Add @JimfsTempDir and JimfsTempDirFactory

pom.xml

@@ -7,7 +7,7 @@
   <version>0.1.0-SNAPSHOT</version>
 
   <name>Jimfs JUnit Jupiter</name>
-  <description>A JUnit Jupiter `@TempDir` extension based on Jimfs</description>
+  <description>A JUnit Jupiter `@TempDir` extension based on the in-memory file system Jimfs</description>
   <url>https://github.com/scordio/jimfs-junit-jupiter</url>
   <inceptionYear>2024</inceptionYear>
   <licenses>
@@ -64,6 +64,12 @@
       <scope>provided</scope>
     </dependency>
     <!-- Test -->
+    <dependency>
+      <groupId>org.assertj</groupId>
+      <artifactId>assertj-core</artifactId>
+      <version>3.26.3</version>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>org.junit.jupiter</groupId>
       <artifactId>junit-jupiter</artifactId>

src/main/java/io/github/scordio/jimfs/junit/jupiter/JimfsTempDir.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright © 2024 Stefano Cordio ([email protected])
+ *
+ * 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
+ *
+ *     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 io.github.scordio.jimfs.junit.jupiter;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import java.util.function.Supplier;
+import org.junit.jupiter.api.io.TempDir;
+
+@Target({ElementType.ANNOTATION_TYPE, ElementType.FIELD, ElementType.PARAMETER})
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+@TempDir(factory = JimfsTempDirFactory.class)
+public @interface JimfsTempDir {
+
+  Configuration value() default Configuration.FOR_CURRENT_PLATFORM;
+
+  enum Configuration {
+    FOR_CURRENT_PLATFORM(com.google.common.jimfs.Configuration::forCurrentPlatform),
+    OS_X(com.google.common.jimfs.Configuration::osX),
+    UNIX(com.google.common.jimfs.Configuration::unix),
+    WINDOWS(com.google.common.jimfs.Configuration::windows);
+
+    private final Supplier<com.google.common.jimfs.Configuration> configuration;
+
+    Configuration(Supplier<com.google.common.jimfs.Configuration> configuration) {
+      this.configuration = configuration;
+    }
+
+    Supplier<com.google.common.jimfs.Configuration> getConfiguration() {
+      return configuration;
+    }
+  }
+}

src/main/java/io/github/scordio/jimfs/junit/jupiter/JimfsTempDirFactory.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright © 2024 Stefano Cordio ([email protected])
+ *
+ * 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
+ *
+ *     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 io.github.scordio.jimfs.junit.jupiter;
+
+import com.google.common.jimfs.Configuration;
+import com.google.common.jimfs.Jimfs;
+import java.io.IOException;
+import java.nio.file.FileSystem;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.function.Supplier;
+import org.junit.jupiter.api.extension.AnnotatedElementContext;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.api.io.TempDirFactory;
+
+public final class JimfsTempDirFactory implements TempDirFactory {
+
+  private static final String DEFAULT_PREFIX = "junit-";
+
+  private FileSystem fileSystem;
+
+  /** {@inheritDoc} */
+  @Override
+  public Path createTempDirectory(
+      AnnotatedElementContext elementContext, ExtensionContext extensionContext)
+      throws IOException {
+    Supplier<Configuration> configuration =
+        elementContext
+            .findAnnotation(JimfsTempDir.class)
+            .map(JimfsTempDir::value)
+            .map(JimfsTempDir.Configuration::getConfiguration)
+            .orElse(Configuration::forCurrentPlatform);
+
+    fileSystem = Jimfs.newFileSystem(configuration.get());
+    Path root = fileSystem.getRootDirectories().iterator().next();
+    return Files.createTempDirectory(root, DEFAULT_PREFIX);
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void close() throws IOException {
+    fileSystem.close();
+  }
+}

src/test/java/io/github/scordio/jimfs/junit/jupiter/JimfsTempDirFactoryTests.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright © 2024 Stefano Cordio ([email protected])
+ *
+ * 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
+ *
+ *     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 io.github.scordio.jimfs.junit.jupiter;
+
+import static io.github.scordio.jimfs.junit.jupiter.Requirements.osXFileSystem;
+import static io.github.scordio.jimfs.junit.jupiter.Requirements.unixFileSystem;
+import static io.github.scordio.jimfs.junit.jupiter.Requirements.windowsFileSystem;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.condition.OS.MAC;
+import static org.junit.jupiter.api.condition.OS.WINDOWS;
+
+import java.nio.file.Path;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.DisabledOnOs;
+import org.junit.jupiter.api.condition.EnabledOnOs;
+import org.junit.jupiter.api.io.TempDir;
+
+class JimfsTempDirFactoryTests {
+
+  @TempDir(factory = JimfsTempDirFactory.class)
+  Path tempDir;
+
+  @EnabledOnOs(MAC)
+  @Test
+  void should_use_os_x_configuration() {
+    assertThat(tempDir).satisfies(osXFileSystem());
+  }
+
+  @DisabledOnOs({MAC, WINDOWS})
+  @Test
+  void should_use_unix_configuration() {
+    assertThat(tempDir).satisfies(unixFileSystem());
+  }
+
+  @EnabledOnOs(WINDOWS)
+  @Test
+  void should_use_windows_configuration() {
+    assertThat(tempDir).satisfies(windowsFileSystem());
+  }
+}

src/test/java/io/github/scordio/jimfs/junit/jupiter/JimfsTempDirTests.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright © 2024 Stefano Cordio ([email protected])
+ *
+ * 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
+ *
+ *     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 io.github.scordio.jimfs.junit.jupiter;
+
+import static io.github.scordio.jimfs.junit.jupiter.JimfsTempDir.Configuration.FOR_CURRENT_PLATFORM;
+import static io.github.scordio.jimfs.junit.jupiter.JimfsTempDir.Configuration.OS_X;
+import static io.github.scordio.jimfs.junit.jupiter.JimfsTempDir.Configuration.UNIX;
+import static io.github.scordio.jimfs.junit.jupiter.JimfsTempDir.Configuration.WINDOWS;
+import static io.github.scordio.jimfs.junit.jupiter.Requirements.osXFileSystem;
+import static io.github.scordio.jimfs.junit.jupiter.Requirements.unixFileSystem;
+import static io.github.scordio.jimfs.junit.jupiter.Requirements.windowsFileSystem;
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.nio.file.Path;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.DisabledOnOs;
+import org.junit.jupiter.api.condition.EnabledOnOs;
+import org.junit.jupiter.api.condition.OS;
+
+class JimfsTempDirTests {
+
+  @Nested
+  class With_Default_Configuration {
+
+    @JimfsTempDir Path tempDir;
+
+    @EnabledOnOs(OS.MAC)
+    @Test
+    void should_use_os_x_configuration() {
+      assertThat(tempDir).satisfies(osXFileSystem());
+    }
+
+    @DisabledOnOs({OS.MAC, OS.WINDOWS})
+    @Test
+    void should_use_unix_configuration() {
+      assertThat(tempDir).satisfies(unixFileSystem());
+    }
+
+    @EnabledOnOs(OS.WINDOWS)
+    @Test
+    void should_use_windows_configuration() {
+      assertThat(tempDir).satisfies(windowsFileSystem());
+    }
+  }
+
+  @Nested
+  class With_FOR_CURRENT_PLATFORM_Configuration {
+
+    @JimfsTempDir(FOR_CURRENT_PLATFORM)
+    Path tempDir;
+
+    @EnabledOnOs(OS.MAC)
+    @Test
+    void should_use_os_x_configuration() {
+      assertThat(tempDir).satisfies(osXFileSystem());
+    }
+
+    @DisabledOnOs({OS.MAC, OS.WINDOWS})
+    @Test
+    void should_use_unix_configuration() {
+      assertThat(tempDir).satisfies(unixFileSystem());
+    }
+
+    @EnabledOnOs(OS.WINDOWS)
+    @Test
+    void should_use_windows_configuration() {
+      assertThat(tempDir).satisfies(windowsFileSystem());
+    }
+  }
+
+  @Nested
+  class With_OS_X_Configuration {
+
+    @JimfsTempDir(OS_X)
+    Path tempDir;
+
+    @Test
+    void should_use_os_x_configuration() {
+      assertThat(tempDir).satisfies(osXFileSystem());
+    }
+  }
+
+  @Nested
+  class With_UNIX_Configuration {
+
+    @JimfsTempDir(UNIX)
+    Path tempDir;
+
+    @Test
+    void should_use_unix_configuration() {
+      assertThat(tempDir).satisfies(unixFileSystem());
+    }
+  }
+
+  @Nested
+  class With_WINDOWS_Configuration {
+
+    @JimfsTempDir(WINDOWS)
+    Path tempDir;
+
+    @Test
+    void should_use_windows_configuration() {
+      assertThat(tempDir).satisfies(windowsFileSystem());
+    }
+  }
+}

src/test/java/io/github/scordio/jimfs/junit/jupiter/Requirements.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright © 2024 Stefano Cordio ([email protected])
+ *
+ * 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
+ *
+ *     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 io.github.scordio.jimfs.junit.jupiter;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.nio.file.Path;
+import java.util.function.Consumer;
+
+class Requirements {
+
+  static Consumer<Path> osXFileSystem() {
+    return tempDir -> {
+      assertThat(tempDir.getFileSystem().provider().getScheme()).isEqualTo("jimfs");
+      assertThat(tempDir.getFileSystem().getSeparator()).isEqualTo("/");
+      assertThat(tempDir.getFileSystem().getRootDirectories())
+          .map(Path::toString)
+          .containsExactly("/");
+    };
+  }
+
+  static Consumer<Path> unixFileSystem() {
+    return tempDir -> {
+      assertThat(tempDir.getFileSystem().provider().getScheme()).isEqualTo("jimfs");
+      assertThat(tempDir.getFileSystem().getSeparator()).isEqualTo("/");
+      assertThat(tempDir.getFileSystem().getRootDirectories())
+          .map(Path::toString)
+          .containsExactly("/");
+    };
+  }
+
+  static Consumer<Path> windowsFileSystem() {
+    return tempDir -> {
+      assertThat(tempDir.getFileSystem().provider().getScheme()).isEqualTo("jimfs");
+      assertThat(tempDir.getFileSystem().getSeparator()).isEqualTo("\\");
+      assertThat(tempDir.getFileSystem().getRootDirectories())
+          .map(Path::toString)
+          .containsExactly("C:\\");
+    };
+  }
+}

src/test/resources/junit-platform.properties

@@ -0,0 +1 @@
+junit.jupiter.displayname.generator.default=org.junit.jupiter.api.DisplayNameGenerator$ReplaceUnderscores