[FIXED JENKINS-18918] From plugins we must use target/ not target/cla…

…sses/ to unpack Maven.

Also cleaning up variable names to be less misleading.

Note that new File("target") is really a bad idea since we cannot predict the CWD in effect when Maven is run.
(From the standard bin/mvn launcher, it seems that it will always be *some* Maven project at least.
This may not be true for Maven run embedded from various tools.)
But leaving that as is for now, since it is not clear how else we would find the project location.
(new File(env.description().getTestClass().getProtectionDomain().getCodeSource().getLocation().toURI()).getParentFile() might work but it is pretty hacky.)
(cherry picked from commit 2152cf4)

changelog.html

@@ -92,6 +92,9 @@ <h3><a name=v1.524>What's new in 1.524</a> <!--=DATE=--></h3>
   <li class='major bug'>
     Since 1.517, Maven projects using Maven 2 could not build projects using extensions depending on Apache Commons Codec.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-18178">issue 18178</a>)
+  <li class=bug>
+    Test harness was packing copies of Maven into plugin archives under some conditions.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-18918">issue 18918</a>)
   <li class=bug>
     Provided maven settings.xml in maven builder is lost.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-15976">issue 15976</a>)

test/src/main/java/org/jvnet/hudson/test/HudsonTestCase.java

@@ -585,11 +585,11 @@ protected MavenInstallation configureMaven3() throws Exception {
      */
     protected MavenInstallation configureDefaultMaven(String mavenVersion, int mavenReqVersion) throws Exception {
         // Does it exists in the buildDirectory - i.e. already extracted from previous test?
-        // see maven-junit-plugin systemProperties: buildDirectory -> ${project.build.directory} (so no reason to be null ;-) )
-        String buildDirectory = System.getProperty( "buildDirectory", "./target/classes/" );
-        File mavenAlreadyInstalled = new File(buildDirectory, mavenVersion);
-        if (mavenAlreadyInstalled.exists()) {
-            MavenInstallation mavenInstallation = new MavenInstallation("default",mavenAlreadyInstalled.getAbsolutePath(), NO_PROPERTIES);
+        // defined in jenkins-test-harness POM, but not plugins; TODO should not use relative paths as we do not know what CWD is
+        File buildDirectory = new File(System.getProperty("buildDirectory", "target"));
+        File mvnHome = new File(buildDirectory, mavenVersion);
+        if (mvnHome.exists()) {
+            MavenInstallation mavenInstallation = new MavenInstallation("default", mvnHome.getAbsolutePath(), NO_PROPERTIES);
             jenkins.getDescriptorByType(Maven.DescriptorImpl.class).setInstallations(mavenInstallation);
             return mavenInstallation;
         }
@@ -606,18 +606,17 @@ protected MavenInstallation configureDefaultMaven(String mavenVersion, int maven
 
         // otherwise extract the copy we have.
         // this happens when a test is invoked from an IDE, for example.
-        LOGGER.warning("Extracting a copy of Maven bundled in the test harness. " +
+        LOGGER.warning("Extracting a copy of Maven bundled in the test harness into " + mvnHome + ". " +
                 "To avoid a performance hit, set the system property 'maven.home' to point to a Maven2 installation.");
         FilePath mvn = jenkins.getRootPath().createTempFile("maven", "zip");
         mvn.copyFrom(HudsonTestCase.class.getClassLoader().getResource(mavenVersion + "-bin.zip"));
-        File mvnHome =  new File(buildDirectory);
-        mvn.unzip(new FilePath(mvnHome));
+        mvn.unzip(new FilePath(buildDirectory));
         // TODO: switch to tar that preserves file permissions more easily
         if(!Functions.isWindows())
-            GNUCLibrary.LIBC.chmod(new File(mvnHome,mavenVersion+"/bin/mvn").getPath(),0755);
+            GNUCLibrary.LIBC.chmod(new File(mvnHome, "bin/mvn").getPath(),0755);
 
         MavenInstallation mavenInstallation = new MavenInstallation("default",
-                new File(mvnHome,mavenVersion).getAbsolutePath(), NO_PROPERTIES);
+                mvnHome.getAbsolutePath(), NO_PROPERTIES);
 		jenkins.getDescriptorByType(Maven.DescriptorImpl.class).setInstallations(mavenInstallation);
 		return mavenInstallation;
     }

test/src/main/java/org/jvnet/hudson/test/JenkinsRule.java

@@ -643,13 +643,10 @@ public void onOnline(Computer c, TaskListener listener) throws IOException, Inte
      */
     public Maven.MavenInstallation configureDefaultMaven(String mavenVersion, int mavenReqVersion) throws Exception {
         // first if we are running inside Maven, pick that Maven, if it meets the criteria we require..
-        // does it exists in the buildDirectory see maven-junit-plugin systemProperties
-        // buildDirectory -> ${project.build.directory} (so no reason to be null ;-) )
-        String buildDirectory = System.getProperty( "buildDirectory", "./target/classes/" );
-        File mavenAlreadyInstalled = new File(buildDirectory, mavenVersion);
-        if (mavenAlreadyInstalled.exists()) {
-            Maven.MavenInstallation
-                    mavenInstallation = new Maven.MavenInstallation("default",mavenAlreadyInstalled.getAbsolutePath(), NO_PROPERTIES);
+        File buildDirectory = new File(System.getProperty("buildDirectory", "target")); // TODO relative path
+        File mvnHome = new File(buildDirectory, mavenVersion);
+        if (mvnHome.exists()) {
+            Maven.MavenInstallation mavenInstallation = new Maven.MavenInstallation("default", mvnHome.getAbsolutePath(), NO_PROPERTIES);
             jenkins.getDescriptorByType(Maven.DescriptorImpl.class).setInstallations(mavenInstallation);
             return mavenInstallation;
         }
@@ -666,18 +663,17 @@ public void onOnline(Computer c, TaskListener listener) throws IOException, Inte
 
         // otherwise extract the copy we have.
         // this happens when a test is invoked from an IDE, for example.
-        LOGGER.warning("Extracting a copy of Maven bundled in the test harness. " +
+        LOGGER.warning("Extracting a copy of Maven bundled in the test harness into " + mvnHome + ". " +
                 "To avoid a performance hit, set the system property 'maven.home' to point to a Maven2 installation.");
         FilePath mvn = jenkins.getRootPath().createTempFile("maven", "zip");
         mvn.copyFrom(HudsonTestCase.class.getClassLoader().getResource(mavenVersion + "-bin.zip"));
-        File mvnHome =  new File(buildDirectory);//createTmpDir();
-        mvn.unzip(new FilePath(mvnHome));
+        mvn.unzip(new FilePath(buildDirectory));
         // TODO: switch to tar that preserves file permissions more easily
         if(!Functions.isWindows())
-            GNUCLibrary.LIBC.chmod(new File(mvnHome,mavenVersion+"/bin/mvn").getPath(),0755);
+            GNUCLibrary.LIBC.chmod(new File(mvnHome, "bin/mvn").getPath(),0755);
 
         Maven.MavenInstallation mavenInstallation = new Maven.MavenInstallation("default",
-                new File(mvnHome,mavenVersion).getAbsolutePath(), NO_PROPERTIES);
+                mvnHome.getAbsolutePath(), NO_PROPERTIES);
 		jenkins.getDescriptorByType(Maven.DescriptorImpl.class).setInstallations(mavenInstallation);
 		return mavenInstallation;
     }