Add support for working with resources in tests

Closes gh-44444

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/OnClassWithPackageResourcesTests.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithPackageResources} on a class.
+ *
+ * @author Andy Wilkinson
+ */
+@WithPackageResources({ "resource-1.txt", "resource-2.txt", "sub/resource-3.txt" })
+class OnClassWithPackageResourcesTests {
+
+	@Test
+	void whenWithPackageResourcesIsUsedOnAClassThenResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("resource-1.txt").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("one");
+		assertThat(new ClassPathResource("resource-2.txt").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("two");
+		assertThat(new ClassPathResource("sub/resource-3.txt").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("three");
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/OnClassWithResourceTests.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithResource} when used on a class.
+ *
+ * @author Andy Wilkinson
+ */
+@WithResource(name = "on-class", content = "class content")
+class OnClassWithResourceTests {
+
+	@Test
+	void whenWithResourceIsUsedOnAClassThenResourceIsAvailable() throws IOException {
+		assertThat(new ClassPathResource("on-class").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("class content");
+	}
+
+	@Test
+	@WithResource(name = "method-resource", content = "method")
+	void whenWithResourceIsUsedOnClassAndMethodThenBothResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("on-class").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("class content");
+		assertThat(new ClassPathResource("method-resource").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("method");
+	}
+
+	@Test
+	@WithResource(name = "method-resource-1", content = "method-1")
+	@WithResource(name = "method-resource-2", content = "method-2")
+	void whenWithResourceIsUsedOnClassAndRepeatedOnMethodThenAllResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("on-class").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("class content");
+		assertThat(new ClassPathResource("method-resource-1").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("method-1");
+		assertThat(new ClassPathResource("method-resource-2").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("method-2");
+	}
+
+	@Nested
+	class NestedTests {
+
+		@Test
+		void whenWithResourceIsUsedOnEnclosingClassThenResourceIsAvailable() throws IOException {
+			assertThat(new ClassPathResource("on-class").getContentAsString(StandardCharsets.UTF_8))
+				.isEqualTo("class content");
+		}
+
+	}
+
+	@Nested
+	@WithResource(name = "on-nested-class", content = "nested class content")
+	class WithResourceNestedTests {
+
+		@Test
+		void whenWithResourceIsUsedOnEnclosingClassAndClassThenBothResourcesAreAvailable() throws IOException {
+			assertThat(new ClassPathResource("on-class").getContentAsString(StandardCharsets.UTF_8))
+				.isEqualTo("class content");
+			assertThat(new ClassPathResource("on-nested-class").getContentAsString(StandardCharsets.UTF_8))
+				.isEqualTo("nested class content");
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/OnSuperClassWithPackageResourcesTests.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithPackageResources} when used on a super-class.
+ *
+ * @author Andy Wilkinson
+ */
+class OnSuperClassWithPackageResourcesTests extends WithPackageResourcesClass {
+
+	@Test
+	void whenWithPackageResourcesIsUsedOnASuperClassThenResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("resource-1.txt").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("one");
+		assertThat(new ClassPathResource("resource-2.txt").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("two");
+		assertThat(new ClassPathResource("sub/resource-3.txt").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("three");
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/OnSuperClassWithResourceTests.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithResource} when used on a super-class.
+ *
+ * @author Andy Wilkinson
+ */
+class OnSuperClassWithResourceTests extends WithResourceClass {
+
+	@Test
+	void whenWithResourceIsUsedOnASuperClassThenResourceIsAvailable() throws IOException {
+		assertThat(new ClassPathResource("on-super-class").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("super-class content");
+	}
+
+	@Test
+	@WithResource(name = "method-resource", content = "method")
+	void whenWithResourceIsUsedOnASuperClassAndMethodThenBothResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("on-super-class").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("super-class content");
+		assertThat(new ClassPathResource("method-resource").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("method");
+	}
+
+	@Test
+	@WithResource(name = "method-resource-1", content = "method-1")
+	@WithResource(name = "method-resource-2", content = "method-2")
+	void whenWithResourceIsUsedOnASuperClassAndRepeatedOnMethodThenAllResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("on-super-class").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("super-class content");
+		assertThat(new ClassPathResource("method-resource-1").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("method-1");
+		assertThat(new ClassPathResource("method-resource-2").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("method-2");
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/ResourcesTests.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.nio.file.Path;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
+
+/**
+ * Tests for {@link Resources}.
+ *
+ * @author Andy Wilkinson
+ */
+class ResourcesTests {
+
+	@TempDir
+	private Path root;
+
+	@Test
+	void whenAddResourceThenResourceIsCreated() {
+		new Resources(this.root).addResource("test", "test-content");
+		assertThat(this.root.resolve("test")).hasContent("test-content");
+	}
+
+	@Test
+	void whenAddResourceHasContentReferencingResourceRootThenResourceIsCreatedWithReferenceToRoot() {
+		new Resources(this.root).addResource("test", "*** ${resourceRoot} ***");
+		assertThat(this.root.resolve("test")).hasContent("*** " + this.root + " ***");
+	}
+
+	@Test
+	void whenAddResourceWithPathThenResourceIsCreated() {
+		new Resources(this.root).addResource("a/b/c/test", "test-content");
+		assertThat(this.root.resolve("a/b/c/test")).hasContent("test-content");
+	}
+
+	@Test
+	void whenAddResourceAndResourceAlreadyExistsThenResourcesIsOverwritten() {
+		Resources resources = new Resources(this.root);
+		resources.addResource("a/b/c/test", "original-content");
+		resources.addResource("a/b/c/test", "new-content");
+		assertThat(this.root.resolve("a/b/c/test")).hasContent("new-content");
+	}
+
+	@Test
+	void whenAddPackageThenNamedResourcesFromPackageAreCreated() {
+		new Resources(this.root).addPackage(getClass().getPackage(),
+				new String[] { "resource-1.txt", "sub/resource-3.txt" });
+		assertThat(this.root.resolve("resource-1.txt")).hasContent("one");
+		assertThat(this.root.resolve("resource-2.txt")).doesNotExist();
+		assertThat(this.root.resolve("sub/resource-3.txt")).hasContent("three");
+	}
+
+	@Test
+	void whenAddResourceAndDeleteThenResourceDoesNotExist() {
+		Resources resources = new Resources(this.root);
+		resources.addResource("test", "test-content");
+		assertThat(this.root.resolve("test")).hasContent("test-content");
+		resources.delete();
+		assertThat(this.root.resolve("test")).doesNotExist();
+	}
+
+	@Test
+	void whenAddPackageAndDeleteThenResourcesDoNotExist() {
+		Resources resources = new Resources(this.root);
+		resources.addPackage(getClass().getPackage(),
+				new String[] { "resource-1.txt", "resource-2.txt", "sub/resource-3.txt" });
+		assertThat(this.root.resolve("resource-1.txt")).hasContent("one");
+		assertThat(this.root.resolve("resource-2.txt")).hasContent("two");
+		assertThat(this.root.resolve("sub/resource-3.txt")).hasContent("three");
+		resources.delete();
+		assertThat(this.root.resolve("resource-1.txt")).doesNotExist();
+		assertThat(this.root.resolve("resource-2.txt")).doesNotExist();
+		assertThat(this.root.resolve("sub/resource-3.txt")).doesNotExist();
+		assertThat(this.root.resolve("sub")).doesNotExist();
+	}
+
+	@Test
+	void whenAddDirectoryThenDirectoryIsCreated() {
+		Resources resources = new Resources(this.root);
+		resources.addDirectory("dir");
+		assertThat(this.root.resolve("dir")).isDirectory();
+	}
+
+	@Test
+	void whenAddDirectoryWithPathThenDirectoryIsCreated() {
+		Resources resources = new Resources(this.root);
+		resources.addDirectory("one/two/three/dir");
+		assertThat(this.root.resolve("one/two/three/dir")).isDirectory();
+	}
+
+	@Test
+	void whenAddDirectoryAndDirectoryAlreadyExistsThenDoesNotThrow() {
+		Resources resources = new Resources(this.root);
+		resources.addDirectory("one/two/three/dir");
+		resources.addDirectory("one/two/three/dir");
+		assertThat(this.root.resolve("one/two/three/dir")).isDirectory();
+	}
+
+	@Test
+	void whenAddDirectoryAndResourceAlreadyExistsThenIllegalStateExceptionIsThrown() {
+		Resources resources = new Resources(this.root);
+		resources.addResource("one/two/three/", "content");
+		assertThatIllegalStateException().isThrownBy(() -> resources.addDirectory("one/two/three"));
+	}
+
+	@Test
+	void whenAddResourceAndDirectoryAlreadyExistsThenIllegalStateExceptionIsThrown() {
+		Resources resources = new Resources(this.root);
+		resources.addDirectory("one/two/three");
+		assertThatIllegalStateException().isThrownBy(() -> resources.addResource("one/two/three", "content"));
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/WithPackageResourcesClass.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+/**
+ * Class to test the use of {@link WithPackageResources} on a super-class.
+ *
+ * @author Andy Wilkinson
+ */
+@WithPackageResources({ "resource-1.txt", "resource-2.txt", "sub/resource-3.txt" })
+class WithPackageResourcesClass {
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/WithPackageResourcesTests.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithPackageResources}.
+ *
+ * @author Andy Wilkinson
+ */
+class WithPackageResourcesTests {
+
+	@Test
+	@WithPackageResources({ "resource-1.txt", "resource-2.txt", "sub/resource-3.txt" })
+	void whenWithPackageResourcesIsUsedOnAMethodThenResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("resource-1.txt").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("one");
+		assertThat(new ClassPathResource("resource-2.txt").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("two");
+		assertThat(new ClassPathResource("sub/resource-3.txt").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("three");
+	}
+
+	@Test
+	@WithPackageResources("sub/resource-3.txt")
+	void whenWithPackageResourcesOnlyIncludesSomeResourcesThenOnlyIncludedResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("resource-1.txt").exists()).isFalse();
+		assertThat(new ClassPathResource("resource-2.txt").exists()).isFalse();
+		assertThat(new ClassPathResource("sub/resource-3.txt").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("three");
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/WithResourceClass.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+/**
+ * Class to test the use of {@link WithResource} on a super-class
+ *
+ * @author Andy Wilkinson
+ */
+@WithResource(name = "on-super-class", content = "super-class content")
+class WithResourceClass {
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/WithResourceDirectoryTests.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithResourceDirectory}.
+ *
+ * @author Andy Wilkinson
+ */
+class WithResourceDirectoryTests {
+
+	@Test
+	@WithResourceDirectory("test")
+	void whenWithResourceDirectoryIsUsedOnAMethodThenDirectoryIsCreated() throws IOException {
+		assertThat(new ClassPathResource("test").getFile()).isDirectory();
+	}
+
+	@Test
+	@WithResourceDirectory("com/example/nested")
+	void whenWithResourceDirectoryNamesANestedDirectoryThenDirectoryIsCreated() throws IOException {
+		assertThat(new ClassPathResource("com/example/nested").getFile()).isDirectory();
+	}
+
+	@Test
+	@WithResourceDirectory("1")
+	@WithResourceDirectory("2")
+	@WithResourceDirectory("3")
+	void whenWithResourceDirectoryIsRepeatedOnAMethodThenAllResourceDirectoriesAreCreated() throws IOException {
+		assertThat(new ClassPathResource("1").getFile()).isDirectory();
+		assertThat(new ClassPathResource("2").getFile()).isDirectory();
+		assertThat(new ClassPathResource("3").getFile()).isDirectory();
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/classpath/resources/WithResourceTests.java

@@ -0,0 +1,100 @@
+/*
+ * Copyright 2012-2025 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.boot.testsupport.classpath.resources;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link WithResource}.
+ *
+ * @author Andy Wilkinson
+ */
+class WithResourceTests {
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceIsAvailable() throws IOException {
+		assertThat(new ClassPathResource("test").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("content");
+	}
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceIsAvailableFromFileResourcesRoot(@ResourcesRoot File root) {
+		assertThat(new File(root, "test")).hasContent("content");
+	}
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceIsAvailableFromPathResourcesRoot(@ResourcesRoot Path root) {
+		assertThat(root.resolve("test")).hasContent("content");
+	}
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceIsAvailableFromPathResourcePath(
+			@ResourcePath("test") Path resource) {
+		assertThat(resource).hasContent("content");
+	}
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceIsAvailableFromFileResourcePath(
+			@ResourcePath("test") File resource) {
+		assertThat(resource).hasContent("content");
+	}
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceIsAvailableFromStringResourcePath(
+			@ResourcePath("test") String resource) {
+		assertThat(new File(resource)).hasContent("content");
+	}
+
+	@Test
+	@WithResource(name = "test", content = "content")
+	void whenWithResourceIsUsedOnAMethodThenResourceContentIsAvailableAsAString(
+			@ResourceContent("test") String content) {
+		assertThat(content).isEqualTo("content");
+	}
+
+	@Test
+	@WithResource(name = "com/example/test-resource", content = "content")
+	void whenWithResourceNameIncludesADirectoryThenResourceIsAvailable() throws IOException {
+		assertThat(new ClassPathResource("com/example/test-resource").getContentAsString(StandardCharsets.UTF_8))
+			.isEqualTo("content");
+	}
+
+	@Test
+	@WithResource(name = "1", content = "one")
+	@WithResource(name = "2", content = "two")
+	@WithResource(name = "3", content = "three")
+	void whenWithResourceIsRepeatedOnAMethodThenAllResourcesAreAvailable() throws IOException {
+		assertThat(new ClassPathResource("1").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("one");
+		assertThat(new ClassPathResource("2").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("two");
+		assertThat(new ClassPathResource("3").getContentAsString(StandardCharsets.UTF_8)).isEqualTo("three");
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/resources/org/springframework/boot/testsupport/classpath/resources/resource-1.txt

@@ -0,0 +1 @@
+one

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/resources/org/springframework/boot/testsupport/classpath/resources/resource-2.txt

@@ -0,0 +1 @@
+two

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/resources/org/springframework/boot/testsupport/classpath/resources/sub/resource-3.txt

@@ -0,0 +1 @@
+three