Fix resource targetPath resolution to be relative to output directory (fixes #11381)

impl/maven-core/src/main/java/org/apache/maven/project/ConnectedResource.java

@@ -42,13 +42,53 @@ class ConnectedResource extends Resource {
                 .includes(sourceRoot.includes())
                 .excludes(sourceRoot.excludes())
                 .filtering(Boolean.toString(sourceRoot.stringFiltering()))
-                .targetPath(sourceRoot.targetPath().map(Path::toString).orElse(null))
+                .targetPath(computeRelativeTargetPath(sourceRoot, scope, project))
                 .build());
         this.originalSourceRoot = sourceRoot;
         this.scope = scope;
         this.project = project;
     }
 
+    /**
+     * Computes the targetPath relative to the output directory.
+     * In Maven 3 API, Resource.getTargetPath() is expected to be relative to the output directory
+     * (e.g., "custom-output"), while SourceRoot.targetPath() is relative to the project basedir
+     * (e.g., "target/classes/custom-output").
+     */
+    private static String computeRelativeTargetPath(SourceRoot sourceRoot, ProjectScope scope, MavenProject project) {
+        return sourceRoot
+                .targetPath()
+                .map(targetPath -> {
+                    // Get the output directory for this scope
+                    String outputDir = scope == ProjectScope.MAIN
+                            ? project.getBuild().getOutputDirectory()
+                            : project.getBuild().getTestOutputDirectory();
+                    Path outputDirPath = Path.of(outputDir);
+
+                    // If targetPath is absolute, try to make it relative to the output directory
+                    if (targetPath.isAbsolute()) {
+                        if (targetPath.startsWith(outputDirPath)) {
+                            return outputDirPath.relativize(targetPath).toString();
+                        }
+                        return targetPath.toString();
+                    }
+
+                    // If targetPath is relative, check if it starts with the output directory
+                    // (e.g., "target/classes/custom-output" should become "custom-output")
+                    Path baseDir = project.getBaseDirectory();
+                    Path resolvedTargetPath = baseDir.resolve(targetPath);
+                    Path resolvedOutputDir = baseDir.resolve(outputDirPath);
+
+                    if (resolvedTargetPath.startsWith(resolvedOutputDir)) {
+                        return resolvedOutputDir.relativize(resolvedTargetPath).toString();
+                    }
+
+                    // Otherwise, return as-is
+                    return targetPath.toString();
+                })
+                .orElse(null);
+    }
+
     @Override
     public void addInclude(String include) {
         // Update the underlying Resource model

impl/maven-core/src/test/java/org/apache/maven/project/ResourceIncludeTest.java

@@ -46,6 +46,10 @@ void setUp() {
         // Set a dummy pom file to establish the base directory
         project.setFile(new java.io.File("./pom.xml"));
 
+        // Set build output directories
+        project.getBuild().setOutputDirectory("target/classes");
+        project.getBuild().setTestOutputDirectory("target/test-classes");
+
         // Add a resource source root to the project
         project.addSourceRoot(
                 new DefaultSourceRoot(ProjectScope.MAIN, Language.RESOURCES, Path.of("src/main/resources")));
@@ -199,7 +203,7 @@ void testTargetPathPreservedWithConnectedResource() {
         resourceWithTarget.setDirectory("src/main/custom");
         resourceWithTarget.setTargetPath("custom-output");
 
-        // Convert through DefaultSourceRoot to ensure targetPath extraction works
+        // Convert through DefaultSourceRoot to ensure targetPath is preserved
         DefaultSourceRoot sourceRootFromResource =
                 new DefaultSourceRoot(project.getBaseDirectory(), ProjectScope.MAIN, resourceWithTarget.getDelegate());
 

impl/maven-impl/src/test/java/org/apache/maven/impl/DefaultSourceRootTest.java

@@ -183,10 +183,11 @@ void testRelativeTestTargetPath() {
                 source.targetPath().orElseThrow());
     }
 
-    /*MNG-11062*/
+    /*GH-11381*/
     @Test
     void testExtractsTargetPathFromResource() {
-        // Test the Resource constructor that was broken in the regression
+        // Test the Resource constructor with relative targetPath
+        // targetPath should be kept as relative path
         Resource resource = Resource.newBuilder()
                 .directory("src/test/resources")
                 .targetPath("test-output")
@@ -196,13 +197,14 @@ void testExtractsTargetPathFromResource() {
 
         Optional<Path> targetPath = sourceRoot.targetPath();
         assertTrue(targetPath.isPresent(), "targetPath should be present");
-        assertEquals(Path.of("myproject", "test-output"), targetPath.get());
+        assertEquals(
+                Path.of("myproject/test-output"), targetPath.get(), "targetPath should be resolved against baseDir");
         assertEquals(Path.of("myproject", "src", "test", "resources"), sourceRoot.directory());
         assertEquals(ProjectScope.TEST, sourceRoot.scope());
         assertEquals(Language.RESOURCES, sourceRoot.language());
     }
 
-    /*MNG-11062*/
+    /*GH-11381*/
     @Test
     void testHandlesNullTargetPathFromResource() {
         // Test null targetPath handling
@@ -216,7 +218,7 @@ void testHandlesNullTargetPathFromResource() {
         assertFalse(targetPath.isPresent(), "targetPath should be empty when null");
     }
 
-    /*MNG-11062*/
+    /*GH-11381*/
     @Test
     void testHandlesEmptyTargetPathFromResource() {
         // Test empty string targetPath
@@ -231,7 +233,7 @@ void testHandlesEmptyTargetPathFromResource() {
         assertFalse(targetPath.isPresent(), "targetPath should be empty for empty string");
     }
 
-    /*MNG-11062*/
+    /*GH-11381*/
     @Test
     void testHandlesPropertyPlaceholderInTargetPath() {
         // Test property placeholder preservation
@@ -244,10 +246,13 @@ void testHandlesPropertyPlaceholderInTargetPath() {
 
         Optional<Path> targetPath = sourceRoot.targetPath();
         assertTrue(targetPath.isPresent(), "Property placeholder targetPath should be present");
-        assertEquals(Path.of("myproject", "${project.build.directory}/custom"), targetPath.get());
+        assertEquals(
+                Path.of("myproject/${project.build.directory}/custom"),
+                targetPath.get(),
+                "Property placeholder should be resolved against baseDir");
     }
 
-    /*MNG-11062*/
+    /*GH-11381*/
     @Test
     void testResourceConstructorRequiresNonNullDirectory() {
         // Test that null directory throws exception
@@ -260,7 +265,7 @@ void testResourceConstructorRequiresNonNullDirectory() {
                 "Should throw exception for null directory");
     }
 
-    /*MNG-11062*/
+    /*GH-11381*/
     @Test
     void testResourceConstructorPreservesOtherProperties() {
         // Test that other Resource properties are correctly preserved
@@ -276,7 +281,9 @@ void testResourceConstructorPreservesOtherProperties() {
 
         // Verify all properties are preserved
         assertEquals(
-                Path.of("myproject", "test-classes"), sourceRoot.targetPath().orElseThrow());
+                Path.of("myproject/test-classes"),
+                sourceRoot.targetPath().orElseThrow(),
+                "targetPath should be resolved against baseDir");
         assertTrue(sourceRoot.stringFiltering(), "Filtering should be true");
         assertEquals(1, sourceRoot.includes().size());
         assertTrue(sourceRoot.includes().contains("*.properties"));

its/core-it-suite/src/test/java/org/apache/maven/it/MavenITgh11381ResourceTargetPathTest.java

@@ -0,0 +1,61 @@
+/*
+ * 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.maven.it;
+
+import java.io.File;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * This is a test set for <a href="https://github.com/apache/maven/issues/11381">GH-11381</a>.
+ *
+ * Verifies that relative targetPath in resources is resolved relative to the output directory
+ * (target/classes) and not relative to the project base directory, maintaining Maven 3.x behavior.
+ *
+ * @since 4.0.0-rc-4
+ */
+class MavenITgh11381ResourceTargetPathTest extends AbstractMavenIntegrationTestCase {
+
+    /**
+     * Verify that resources with relative targetPath are copied to target/classes/targetPath
+     * and not to the project root directory.
+     *
+     * @throws Exception in case of failure
+     */
+    @Test
+    void testRelativeTargetPathInResources() throws Exception {
+        File testDir = extractResources("/gh-11381");
+
+        Verifier verifier = newVerifier(testDir.getAbsolutePath());
+        verifier.setAutoclean(false);
+        verifier.deleteDirectory("target");
+        verifier.addCliArgument("process-resources");
+        verifier.execute();
+        verifier.verifyErrorFreeLog();
+
+        // Verify that resources were copied to target/classes/target-dir (Maven 3.x behavior)
+        verifier.verifyFilePresent("target/classes/target-dir/test.yml");
+        verifier.verifyFilePresent("target/classes/target-dir/subdir/another.yml");
+
+        // Verify that resources were NOT copied to the project root target-dir directory
+        verifier.verifyFileNotPresent("target-dir/test.yml");
+        verifier.verifyFileNotPresent("target-dir/subdir/another.yml");
+    }
+}
+

its/core-it-suite/src/test/resources/gh-11381/pom.xml

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+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
+
+  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.
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>org.apache.maven.its.gh11381</groupId>
+  <artifactId>test</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <name>Maven Integration Test :: GH-11381</name>
+  <description>Test for relative targetPath in resources - should be relative to output directory</description>
+
+  <build>
+    <resources>
+      <resource>
+        <directory>${project.basedir}/rest</directory>
+        <targetPath>target-dir</targetPath>
+        <includes>
+          <include>**/*.yml</include>
+        </includes>
+      </resource>
+    </resources>
+  </build>
+</project>
+

its/core-it-suite/src/test/resources/gh-11381/rest/subdir/another.yml

@@ -0,0 +1,4 @@
+# Another test YAML file for GH-11381
+another:
+  test: data
+

its/core-it-suite/src/test/resources/gh-11381/rest/test.yml

@@ -0,0 +1,4 @@
+# Test YAML file for GH-11381
+test:
+  key: value
+