content: /*
   * 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 org.apache.activemq.artemis.tests.extensions.parameterized;
  
  import static org.apache.activemq.artemis.tests.extensions.parameterized.Parameters.INDEX_TEMPLATE;
  
  import org.junit.jupiter.api.TestTemplate;
  import org.junit.jupiter.api.extension.BeforeEachCallback;
  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.platform.commons.support.AnnotationSupport;
  import org.junit.platform.commons.support.HierarchyTraversalMode;
  
  import java.lang.reflect.Executable;
  import java.lang.reflect.Field;
  import java.lang.reflect.Method;
  import java.text.MessageFormat;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.List;
  import java.util.Objects;
  import java.util.function.Function;
  import java.util.stream.Stream;
  
  /**
   * This extension is used to implement parameterized tests classes for JUnit 5 via the TestTemplate mechanism, replace
   * parameterized test runner from JUnit4 while avoiding the per-method parameterization currently available from Junit
   * 5.
   * <p>
   * When using this extension, all tests must be annotated by {@link TestTemplate}.
   */
  public class ParameterizedTestExtension implements TestTemplateInvocationContextProvider {
  
     private static final ExtensionContext.Namespace NAMESPACE = ExtensionContext.Namespace.create("parameterized");
     private static final String PARAMETERS_STORE_KEY = "parameters";
     private static final String PARAMETER_FIELD_STORE_KEY_PREFIX = "parameterField_";
  
     @Override
     public boolean supportsTestTemplate(ExtensionContext context) {
        return true;
     }
  
     @Override
     public Stream<TestTemplateInvocationContext> provideTestTemplateInvocationContexts(ExtensionContext context) {
        // Search method annotated with @Parameters
        final List<Method> parameterProviders = AnnotationSupport.findAnnotatedMethods(context.getRequiredTestClass(), Parameters.class, HierarchyTraversalMode.TOP_DOWN);
        if (parameterProviders.isEmpty()) {
           throw new IllegalStateException("Cannot find any parameter provider");
        }
  
        if (parameterProviders.size() > 1) {
           throw new IllegalStateException("Multiple parameter providers are found");
        }
  
        Method parameterProvider = parameterProviders.get(0);
        // Get potential test name
        String testNameTemplate = parameterProvider.getAnnotation(Parameters.class).name();
  
        // Get parameter values
        final Object parameterValues;
        try {
           parameterProvider.setAccessible(true);
           parameterValues = parameterProvider.invoke(null);
           context.getStore(NAMESPACE).put(PARAMETERS_STORE_KEY, parameterValues);
        } catch (Exception e) {
           throw new IllegalStateException("Failed to invoke parameter provider", e);
        }
  
        Objects.requireNonNull(parameterValues, "No paramaters returned by @Parameters annotated method: " + parameterProvider.getName());
  
        // Parameter values could be Object[][]
        if (parameterValues instanceof Object[][] typedParameterValues) {
           return createContextForParameters(Arrays.stream(typedParameterValues), testNameTemplate, context);
        }
  
        // or a Collection
        if (parameterValues instanceof Collection<?> typedParameterValues) {
           final Stream<Object[]> parameterValueStream = typedParameterValues.stream()
                 .map((Function<Object, Object[]>) parameterValue -> {
                    if (parameterValue instanceof Object[] objects) {
                       return objects;
                    } else {
                       return new Object[]{parameterValue};
                    }
                 });
           return createContextForParameters(parameterValueStream, testNameTemplate, context);
        }
  
        throw new IllegalStateException(String.format(
              "Return type of @Parameters annotated method \"%s\" should be either Object[][] or Collection",
              parameterProvider));
     }
  
     private static class FieldInjectingInvocationContext implements TestTemplateInvocationContext {
  
        private final String testNameTemplate;
        private final Object[] parameterValues;
  
        FieldInjectingInvocationContext(String testNameTemplate, Object[] parameterValues) {
           this.testNameTemplate = testNameTemplate;
           this.parameterValues = parameterValues;
        }
  
        @Override
        public String getDisplayName(int invocationIndex) {
           return getDisplayNameForTemplate(invocationIndex, testNameTemplate, parameterValues);
        }
  
        @Override
        public List<Extension> getAdditionalExtensions() {
           return Collections.singletonList(new FieldInjectingHook(parameterValues));
        }
  
        private static class FieldInjectingHook implements BeforeEachCallback {
  
           private final Object[] parameterValues;
  
           FieldInjectingHook(Object[] parameterValues) {
              this.parameterValues = parameterValues;
           }
  
           @Override
           public void beforeEach(ExtensionContext context) throws Exception {
              for (int i = 0; i < parameterValues.length; i++) {
                 getParameterField(i, context).setAccessible(true);
                 getParameterField(i, context).set(context.getRequiredTestInstance(), parameterValues[i]);
              }
           }
        }
     }
  
     private static class ConstructorParameterResolverInvocationContext implements TestTemplateInvocationContext {
  
        private final String testNameTemplate;
        private final Object[] parameterValues;
  
        ConstructorParameterResolverInvocationContext(String testNameTemplate, Object[] parameterValues) {
           this.testNameTemplate = testNameTemplate;
           this.parameterValues = parameterValues;
        }
  
        @Override
        public String getDisplayName(int invocationIndex) {
           return getDisplayNameForTemplate(invocationIndex, testNameTemplate, parameterValues);
        }
  
        @Override
        public List<Extension> getAdditionalExtensions() {
           return Collections.singletonList(new ConstructorParameterResolver(parameterValues));
        }
  
        private static class ConstructorParameterResolver implements ParameterResolver {
  
           private final Object[] parameterValues;
  
           ConstructorParameterResolver(Object[] parameterValues) {
              this.parameterValues = parameterValues;
           }
  
           @Override
           public boolean supportsParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
                 throws ParameterResolutionException {
              Executable declaring = parameterContext.getDeclaringExecutable();
              return declaring instanceof java.lang.reflect.Constructor;
           }
  
           @Override
           public Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
                 throws ParameterResolutionException {
              return parameterValues[parameterContext.getIndex()];
           }
        }
     }
  
     private Stream<TestTemplateInvocationContext> createContextForParameters(Stream<Object[]> parameterValueStream,
           String testNameTemplate, ExtensionContext context) {
        // Search fields annotated by @Parameter
        final List<Field> parameterFields = AnnotationSupport.findAnnotatedFields(context.getRequiredTestClass(),
              Parameter.class);
  
        // Use constructor parameter style
        if (parameterFields.isEmpty()) {
           return parameterValueStream.map(
                 parameterValue -> new ConstructorParameterResolverInvocationContext(testNameTemplate, parameterValue));
        }
  
        // Use field injection style
        for (Field parameterField : parameterFields) {
           final int index = parameterField.getAnnotation(Parameter.class).index();
           context.getStore(NAMESPACE).put(getParameterFieldStoreKey(index), parameterField);
        }
        return parameterValueStream
              .map(parameterValue -> new FieldInjectingInvocationContext(testNameTemplate, parameterValue));
     }
  
     private static String getParameterFieldStoreKey(int parameterIndex) {
        return PARAMETER_FIELD_STORE_KEY_PREFIX + parameterIndex;
     }
  
     private static Field getParameterField(int parameterIndex, ExtensionContext context) {
        return (Field) context.getStore(NAMESPACE).get(getParameterFieldStoreKey(parameterIndex));
     }
  
     private static String getDisplayNameForTemplate(int invocationIndex, String template, Object[] parameterValues) {
        if (INDEX_TEMPLATE.equals(template)) {
           return "[" + invocationIndex + "]";
        } else {
           if (template.contains(INDEX_TEMPLATE)) {
              template = template.replace(INDEX_TEMPLATE, "[" + invocationIndex + "]");
           }
  
           return MessageFormat.format(template, parameterValues);
        }
     }
  }
  