Introduce CLI for triggering AOT test context processing

This commit introduces TestAotProcessor which replaces
ProcessTestsAheadOfTimeCommand, removes the dependency on picocli, and
aligns with the implementation of the AotProcessor in Spring Boot.

TestAotProcessor is a command-line application (CLI) that scans the
provided classpath roots for Spring integration test classes and then
generates AOT artifacts for those test classes in the provided output
directories.

This CLI is only intended to be used by build tools.

Closes gh-28825

spring-test/src/main/java/org/springframework/test/context/aot/ProcessTestsAheadOfTimeCommand.java

@@ -1,91 +0,0 @@
-/*
- * Copyright 2002-2022 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.aot;
-
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.Set;
-import java.util.concurrent.Callable;
-import java.util.stream.Stream;
-
-import picocli.CommandLine;
-import picocli.CommandLine.Command;
-import picocli.CommandLine.Option;
-import picocli.CommandLine.Parameters;
-
-import org.springframework.aot.generate.FileSystemGeneratedFiles;
-import org.springframework.aot.generate.GeneratedFiles;
-import org.springframework.aot.nativex.FileNativeConfigurationWriter;
-import org.springframework.aot.nativex.NativeConfigurationWriter;
-
-/**
- * Command-line application that scans the provided classpath roots for Spring
- * integration test classes and then generates AOT artifacts for those test
- * classes in the provided output directories.
- *
- * @author Sam Brannen
- * @since 6.0
- * @see TestClassScanner
- * @see TestContextAotGenerator
- * @see FileNativeConfigurationWriter
- */
-@Command(mixinStandardHelpOptions = true, description = "Process test classes ahead of time")
-public class ProcessTestsAheadOfTimeCommand implements Callable<Integer> {
-
-	@Parameters(index = "0", arity = "1..*", description = "Classpath roots for compiled test classes.")
-	private Path[] testClasspathRoots;
-
-	@Option(names = {"--packages"}, required = false, description = "Test packages to scan. This is optional any only intended for testing purposes.")
-	private String[] packagesToScan = new String[0];
-
-	@Option(names = {"--sources-out"}, required = true, description = "Output path for the generated sources.")
-	private Path sourcesOutputPath;
-
-	@Option(names = {"--resources-out"}, required = true, description = "Output path for the generated resources.")
-	private Path resourcesOutputPath;
-
-
-	@Override
-	public Integer call() throws Exception {
-		TestClassScanner testClassScanner = new TestClassScanner(Set.of(this.testClasspathRoots));
-		Stream<Class<?>> testClasses = testClassScanner.scan(this.packagesToScan);
-
-		// TODO Determine if we need to support CLASS output path.
-		Path tempDir = Files.createTempDirectory("classes");
-		GeneratedFiles generatedFiles = new FileSystemGeneratedFiles(kind -> switch(kind) {
-				case SOURCE -> this.sourcesOutputPath;
-				case RESOURCE -> this.resourcesOutputPath;
-				case CLASS -> tempDir;
-		});
-		TestContextAotGenerator generator = new TestContextAotGenerator(generatedFiles);
-		generator.processAheadOfTime(testClasses);
-
-		NativeConfigurationWriter writer = new FileNativeConfigurationWriter(this.resourcesOutputPath);
-		writer.write(generator.getRuntimeHints());
-
-		return 0;
-	}
-
-	static int execute(String[] args) throws Exception {
-		return new CommandLine(new ProcessTestsAheadOfTimeCommand()).execute(args);
-	}
-
-	public static void main(String[] args) throws Exception {
-		System.exit(execute(args));
-	}
-
-}

spring-test/src/main/java/org/springframework/test/context/aot/TestAotProcessor.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2002-2022 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.aot;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Arrays;
+import java.util.Set;
+import java.util.stream.Stream;
+
+import org.springframework.aot.generate.FileSystemGeneratedFiles;
+import org.springframework.aot.generate.GeneratedFiles;
+import org.springframework.aot.generate.GeneratedFiles.Kind;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.nativex.FileNativeConfigurationWriter;
+import org.springframework.util.Assert;
+import org.springframework.util.FileSystemUtils;
+
+/**
+ * Command-line application that scans the provided classpath roots for Spring
+ * integration test classes and then generates AOT artifacts for those test
+ * classes in the provided output directories.
+ *
+ * <p><strong>For internal use only.</strong>
+ *
+ * @author Sam Brannen
+ * @author Stephane Nicoll
+ * @author Andy Wilkinson
+ * @author Phillip Webb
+ * @since 6.0
+ * @see TestClassScanner
+ * @see TestContextAotGenerator
+ * @see FileNativeConfigurationWriter
+ * @see org.springframework.boot.AotProcessor
+ */
+public class TestAotProcessor {
+
+	private final Path[] classpathRoots;
+
+	private final Path sourceOutput;
+
+	private final Path resourceOutput;
+
+	private final Path classOutput;
+
+	private final String groupId;
+
+	private final String artifactId;
+
+
+	/**
+	 * Create a new processor for the specified test classpath roots and
+	 * general settings.
+	 *
+	 * @param classpathRoots the classpath roots to scan for test classes
+	 * @param sourceOutput the location of generated sources
+	 * @param resourceOutput the location of generated resources
+	 * @param classOutput the location of generated classes
+	 * @param groupId the group ID of the application, used to locate
+	 * {@code native-image.properties}
+	 * @param artifactId the artifact ID of the application, used to locate
+	 * {@code native-image.properties}
+	 */
+	public TestAotProcessor(Path[] classpathRoots, Path sourceOutput, Path resourceOutput, Path classOutput,
+			String groupId, String artifactId) {
+
+		this.classpathRoots = classpathRoots;
+		this.sourceOutput = sourceOutput;
+		this.resourceOutput = resourceOutput;
+		this.classOutput = classOutput;
+		this.groupId = groupId;
+		this.artifactId = artifactId;
+	}
+
+
+	/**
+	 * Trigger processing of the test classes in the configured classpath roots.
+	 */
+	public void process() {
+		deleteExistingOutput();
+		performAotProcessing();
+	}
+
+	private void deleteExistingOutput() {
+		deleteExistingOutput(this.sourceOutput, this.resourceOutput, this.classOutput);
+	}
+
+	private void deleteExistingOutput(Path... paths) {
+		for (Path path : paths) {
+			try {
+				FileSystemUtils.deleteRecursively(path);
+			}
+			catch (IOException ex) {
+				throw new UncheckedIOException("Failed to delete existing output in '%s'".formatted(path), ex);
+			}
+		}
+	}
+
+	private void performAotProcessing() {
+		TestClassScanner scanner = new TestClassScanner(Set.of(this.classpathRoots));
+		Stream<Class<?>> testClasses = scanner.scan();
+
+		GeneratedFiles generatedFiles = new FileSystemGeneratedFiles(this::getRoot);
+		TestContextAotGenerator generator = new TestContextAotGenerator(generatedFiles);
+		generator.processAheadOfTime(testClasses);
+
+		writeHints(generator.getRuntimeHints());
+	}
+
+	private Path getRoot(Kind kind) {
+		return switch (kind) {
+			case SOURCE -> this.sourceOutput;
+			case RESOURCE -> this.resourceOutput;
+			case CLASS -> this.classOutput;
+		};
+	}
+
+	private void writeHints(RuntimeHints hints) {
+		FileNativeConfigurationWriter writer =
+				new FileNativeConfigurationWriter(this.resourceOutput, this.groupId, this.artifactId);
+		writer.write(hints);
+	}
+
+
+	public static void main(String[] args) {
+		int requiredArgs = 6;
+		Assert.isTrue(args.length >= requiredArgs, () ->
+				"Usage: %s <classpathRoots> <sourceOutput> <resourceOutput> <classOutput> <groupId> <artifactId>"
+					.formatted(TestAotProcessor.class.getName()));
+		Path[] classpathRoots = Arrays.stream(args[0].split(File.pathSeparator)).map(Paths::get).toArray(Path[]::new);
+		Path sourceOutput = Paths.get(args[1]);
+		Path resourceOutput = Paths.get(args[2]);
+		Path classOutput = Paths.get(args[3]);
+		String groupId = args[4];
+		String artifactId = args[5];
+		new TestAotProcessor(classpathRoots, sourceOutput, resourceOutput, classOutput, groupId, artifactId).process();
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/aot/AbstractAotTests.java

@@ -88,4 +88,13 @@ abstract class AbstractAotTests {
 		}
 	}
 
+	Path classpathRoot(Class<?> clazz) {
+		try {
+			return Paths.get(clazz.getProtectionDomain().getCodeSource().getLocation().toURI());
+		}
+		catch (Exception ex) {
+			throw new RuntimeException(ex);
+		}
+	}
+
 }

spring-test/src/test/java/org/springframework/test/context/aot/ProcessTestsAheadOfTimeCommandTests.java

@@ -1,71 +0,0 @@
-/*
- * Copyright 2002-2022 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.aot;
-
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.List;
-
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.io.CleanupMode;
-import org.junit.jupiter.api.io.TempDir;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-/**
- * Tests for {@link ProcessTestsAheadOfTimeCommand}.
- *
- * @author Sam Brannen
- * @since 6.0
- */
-class ProcessTestsAheadOfTimeCommandTests extends AbstractAotTests {
-
-	@Test
-	void execute(@TempDir(cleanup = CleanupMode.ON_SUCCESS) Path tempDir) throws Exception {
-		Path sourcesOutputPath = tempDir.resolve("src/test/java").toAbsolutePath();
-		Path resourcesOutputPath = tempDir.resolve("src/test/resources").toAbsolutePath();
-		String testPackage = "org.springframework.test.context.aot.samples.basic";
-		String[] args = {
-				"--sources-out=" + sourcesOutputPath,
-				"--resources-out=" + resourcesOutputPath,
-				"--packages=" + testPackage,
-				classpathRoot().toString()
-			};
-		int exitCode = ProcessTestsAheadOfTimeCommand.execute(args);
-		assertThat(exitCode).as("exit code").isZero();
-
-		assertThat(findFiles(sourcesOutputPath)).containsExactlyInAnyOrder(
-				expectedSourceFilesForBasicSpringTests);
-
-		assertThat(findFiles(resourcesOutputPath)).contains(
-				"META-INF/native-image/reflect-config.json",
-				"META-INF/native-image/resource-config.json",
-				"META-INF/native-image/proxy-config.json");
-	}
-
-	private static List<String> findFiles(Path outputPath) throws IOException {
-		int lengthOfOutputPath = outputPath.toFile().getAbsolutePath().length() + 1;
-		return Files.find(outputPath, Integer.MAX_VALUE,
-					(path, attributes) -> attributes.isRegularFile())
-				.map(Path::toAbsolutePath)
-				.map(Path::toString)
-				.map(path -> path.substring(lengthOfOutputPath))
-				.toList();
-	}
-
-}

spring-test/src/test/java/org/springframework/test/context/aot/TestAotProcessorTests.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright 2002-2022 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.aot;
+
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.CleanupMode;
+import org.junit.jupiter.api.io.TempDir;
+
+import org.springframework.test.context.aot.samples.basic.BasicSpringJupiterSharedConfigTests;
+import org.springframework.test.context.aot.samples.basic.BasicSpringJupiterTests;
+import org.springframework.test.context.aot.samples.basic.BasicSpringTestNGTests;
+import org.springframework.test.context.aot.samples.basic.BasicSpringVintageTests;
+import org.springframework.util.ClassUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link TestAotProcessor}.
+ *
+ * @author Sam Brannen
+ * @since 6.0
+ */
+class TestAotProcessorTests extends AbstractAotTests {
+
+	@Test
+	void process(@TempDir(cleanup = CleanupMode.ON_SUCCESS) Path tempDir) throws Exception {
+		// Limit the scope of this test by creating a new classpath root on the fly.
+		Path classpathRoot = Files.createDirectories(tempDir.resolve("build/classes"));
+		Stream.of(
+				BasicSpringJupiterSharedConfigTests.class,
+				BasicSpringJupiterTests.class,
+				BasicSpringJupiterTests.NestedTests.class,
+				BasicSpringTestNGTests.class,
+				BasicSpringVintageTests.class
+			).forEach(testClass -> copy(testClass, classpathRoot));
+
+		Path[] classpathRoots = { classpathRoot };
+		Path sourceOutput = tempDir.resolve("generated/sources");
+		Path resourceOutput = tempDir.resolve("generated/resources");
+		Path classOutput = tempDir.resolve("generated/classes");
+		String groupId = "org.example";
+		String artifactId = "app-tests";
+
+		TestAotProcessor processor = new TestAotProcessor(classpathRoots, sourceOutput, resourceOutput, classOutput, groupId, artifactId);
+		processor.process();
+
+		assertThat(findFiles(sourceOutput)).containsExactlyInAnyOrder(
+				expectedSourceFilesForBasicSpringTests);
+
+		assertThat(findFiles(resourceOutput)).contains(
+				"META-INF/native-image/org.example/app-tests/reflect-config.json",
+				"META-INF/native-image/org.example/app-tests/resource-config.json",
+				"META-INF/native-image/org.example/app-tests/proxy-config.json");
+	}
+
+	private void copy(Class<?> testClass, Path destination) {
+		String classFilename = ClassUtils.convertClassNameToResourcePath(testClass.getName()) + ".class";
+		Path source = classpathRoot(testClass).resolve(classFilename);
+		Path target = destination.resolve(classFilename);
+		try {
+			Files.createDirectories(target.getParent());
+			Files.copy(source, target);
+		}
+		catch (IOException ex) {
+			throw new UncheckedIOException(ex);
+		}
+	}
+
+	private static List<String> findFiles(Path outputPath) throws IOException {
+		int prefixLength = outputPath.toFile().getAbsolutePath().length() + 1;
+		return Files.find(outputPath, Integer.MAX_VALUE, (path, attributes) -> attributes.isRegularFile())
+				.map(Path::toAbsolutePath)
+				.map(Path::toString)
+				.map(path -> path.substring(prefixLength))
+				.toList();
+	}
+
+}