Merge pull request #532 from TheSnoozer/issues-531

#531: session.getProjectDependencyGraph() might be `null` when running the plugin from eclipse

Author: TheSnoozer

maven/src/main/java/pl/project13/maven/git/GitCommitIdMojo.java

@@ -68,25 +68,25 @@ public class GitCommitIdMojo extends AbstractMojo {
   /**
    * The list of projects in the reactor.
    */
-  @Parameter(defaultValue = "${reactorProjects}", readonly = true)
+  @Parameter(defaultValue = "${reactorProjects}", readonly = true, required = true)
   List<MavenProject> reactorProjects;
 
   /**
    * The Mojo Execution
    */
-  @Parameter(defaultValue = "${mojoExecution}", readonly = true)
+  @Parameter(defaultValue = "${mojoExecution}", readonly = true, required = true)
   MojoExecution mojoExecution;
 
   /**
    * The Maven Session Object.
    */
-  @Parameter(property = "session", required = true, readonly = true)
+  @Parameter(defaultValue = "${session}", readonly = true, required = true)
   MavenSession session;
 
   /**
    * The Maven settings.
    */
-  @Parameter(property = "settings", required = true, readonly = true)
+  @Parameter(defaultValue = "${settings}", readonly = true, required = true)
   Settings settings;
 
   /**
@@ -438,7 +438,13 @@ public void execute() throws MojoExecutionException {
       }
 
       if (runOnlyOnce) {
-        List<MavenProject> sortedProjects = session.getProjectDependencyGraph().getSortedProjects();
+        List<MavenProject> sortedProjects =
+                Optional.ofNullable(session.getProjectDependencyGraph())
+                        .map(graph -> graph.getSortedProjects())
+                        .orElseGet(() -> {
+                          log.warn("Maven's dependency graph is null. Assuming project is the only one executed.");
+                          return Collections.singletonList(session.getCurrentProject());
+                        });
         MavenProject firstProject = sortedProjects.stream()
                 // skipPoms == true => find first project that is not pom project
                 .filter(p -> {