HSEARCH-3654 Attempt for reusable mapper replacement

util/internal/test/common/src/main/java/org/hibernate/search/util/impl/test/extension/MultiRunExtension.java

@@ -0,0 +1,233 @@
+/*
+ * Hibernate Search, full-text search for your domain model
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.search.util.impl.test.extension;
+
+import static java.util.Spliterators.spliteratorUnknownSize;
+import static java.util.stream.StreamSupport.stream;
+import static org.junit.platform.commons.util.AnnotationUtils.findRepeatableAnnotations;
+import static org.junit.platform.commons.util.AnnotationUtils.isAnnotated;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Spliterator;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.TestTemplate;
+import org.junit.jupiter.api.extension.AfterEachCallback;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.jupiter.api.extension.Extension;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.api.extension.ParameterContext;
+import org.junit.jupiter.api.extension.ParameterResolutionException;
+import org.junit.jupiter.api.extension.ParameterResolver;
+import org.junit.jupiter.api.extension.TestTemplateInvocationContext;
+import org.junit.jupiter.api.extension.TestTemplateInvocationContextProvider;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.ArgumentsProvider;
+import org.junit.jupiter.params.provider.ArgumentsSource;
+import org.junit.jupiter.params.support.AnnotationConsumerInitializer;
+import org.junit.platform.commons.util.AnnotationUtils;
+import org.junit.platform.commons.util.ReflectionUtils;
+
+import org.opentest4j.AssertionFailedError;
+
+public final class MultiRunExtension
+		implements TestTemplateInvocationContextProvider, AfterEachCallback, ParameterResolver {
+	private List<Object[]> envArguments;
+	private int envIndex = 0;
+	private boolean envInitialized = false;
+	private Method initMethod;
+
+	@Override
+	public boolean supportsParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
+			throws ParameterResolutionException {
+		return true;
+	}
+
+	@Override
+	public Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
+			throws ParameterResolutionException {
+		if ( envArguments == null ) {
+			envArguments = new ArrayList<>();
+			Method testMethod = extensionContext.getRequiredTestMethod();
+
+			for ( ArgumentsSource source : findRepeatableAnnotations( testMethod, ArgumentsSource.class ) ) {
+				ArgumentsProvider argumentsProvider =
+						AnnotationConsumerInitializer.initialize( testMethod, ReflectionUtils.newInstance( source.value() ) );
+				try {
+					envArguments.addAll(
+							argumentsProvider.provideArguments( extensionContext )
+									.map( Arguments::get )
+									.collect( Collectors.toList() ) );
+				}
+				catch (Exception e) {
+					throw new IllegalStateException( "unable to read arguments.", e );
+				}
+			}
+		}
+		return envArguments.get( envIndex )[parameterContext.getIndex()];
+	}
+
+	@Target({ ElementType.METHOD })
+	@Retention(RetentionPolicy.RUNTIME)
+	@TestTemplate
+	@ExtendWith(MultiRunExtension.class)
+	public @interface EnvironmentTest {
+		String init() default "init";
+	}
+
+	@Target({ ElementType.METHOD })
+	@Retention(RetentionPolicy.RUNTIME)
+	public @interface TestToExecute {
+	}
+
+	@Override
+	public boolean supportsTestTemplate(ExtensionContext context) {
+		return isAnnotated( context.getTestMethod(), EnvironmentTest.class );
+	}
+
+	@Override
+	public Stream<TestTemplateInvocationContext> provideTestTemplateInvocationContexts(ExtensionContext context) {
+		EnvironmentTest environment = context.getTestMethod()
+				.flatMap( method -> AnnotationUtils.findAnnotation( method, EnvironmentTest.class ) )
+				.orElseThrow( IllegalStateException::new );
+
+		String init = environment.init();
+		Class<?> testClass = context.getTestClass().orElseThrow();
+		try {
+			initMethod = testClass.getDeclaredMethod( init, context.getRequiredTestMethod().getParameterTypes() );
+			initMethod.setAccessible( true );
+		}
+		catch (NoSuchMethodException e) {
+			throw new IllegalStateException( "Cannot locate init method.", e );
+		}
+
+
+		// find actual "tests" that we'll invoke via reflection:
+		List<Method> testMethods = new ArrayList<>();
+		for ( Method method : testClass.getDeclaredMethods() ) {
+			if ( AnnotationUtils.isAnnotated( method, TestToExecute.class ) ) {
+				testMethods.add( method );
+			}
+		}
+
+		if ( testMethods.isEmpty() ) {
+			throw new IllegalStateException( "No tests to execute were found." );
+		}
+
+		return stream( spliteratorUnknownSize(
+				new Iterator<TestTemplateInvocationContext>() {
+
+					Iterator<Method> test = testMethods.iterator();
+
+					@Override
+					public boolean hasNext() {
+						if ( Boolean.TRUE.equals( read( context, StoreKey.STOP_RUNNING, Boolean.class ) ) ) {
+							return false;
+						}
+						if ( test.hasNext() ) {
+							return true;
+						}
+						else {
+							envIndex++;
+							envInitialized = false;
+						}
+
+						if ( envIndex < envArguments.size() ) {
+							test = testMethods.iterator();
+							return test.hasNext();
+						}
+						return false;
+					}
+
+					@Override
+					public TestTemplateInvocationContext next() {
+						if ( envInitialized ) {
+							Method testMethod = test.next();
+							write( context, StoreKey.TEST_TO_RUN, testMethod );
+
+							return new TestTemplateInvocationContext() {
+
+								@Override
+								public String getDisplayName(int invocationIndex) {
+									return "Env #" + envIndex + ": " + testMethod.getName();
+								}
+
+								@Override
+								public List<Extension> getAdditionalExtensions() {
+									return TestTemplateInvocationContext.super.getAdditionalExtensions();
+								}
+							};
+						}
+						else {
+							return new TestTemplateInvocationContext() {
+
+								@Override
+								public String getDisplayName(int invocationIndex) {
+									return "Env #" + envIndex + ": Initializing";
+								}
+
+								@Override
+								public List<Extension> getAdditionalExtensions() {
+									return TestTemplateInvocationContext.super.getAdditionalExtensions();
+								}
+							};
+						}
+					}
+				}, Spliterator.NONNULL
+		), false );
+	}
+
+	@Override
+	public void afterEach(ExtensionContext extensionContext) throws Exception {
+		// that's where we actually execute the test or init the env
+		if ( envInitialized ) {
+			Method testMethod = read( extensionContext, StoreKey.TEST_TO_RUN, Method.class );
+			testMethod.setAccessible( true );
+			testMethod.invoke( extensionContext.getRequiredTestInstance() );
+		}
+		else {
+			try {
+				initMethod.invoke( extensionContext.getRequiredTestInstance(), envArguments.get( envIndex ) );
+			}
+			catch (Exception e) {
+				envIndex++;
+				if ( envIndex >= envArguments.size() ) {
+					write( extensionContext, StoreKey.STOP_RUNNING, Boolean.TRUE );
+				}
+				throw new AssertionFailedError( "Unable to init the env, stopping further execution", e );
+			}
+			envInitialized = true;
+		}
+	}
+
+	private void write(ExtensionContext context, StoreKey key, Object value) {
+		ExtensionContext.Store store = context.getRoot().getStore(
+				ExtensionContext.Namespace.create( context.getRequiredTestMethod() )
+		);
+		store.put( key, value );
+	}
+
+	private <T> T read(ExtensionContext context, StoreKey key, Class<T> clazz) {
+		ExtensionContext.Store store = context.getRoot().getStore(
+				ExtensionContext.Namespace.create( context.getRequiredTestMethod() )
+		);
+		return store.get( key, clazz );
+	}
+
+	private enum StoreKey {
+		TEST_TO_RUN,
+		STOP_RUNNING
+	}
+}