIG_PREFIX));
 		}
 		return super.createExecutorService(request);
 	}

junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/config/CachingJupiterConfiguration.java

@@ -32,7 +32,6 @@
 import org.junit.jupiter.api.io.TempDirFactory;
 import org.junit.jupiter.api.parallel.ExecutionMode;
 import org.junit.platform.engine.OutputDirectoryCreator;
-import org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutorService;
 
 /**
  * Caching implementation of the {@link JupiterConfiguration} API.
@@ -70,11 +69,6 @@ public boolean isParallelExecutionEnabled() {
 			__ -> delegate.isParallelExecutionEnabled());
 	}
 
-	@Override
-	public HierarchicalTestExecutorService createParallelExecutorService() {
-		return delegate.createParallelExecutorService();
-	}
-
 	@Override
 	public boolean isClosingStoredAutoCloseablesEnabled() {
 		return (boolean) cache.computeIfAbsent(CLOSING_STORED_AUTO_CLOSEABLE_ENABLED_PROPERTY_NAME,

junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/config/DefaultJupiterConfiguration.java

@@ -34,17 +34,13 @@
 import org.junit.jupiter.api.io.CleanupMode;
 import org.junit.jupiter.api.io.TempDirFactory;
 import org.junit.jupiter.api.parallel.ExecutionMode;
-import org.junit.jupiter.engine.config.InstantiatingConfigurationParameterConverter.Strictness;
 import org.junit.platform.commons.util.ClassNamePatternFilterUtils;
 import org.junit.platform.commons.util.Preconditions;
 import org.junit.platform.engine.ConfigurationParameters;
 import org.junit.platform.engine.DiscoveryIssue;
 import org.junit.platform.engine.DiscoveryIssue.Severity;
 import org.junit.platform.engine.OutputDirectoryCreator;
-import org.junit.platform.engine.support.config.PrefixedConfigurationParameters;
 import org.junit.platform.engine.support.discovery.DiscoveryIssueReporter;
-import org.junit.platform.engine.support.hierarchical.ForkJoinPoolHierarchicalTestExecutorService;
-import org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutorService;
 
 /**
  * Default implementation of the {@link JupiterConfiguration} API.
@@ -85,10 +81,6 @@ public class DefaultJupiterConfiguration implements JupiterConfiguration {
 	private static final ConfigurationParameterConverter<ExtensionContextScope> extensionContextScopeConverter = //
 		new EnumConfigurationParameterConverter<>(ExtensionContextScope.class, "extension context scope");
 
-	private static final ConfigurationParameterConverter<HierarchicalTestExecutorService> parallelExecutorServiceConverter = //
-		new InstantiatingConfigurationParameterConverter<>(HierarchicalTestExecutorService.class,
-			"parallel executor service", Strictness.FAIL, parameters -> new Object[] { parallelConfig(parameters) });
-
 	private final ConfigurationParameters configurationParameters;
 	private final OutputDirectoryCreator outputDirectoryCreator;
 
@@ -144,13 +136,6 @@ public boolean isParallelExecutionEnabled() {
 		return configurationParameters.getBoolean(PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME).orElse(false);
 	}
 
-	@Override
-	public HierarchicalTestExecutorService createParallelExecutorService() {
-		return parallelExecutorServiceConverter.get(configurationParameters, PARALLEL_EXECUTION_EXECUTOR_PROPERTY_NAME) //
-				.orElseGet(
-					() -> new ForkJoinPoolHierarchicalTestExecutorService(parallelConfig(configurationParameters)));
-	}
-
 	@Override
 	public boolean isClosingStoredAutoCloseablesEnabled() {
 		return configurationParameters.getBoolean(CLOSING_STORED_AUTO_CLOSEABLE_ENABLED_PROPERTY_NAME).orElse(true);
@@ -229,9 +214,4 @@ public ExtensionContextScope getDefaultTestInstantiationExtensionContextScope()
 	public OutputDirectoryCreator getOutputDirectoryCreator() {
 		return outputDirectoryCreator;
 	}
-
-	private static PrefixedConfigurationParameters parallelConfig(ConfigurationParameters configurationParameters) {
-		return new PrefixedConfigurationParameters(configurationParameters, PARALLEL_CONFIG_PREFIX);
-	}
-
 }

junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/config/InstantiatingConfigurationParameterConverter.java

@@ -10,43 +10,28 @@
 
 package org.junit.jupiter.engine.config;
 
-import java.lang.reflect.Constructor;
 import java.util.Optional;
-import java.util.function.Function;
 import java.util.function.Supplier;
-import java.util.stream.IntStream;
 
-import org.junit.platform.commons.JUnitException;
 import org.junit.platform.commons.function.Try;
 import org.junit.platform.commons.logging.Logger;
 import org.junit.platform.commons.logging.LoggerFactory;
 import org.junit.platform.commons.support.ReflectionSupport;
-import org.junit.platform.commons.util.Preconditions;
-import org.junit.platform.commons.util.ReflectionUtils;
 import org.junit.platform.engine.ConfigurationParameters;
 
 /**
  * @since 5.5
  */
-final class InstantiatingConfigurationParameterConverter<T> implements ConfigurationParameterConverter<T> {
+class InstantiatingConfigurationParameterConverter<T> implements ConfigurationParameterConverter<T> {
 
 	private static final Logger logger = LoggerFactory.getLogger(InstantiatingConfigurationParameterConverter.class);
 
 	private final Class<T> clazz;
 	private final String name;
-	private final Strictness strictness;
-	private final Function<ConfigurationParameters, Object[]> argumentResolver;
 
 	InstantiatingConfigurationParameterConverter(Class<T> clazz, String name) {
-		this(clazz, name, Strictness.WARN, __ -> new Object[0]);
-	}
-
-	InstantiatingConfigurationParameterConverter(Class<T> clazz, String name, Strictness strictness,
-			Function<ConfigurationParameters, Object[]> argumentResolver) {
 		this.clazz = clazz;
 		this.name = name;
-		this.strictness = strictness;
-		this.argumentResolver = argumentResolver;
 	}
 
 	@Override
@@ -59,62 +44,31 @@ Supplier<Optional<T>> supply(ConfigurationParameters configurationParameters, St
 		return configurationParameters.get(key)
 				.map(String::strip)
 				.filter(className -> !className.isEmpty())
-				.map(className -> newInstanceSupplier(className, key, configurationParameters))
+				.map(className -> newInstanceSupplier(className, key))
 				.orElse(Optional::empty);
 		// @formatter:on
 	}
 
-	private Supplier<Optional<T>> newInstanceSupplier(String className, String key,
-			ConfigurationParameters configurationParameters) {
+	private Supplier<Optional<T>> newInstanceSupplier(String className, String key) {
 		Try<Class<?>> clazz = ReflectionSupport.tryToLoadClass(className);
 		// @formatter:off
-		return () -> clazz.andThenTry(it -> instantiate(it, configurationParameters))
+		return () -> clazz.andThenTry(ReflectionSupport::newInstance)
 				.andThenTry(this.clazz::cast)
 				.ifSuccess(generator -> logSuccessMessage(className, key))
 				.ifFailure(cause -> logFailureMessage(className, key, cause))
 				.toOptional();
 		// @formatter:on
 	}
 
-	@SuppressWarnings("unchecked")
-	private <V> V instantiate(Class<V> clazz, ConfigurationParameters configurationParameters) {
-		var arguments = argumentResolver.apply(configurationParameters);
-		if (arguments.length == 0) {
-			return ReflectionSupport.newInstance(clazz);
-		}
-		var constructors = ReflectionUtils.findConstructors(clazz, it -> {
-			if (it.getParameterCount() != arguments.length) {
-				return false;
-			}
-			var parameters = it.getParameters();
-			return IntStream.range(0, parameters.length) //
-					.allMatch(i -> parameters[i].getType().isAssignableFrom(arguments[i].getClass()));
-		});
-		Preconditions.condition(constructors.size() == 1,
-			() -> "Failed to find unambiguous constructor for %s. Candidates: %s".formatted(clazz.getName(),
-				constructors));
-		return ReflectionUtils.newInstance((Constructor<V>) constructors.get(0), arguments);
-	}
-
 	private void logFailureMessage(String className, String key, Exception cause) {
-		switch (strictness) {
-			case WARN -> logger.warn(cause, () -> """
-					Failed to load default %s class '%s' set via the '%s' configuration parameter. \
-					Falling back to default behavior.""".formatted(this.name, className, key));
-			case FAIL -> throw new JUnitException(
-				"Failed to load default %s class '%s' set via the '%s' configuration parameter.".formatted(this.name,
-					className, key),
-				cause);
-		}
+		logger.warn(cause, () -> """
+				Failed to load default %s class '%s' set via the '%s' configuration parameter. \
+				Falling back to default behavior.""".formatted(this.name, className, key));
 	}
 
 	private void logSuccessMessage(String className, String key) {
 		logger.config(() -> "Using default %s '%s' set via the '%s' configuration parameter.".formatted(this.name,
 			className, key));
 	}
 
-	enum Strictness {
-		FAIL, WARN
-	}
-
 }

junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/config/JupiterConfiguration.java

@@ -31,7 +31,6 @@
 import org.junit.jupiter.api.parallel.Execution;
 import org.junit.jupiter.api.parallel.ExecutionMode;
 import org.junit.platform.engine.OutputDirectoryCreator;
-import org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutorService;
 
 /**
  * @since 5.4
@@ -43,8 +42,6 @@ public interface JupiterConfiguration {
 	String EXTENSIONS_AUTODETECTION_EXCLUDE_PROPERTY_NAME = "junit.jupiter.extensions.autodetection.exclude";
 	String DEACTIVATE_CONDITIONS_PATTERN_PROPERTY_NAME = "junit.jupiter.conditions.deactivate";
 	String PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME = "junit.jupiter.execution.parallel.enabled";
-	String PARALLEL_EXECUTION_EXECUTOR_PROPERTY_NAME = "junit.jupiter.execution.parallel.executor";
-	String PARALLEL_CONFIG_PREFIX = "junit.jupiter.execution.parallel.config.";
 	String CLOSING_STORED_AUTO_CLOSEABLE_ENABLED_PROPERTY_NAME = "junit.jupiter.extensions.store.close.autocloseable.enabled";
 	String DEFAULT_EXECUTION_MODE_PROPERTY_NAME = Execution.DEFAULT_EXECUTION_MODE_PROPERTY_NAME;
 	String DEFAULT_CLASSES_EXECUTION_MODE_PROPERTY_NAME = Execution.DEFAULT_CLASSES_EXECUTION_MODE_PROPERTY_NAME;
@@ -64,8 +61,6 @@ public interface JupiterConfiguration {
 
 	boolean isParallelExecutionEnabled();
 
-	HierarchicalTestExecutorService createParallelExecutorService();
-
 	boolean isClosingStoredAutoCloseablesEnabled();
 
 	boolean isExtensionAutoDetectionEnabled();

platform-tests/src/test/java/org/junit/platform/engine/support/hierarchical/ParallelExecutionIntegrationTests.java

@@ -25,7 +25,6 @@
 import static org.junit.jupiter.engine.Constants.PARALLEL_CONFIG_FIXED_PARALLELISM_PROPERTY_NAME;
 import static org.junit.jupiter.engine.Constants.PARALLEL_CONFIG_STRATEGY_PROPERTY_NAME;
 import static org.junit.jupiter.engine.Constants.PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME;
-import static org.junit.jupiter.engine.Constants.PARALLEL_EXECUTION_EXECUTOR_PROPERTY_NAME;
 import static org.junit.platform.commons.util.CollectionUtils.getOnlyElement;
 import static org.junit.platform.engine.discovery.DiscoverySelectors.selectClasses;
 import static org.junit.platform.engine.discovery.DiscoverySelectors.selectMethod;
@@ -75,7 +74,6 @@
 import org.junit.jupiter.api.parallel.Execution;
 import org.junit.jupiter.api.parallel.Isolated;
 import org.junit.jupiter.api.parallel.ResourceLock;
-import org.junit.jupiter.params.ParameterizedClass;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 import org.junit.platform.engine.DiscoverySelector;
@@ -91,10 +89,7 @@
  * @since 1.3
  */
 @SuppressWarnings({ "JUnitMalformedDeclaration", "NewClassNamingConvention" })
-@ParameterizedClass
-@ValueSource(classes = { ForkJoinPoolHierarchicalTestExecutorService.class,
-		ConcurrentHierarchicalTestExecutorService.class })
-record ParallelExecutionIntegrationTests(Class<? extends HierarchicalTestExecutorService> implementation) {
+class ParallelExecutionIntegrationTests {
 
 	@Test
 	void successfulParallelTest(TestReporter reporter) {
@@ -584,12 +579,11 @@ private EngineExecutionResults executeWithFixedParallelism(int parallelism, Map<
 		return executeWithFixedParallelism(parallelism, configParams, selectClasses(testClasses));
 	}
 
-	private EngineExecutionResults executeWithFixedParallelism(int parallelism, Map<String, String> configParams,
+	private static EngineExecutionResults executeWithFixedParallelism(int parallelism, Map<String, String> configParams,
 			List<? extends DiscoverySelector> selectors) {
 		return EngineTestKit.engine("junit-jupiter") //
 				.selectors(selectors) //
 				.configurationParameter(PARALLEL_EXECUTION_ENABLED_PROPERTY_NAME, String.valueOf(true)) //
-				.configurationParameter(PARALLEL_EXECUTION_EXECUTOR_PROPERTY_NAME, implementation.getName()) //
 				.configurationParameter(PARALLEL_CONFIG_STRATEGY_PROPERTY_NAME, "fixed") //
 				.configurationParameter(PARALLEL_CONFIG_FIXED_PARALLELISM_PROPERTY_NAME, String.valueOf(parallelism)) //
 				.configurationParameters(configParams) //

platform-tooling-support-tests/src/test/resources/junit-platform.properties

@@ -1,5 +1,4 @@
 junit.jupiter.execution.parallel.enabled=true
-junit.jupiter.execution.parallel.executor=org.junit.platform.engine.support.hierarchical.ConcurrentHierarchicalTestExecutorService
 junit.jupiter.execution.parallel.mode.default=concurrent
 junit.jupiter.execution.parallel.config.strategy=dynamic
 junit.jupiter.execution.parallel.config.dynamic.factor=0.25