Add regression test for linked .classpath and test source folder

When using linked resources for a project's .classpath file defining a
JUnit classpath container or test source folders, they are not detected
by Tycho, such that the JUnit classpath container and the test source
folder are not considered during the build.

This adds a test case demonstrating the integration of the .classpath
file and a test source folder via linked resources.

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/.project

@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>junit5-with-linked-resources</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.m2e.core.maven2Builder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.pde.ManifestBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.pde.SchemaBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.m2e.core.maven2Nature</nature>
+		<nature>org.eclipse.pde.PluginNature</nature>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+	<linkedResources>
+		<!-- A linked file relative to the location of the project -->
+		<link>
+			<name>.classpath</name>
+			<type>1</type>
+			<locationURI>PROJECT_LOC/linkedresources/.classpath</locationURI>
+		</link>
+		<!-- A linked folder relative to the location of the project's parent and defined in a variable -->
+		<link>
+			<name>src_test</name>
+			<type>2</type>
+			<locationURI>VARIABLE_SELFREF_VIA_PARENT/linkedresources/src_test/</locationURI>
+		</link>
+	</linkedResources>
+	<variableList>
+		<variable>
+			<name>VARIABLE_SELFREF_VIA_PARENT</name>
+			<value>$%7BPARENT-1-PROJECT_LOC%7D/junit5-with-linked-files</value>
+		</variable>
+	</variableList>
+</projectDescription>

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/META-INF/MANIFEST.MF

@@ -0,0 +1,7 @@
+Manifest-Version: 1.0
+Bundle-ManifestVersion: 2
+Bundle-Name: junit5-with-linked-resources
+Bundle-SymbolicName: junit5.with.linked.resources
+Bundle-Version: 1.0.0
+Bundle-RequiredExecutionEnvironment: JavaSE-11
+Export-Package: bundle.test

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/build.properties

@@ -0,0 +1,4 @@
+source.. = src/
+output.. = bin/
+bin.includes = META-INF/,\
+               .

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/linkedresources/.classpath

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="src" output="test" path="src_test">
+		<attributes>
+			<attribute name="test" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11">
+		<attributes>
+			<attribute name="module" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/5"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/linkedresources/src_test/bundle/test/AdderTest.java

@@ -0,0 +1,37 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *    Christoph Läubrich. - initial API and implementation
+ *******************************************************************************/
+package bundle.test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+public class AdderTest {
+
+	@Test
+	public void incrementTest() {
+		Counter counter = new Counter();
+		counter.increment(1);
+		counter.increment(3);
+		assertEquals(4, counter.get());
+	}
+
+	@Test
+	public void decrementTest() {
+		assertThrows(IllegalArgumentException.class, () -> {
+			Counter counter = new Counter();
+			counter.increment(-1);
+		});
+	}
+}

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/linkedresources/src_test/bundle/test/SubtractorTest.java

@@ -0,0 +1,45 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *    Christoph Läubrich  - initial API and implementation
+ *******************************************************************************/
+package bundle.test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+public class SubtractorTest {
+
+	@Test
+	public void incrementTest() {
+		CountDown counter = new CountDown(10);
+		counter.decrement(1);
+		counter.decrement(3);
+		assertEquals(6, counter.get());
+	}
+
+	@Test
+	public void decrementTest() {
+		assertThrows(IllegalArgumentException.class, ()->{
+			CountDown counter = new CountDown(10);
+			counter.decrement(-1);
+		});
+	}
+
+	@Test
+	public void decrementTest2() {
+		assertThrows(IllegalStateException.class, ()->{
+			CountDown counter = new CountDown(1);
+			counter.decrement(5);
+		});
+	}
+}

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/pom.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project>
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>org.eclipse.tycho.tycho-its.surefire</groupId>
+	<artifactId>junit5.with.linked.resources</artifactId>
+	<packaging>eclipse-plugin</packaging>
+	<version>1.0.0</version>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.eclipse.tycho</groupId>
+				<artifactId>tycho-maven-plugin</artifactId>
+				<version>${tycho-version}</version>
+				<extensions>true</extensions>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-surefire-plugin</artifactId>
+				<version>3.1.2</version>
+				<dependencies>
+					<dependency>
+						<groupId>org.junit.jupiter</groupId>
+						<artifactId>junit-jupiter-engine</artifactId>
+						<version>5.9.1</version>
+					</dependency>
+				</dependencies>
+				<executions>
+					<execution>
+						<id>surefire-test</id>
+						<phase>test</phase>
+						<goals>
+							<goal>test</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+</project>

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/src/bundle/test/CountDown.java

@@ -0,0 +1,38 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *    Christoph Läubrich. - initial API and implementation
+ *******************************************************************************/
+package bundle.test;
+
+public class CountDown {
+
+	RefMe refFromOtherSourceFolder;
+
+	int count;
+
+	public CountDown(int initalValue) {
+		count = initalValue;
+	}
+
+	public void decrement(int x) {
+		if (x < 0) {
+			throw new IllegalArgumentException();
+		}
+		if (count-x < 0) {
+			throw new IllegalStateException();
+		}
+		count -= x;
+	}
+
+	public int get() {
+		return count;
+	}
+}

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/src/bundle/test/Counter.java

@@ -0,0 +1,29 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *    Christoph Läubrich. - initial API and implementation
+ *******************************************************************************/
+package bundle.test;
+
+public class Counter {
+
+	int count;
+
+	public void increment(int x) {
+		if (x < 0) {
+			throw new IllegalArgumentException();
+		}
+		count += x;
+	}
+
+	public int get() {
+		return count;
+	}
+}

tycho-its/projects/compiler.junitcontainer/junit5-with-linked-resources/src/bundle/test/RefMe.java

@@ -0,0 +1,18 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *    Christoph Läubrich. - initial API and implementation
+ *******************************************************************************/
+
+package bundle.test;
+
+public class RefMe extends Counter{
+
+}

tycho-its/src/test/java/org/eclipse/tycho/test/compiler/CompilerClasspathEntryTest.java

@@ -37,6 +37,16 @@ public void testJUnit5ContainerWithoutTarget() throws Exception {
 		verifier.verifyTextInLog("Tests run: 5, Failures: 0, Errors: 0, Skipped: 0");
 	}
 
+	@Test
+	public void testJUnit5ContainerWithLinkedResources() throws Exception {
+		Verifier verifier = getVerifier("compiler.junitcontainer/junit5-with-linked-resources", false, true);
+		verifier.executeGoal("test");
+		verifier.verifyErrorFreeLog();
+		verifier.verifyTextInLog("-- in bundle.test.AdderTest");
+		verifier.verifyTextInLog("-- in bundle.test.SubtractorTest");
+		verifier.verifyTextInLog("Tests run: 5, Failures: 0, Errors: 0, Skipped: 0");
+	}
+
 	@Test
 	public void testJUnit4Container() throws Exception {
 		Verifier verifier = getVerifier("compiler.junitcontainer/junit4-in-bundle", true);