[MINVOKER-336] Create empty .mvn directory in cloned projects

Author: slawekjaranowski

src/it/clone-clean/verify.bsh renamed to src/it/clone-clean/setup.groovy

@@ -17,15 +17,9 @@
  * under the License.
  */
 
-import java.io.*;
+File itRoot = new File(basedir, "target/it/clone-clean")
+itRoot.mkdirs()
+assert new File(itRoot, "foobar.log").createNewFile()
+
+assert !new File(basedir, 'src/it/clone-clean/.mvn').exists()
 
-try
-{
-    File itRoot = new File( basedir, "target/it/clone-clean" );
-    return !new File( itRoot, "foobar.log" ).exists();
-}
-catch( Throwable t )
-{
-    t.printStackTrace();
-    return false;
-}

src/it/clone-clean/setup.bsh renamed to src/it/clone-clean/verify.groovy

@@ -17,16 +17,8 @@
  * under the License.
  */
 
-import java.io.*;
 
-try
-{
-    File itRoot = new File( basedir, "target/it/clone-clean" );
-    itRoot.mkdirs();
-    return new File(itRoot, "foobar.log").createNewFile();
-}
-catch( Throwable t )
-{
-    t.printStackTrace();
-    return false;
-}
+File itRoot = new File(basedir, "target/it/clone-clean")
+assert !new File(itRoot, "foobar.log").exists()
+// .mnv will be created
+assert new File(itRoot, ".mvn").isDirectory()

src/main/java/org/apache/maven/plugins/invoker/AbstractInvokerMojo.java

@@ -820,6 +820,7 @@ public void execute() throws MojoExecutionException, MojoFailureException {
 
         if (cloneProjectsTo != null) {
             cloneProjects(collectedProjects);
+            addMissingDotMvnDirectory(cloneProjectsTo, buildJobs);
             projectsDir = cloneProjectsTo;
         } else {
             getLog().warn("Filtering of parent/child POMs is not supported without cloning the projects");
@@ -856,6 +857,31 @@ public void execute() throws MojoExecutionException, MojoFailureException {
         processResults(new InvokerSession(buildJobs));
     }
 
+    /**
+     * We need add missing {@code .mnvn} directories for executing projects
+     *
+     * @param projectsDir base of projects
+     * @param buildJobs list of discovered jobs
+     */
+    private void addMissingDotMvnDirectory(File projectsDir, List<BuildJob> buildJobs) throws MojoExecutionException {
+        for (BuildJob buildJob : buildJobs) {
+            Path projectPath = projectsDir.toPath().resolve(buildJob.getProject());
+
+            if (Files.isRegularFile(projectPath)) {
+                projectPath = projectPath.getParent();
+            }
+
+            Path mvnDotPath = projectPath.resolve(".mvn");
+            if (!Files.exists(mvnDotPath)) {
+                try {
+                    Files.createDirectories(mvnDotPath);
+                } catch (IOException e) {
+                    throw new MojoExecutionException(e.getMessage(), e);
+                }
+            }
+        }
+    }
+
     private void setupActualMavenVersion() throws MojoExecutionException {
         if (mavenHome != null) {
             try {