Support custom properties file formats in @TestPropertySource

Spring Framework 4.3 introduced the `PropertySourceFactory` SPI for use
with `@PropertySource` on `@Configuration` classes; however, prior to
this commit there was no mechanism to support custom properties file
formats in `@TestPropertySource` for integration tests.

This commit introduces support for configuring a custom
`PropertySourceFactory` via a new `factory` attribute in
`@TestPropertySource` in order to support custom file formats such as
JSON, YAML, etc.

For example, if you create a YamlPropertySourceFactory, you can use it
in integration tests as follows.

@SpringJUnitConfig
@TestPropertySource(locations = "/test.yaml", factory = YamlPropertySourceFactory.class)
class MyTestClass { /* ... /* }

If a custom factory is not specified, traditional `*.properties` and
`*.xml` based `java.util.Properties` file formats are supported, which
was the existing behavior.

Closes gh-30981

spring-test/src/test/java/org/springframework/test/context/MergedContextConfigurationTests.java

@@ -18,6 +18,7 @@ package org.springframework.test.context;
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 
 import org.junit.jupiter.api.Test;
@@ -409,9 +410,9 @@ class MergedContextConfigurationTests {
 	void equalsWithSameContextCustomizers() {
 		Set<ContextCustomizer> customizers = Collections.singleton(mock());
 		MergedContextConfiguration mergedConfig1 = new MergedContextConfiguration(getClass(), EMPTY_STRING_ARRAY,
-			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, null, null, customizers, loader, null, null);
+			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, List.of(), null, customizers, loader, null, null);
 		MergedContextConfiguration mergedConfig2 = new MergedContextConfiguration(getClass(), EMPTY_STRING_ARRAY,
-			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, null, null, customizers, loader, null, null);
+			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, List.of(), null, customizers, loader, null, null);
 		assertThat(mergedConfig2).isEqualTo(mergedConfig1);
 	}
 
@@ -424,9 +425,9 @@ class MergedContextConfigurationTests {
 		Set<ContextCustomizer> customizers2 = Collections.singleton(mock());
 
 		MergedContextConfiguration mergedConfig1 = new MergedContextConfiguration(getClass(), EMPTY_STRING_ARRAY,
-			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, null, null, customizers1, loader, null, null);
+			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, List.of(), null, customizers1, loader, null, null);
 		MergedContextConfiguration mergedConfig2 = new MergedContextConfiguration(getClass(), EMPTY_STRING_ARRAY,
-			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, null, null, customizers2, loader, null, null);
+			EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, List.of(), null, customizers2, loader, null, null);
 		assertThat(mergedConfig2).isNotEqualTo(mergedConfig1);
 		assertThat(mergedConfig1).isNotEqualTo(mergedConfig2);
 	}

spring-test/src/test/java/org/springframework/test/context/env/YamlPropertySourceFactory.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.test.context.env;
+
+import java.util.Properties;
+
+import org.springframework.beans.factory.config.YamlPropertiesFactoryBean;
+import org.springframework.core.env.PropertiesPropertySource;
+import org.springframework.core.env.PropertySource;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.EncodedResource;
+import org.springframework.core.io.support.PropertySourceFactory;
+import org.springframework.util.StringUtils;
+
+/**
+ * Demo {@link PropertySourceFactory} that provides YAML support.
+ *
+ * @author Sam Brannen
+ * @since 6.1
+ */
+class YamlPropertySourceFactory implements PropertySourceFactory {
+
+	@Override
+	public PropertySource<?> createPropertySource(String name, EncodedResource encodedResource) {
+		Resource resource = encodedResource.getResource();
+		if (!StringUtils.hasText(name)) {
+			name = getNameForResource(resource);
+		}
+		YamlPropertiesFactoryBean factoryBean = new YamlPropertiesFactoryBean();
+		factoryBean.setResources(resource);
+		factoryBean.afterPropertiesSet();
+		Properties properties = factoryBean.getObject();
+		return new PropertiesPropertySource(name, properties);
+	}
+
+	/**
+	 * Return the description for the given Resource; if the description is
+	 * empty, return the class name of the resource plus its identity hash code.
+	 */
+	private static String getNameForResource(Resource resource) {
+		String name = resource.getDescription();
+		if (!StringUtils.hasText(name)) {
+			name = resource.getClass().getSimpleName() + "@" + System.identityHashCode(resource);
+		}
+		return name;
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/env/YamlTestProperties.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.test.context.env;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.core.annotation.AliasFor;
+import org.springframework.test.context.TestPropertySource;
+
+/**
+ * @author Sam Brannen
+ * @since 6.1
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@TestPropertySource(factory = YamlPropertySourceFactory.class)
+public @interface YamlTestProperties {
+
+	@AliasFor(annotation = TestPropertySource.class)
+	String[] value();
+
+}

spring-test/src/test/java/org/springframework/test/context/env/YamlTestPropertySourceTests.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.test.context.env;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.io.support.PropertySourceFactory;
+import org.springframework.test.context.TestPropertySource;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration tests for {@link TestPropertySource @TestPropertySource} support
+ * with a custom YAML {@link PropertySourceFactory}.
+ *
+ * @author Sam Brannen
+ * @since 6.1
+ */
+@SpringJUnitConfig
+@YamlTestProperties("test-properties.yaml")
+class YamlTestPropertySourceTests {
+
+	@ParameterizedTest
+	@CsvSource(delimiterString = "->", textBlock = """
+			environments.dev.url   -> https://dev.example.com
+			environments.dev.name  -> 'Developer Setup'
+			environments.prod.url  -> https://prod.example.com
+			environments.prod.name -> 'My Cool App'
+			""")
+	void propertyIsAvailableInEnvironment(String property, String value, @Autowired ConfigurableEnvironment env) {
+		assertThat(env.getProperty(property)).isEqualTo(value);
+	}
+
+
+	@Configuration
+	static class Config {
+		/* no user beans required for these tests */
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/env/repeatable/LocalPropertiesFileAndMetaPropertiesFileTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,15 +16,9 @@
 
 package org.springframework.test.context.env.repeatable;
 
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
 import org.junit.jupiter.api.Test;
 
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.env.repeatable.LocalPropertiesFileAndMetaPropertiesFileTests.MetaFileTestProperty;
 
 /**
  * Integration tests for {@link TestPropertySource @TestPropertySource} as a
@@ -48,15 +42,4 @@ class LocalPropertiesFileAndMetaPropertiesFileTests extends AbstractRepeatableTe
 		assertEnvironmentValue("key2", "meta file");
 	}
 
-
-	/**
-	 * Composed annotation that declares a properties file via
-	 * {@link TestPropertySource @TestPropertySource}.
-	 */
-	@Target(ElementType.TYPE)
-	@Retention(RetentionPolicy.RUNTIME)
-	@TestPropertySource("meta.properties")
-	@interface MetaFileTestProperty {
-	}
-
 }

spring-test/src/test/java/org/springframework/test/context/env/repeatable/LocalYamlFileAndMetaPropertiesFileTests.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.test.context.env.repeatable;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.test.context.env.YamlTestProperties;
+
+/**
+ * Analogous to {@link LocalPropertiesFileAndMetaPropertiesFileTests} except
+ * that the local file is YAML.
+ *
+ * @author Sam Brannen
+ * @since 6.1
+ */
+@YamlTestProperties("local.yaml")
+@MetaFileTestProperty
+class LocalYamlFileAndMetaPropertiesFileTests extends AbstractRepeatableTestPropertySourceTests {
+
+	@Test
+	void test() {
+		assertEnvironmentValue("key1", "local file");
+		assertEnvironmentValue("key2", "meta file");
+
+		assertEnvironmentValue("environments.dev.url", "https://dev.example.com");
+		assertEnvironmentValue("environments.dev.name", "Developer Setup");
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/env/repeatable/MetaFileTestProperty.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.test.context.env.repeatable;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.test.context.TestPropertySource;
+
+/**
+ * Composed annotation that declares a properties file via
+ * {@link TestPropertySource @TestPropertySource}.
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@TestPropertySource("meta.properties")
+@interface MetaFileTestProperty {
+}

spring-test/src/test/java/org/springframework/test/context/support/BootstrapTestUtilsMergedConfigTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -187,6 +187,7 @@ class BootstrapTestUtilsMergedConfigTests extends AbstractContextConfigurationUt
 		assertMergedConfigForLocationPaths(RelativeFooXmlLocation.class);
 	}
 
+	@SuppressWarnings("deprecation")
 	private void assertMergedConfigForLocationPaths(Class<?> testClass) {
 		MergedContextConfiguration mergedConfig = buildMergedContextConfiguration(testClass);
 

spring-test/src/test/java/org/springframework/test/context/support/TestPropertySourceUtilsTests.java

@@ -18,7 +18,9 @@ package org.springframework.test.context.support;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.util.List;
 import java.util.Map;
+import java.util.stream.Stream;
 
 import org.assertj.core.api.SoftAssertions;
 import org.junit.jupiter.api.Test;
@@ -29,6 +31,7 @@ import org.springframework.core.env.ConfigurableEnvironment;
 import org.springframework.core.env.MutablePropertySources;
 import org.springframework.core.io.ByteArrayResource;
 import org.springframework.core.io.ResourceLoader;
+import org.springframework.core.io.support.PropertySourceDescriptor;
 import org.springframework.mock.env.MockEnvironment;
 import org.springframework.mock.env.MockPropertySource;
 import org.springframework.test.context.TestPropertySource;
@@ -295,7 +298,9 @@ class TestPropertySourceUtilsTests {
 		MergedTestPropertySources mergedPropertySources = buildMergedTestPropertySources(testClass);
 		SoftAssertions.assertSoftly(softly -> {
 			softly.assertThat(mergedPropertySources).isNotNull();
-			softly.assertThat(mergedPropertySources.getLocations()).isEqualTo(expectedLocations);
+			Stream<String> locations = mergedPropertySources.getPropertySourceDescriptors().stream()
+					.map(PropertySourceDescriptor::locations).flatMap(List::stream);
+			softly.assertThat(locations).containsExactly(expectedLocations);
 			softly.assertThat(mergedPropertySources.getProperties()).isEqualTo(expectedProperties);
 		});
 	}

spring-test/src/test/java/org/springframework/test/context/web/AnnotationConfigWebContextLoaderTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,14 +33,15 @@ class AnnotationConfigWebContextLoaderTests {
 
 
 	@Test
-	void configMustNotContainLocations() throws Exception {
+	@SuppressWarnings("deprecation")
+	void configMustNotContainLocations() {
 		AnnotationConfigWebContextLoader loader = new AnnotationConfigWebContextLoader();
 		WebMergedContextConfiguration mergedConfig = new WebMergedContextConfiguration(getClass(),
 				new String[] { "config.xml" }, EMPTY_CLASS_ARRAY, null, EMPTY_STRING_ARRAY, EMPTY_STRING_ARRAY,
 				EMPTY_STRING_ARRAY, "resource/path", loader, null, null);
 		assertThatIllegalStateException()
-			.isThrownBy(() -> loader.loadContext(mergedConfig))
-			.withMessageContaining("does not support resource locations");
+				.isThrownBy(() -> loader.loadContext(mergedConfig))
+				.withMessageContaining("does not support resource locations");
 	}
 
 }

spring-test/src/test/java/org/springframework/test/context/web/GenericXmlWebContextLoaderTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -34,12 +34,13 @@ class GenericXmlWebContextLoaderTests {
 	@Test
 	void configMustNotContainAnnotatedClasses() throws Exception {
 		GenericXmlWebContextLoader loader = new GenericXmlWebContextLoader();
+		@SuppressWarnings("deprecation")
 		WebMergedContextConfiguration mergedConfig = new WebMergedContextConfiguration(getClass(), EMPTY_STRING_ARRAY,
 				new Class<?>[] { getClass() }, null, EMPTY_STRING_ARRAY, EMPTY_STRING_ARRAY, EMPTY_STRING_ARRAY,
 				"resource/path", loader, null, null);
 		assertThatIllegalStateException()
-			.isThrownBy(() -> loader.loadContext(mergedConfig))
-			.withMessageContaining("does not support annotated classes");
+				.isThrownBy(() -> loader.loadContext(mergedConfig))
+				.withMessageContaining("does not support annotated classes");
 	}
 
 }