Fix aggregating mojos (#174)

Changes:
* parent-child-tree made aggregator
* subproject-tree made agregator
* project-dependency-tree made aggregator

Former two should be run from same spot from where you'd invoke 'full build', while latter allows targeting project using `-Dselector=` where value may be `:A`, `:A:V`, `G:A` or `G:A:V`. Selector must match exactly 1 project, otherwise (0 or 2+ matches) it will fail.

Author: cstamas

toolbox/src/main/java/eu/maveniverse/maven/toolbox/plugin/MPMojoSupport.java

@@ -105,7 +105,7 @@ protected boolean isReactorDependency(Dependency dependency) {
                                 p.getVersion(), dependency.getArtifact().getVersion()));
     }
 
-    protected ReactorLocator getReactorLocator() {
-        return new MavenReactorLocator(mavenSession);
+    protected ReactorLocator getReactorLocator(String selector) {
+        return new MavenReactorLocator(mavenSession, selector);
     }
 }

toolbox/src/main/java/eu/maveniverse/maven/toolbox/plugin/MavenReactorLocator.java

@@ -11,9 +11,11 @@
 
 import eu.maveniverse.maven.toolbox.shared.ProjectLocator;
 import eu.maveniverse.maven.toolbox.shared.ReactorLocator;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import org.apache.maven.RepositoryUtils;
@@ -34,17 +36,55 @@ public class MavenReactorLocator implements ReactorLocator {
     private final Project current;
     private final List<Project> allProjects;
 
-    public MavenReactorLocator(MavenSession session) {
+    public MavenReactorLocator(MavenSession session, String selector) {
         requireNonNull(session, "session");
         this.allProjects = session.getAllProjects().stream()
                 .map(p -> convert(session.getRepositorySession(), p))
                 .collect(Collectors.toList());
         this.topLevel = locateProject(
                         RepositoryUtils.toArtifact(session.getTopLevelProject().getArtifact()))
                 .orElseThrow();
-        this.current = locateProject(
-                        RepositoryUtils.toArtifact(session.getCurrentProject().getArtifact()))
-                .orElseThrow();
+        if (selector != null) {
+            List<MavenProject> candidates = session.getAllProjects().stream()
+                    .filter(createSelector(selector))
+                    .collect(Collectors.toList());
+            if (candidates.size() != 1) {
+                List<String> matches = candidates.stream()
+                        .map(p -> ArtifactIdUtils.toId(RepositoryUtils.toArtifact(p.getArtifact())))
+                        .collect(Collectors.toList());
+                throw new IllegalArgumentException("Could not find 1 matching project: " + matches);
+            }
+            this.current = locateProject(
+                            RepositoryUtils.toArtifact(candidates.get(0).getArtifact()))
+                    .orElseThrow();
+        } else {
+            this.current = locateProject(RepositoryUtils.toArtifact(
+                            session.getCurrentProject().getArtifact()))
+                    .orElseThrow();
+        }
+    }
+
+    private Predicate<MavenProject> createSelector(String selector) {
+        String[] elems =
+                Arrays.stream(selector.split(":", -1)).filter(s -> !s.isEmpty()).toArray(String[]::new);
+        if (selector.startsWith(":")) {
+            // :A or :A:V
+            if (elems.length == 1) {
+                return p -> p.getArtifactId().equals(elems[0]);
+            } else if (elems.length == 2) {
+                return p -> p.getArtifactId().equals(elems[0]) && p.getVersion().equals(elems[1]);
+            }
+        } else {
+            // G:A or G:A:V
+            if (elems.length == 2) {
+                return p -> p.getGroupId().equals(elems[0]) && p.getArtifactId().equals(elems[1]);
+            } else if (elems.length == 3) {
+                return p -> p.getGroupId().equals(elems[0])
+                        && p.getArtifactId().equals(elems[1])
+                        && p.getVersion().equals(elems[2]);
+            }
+        }
+        throw new IllegalArgumentException("Unsupported selector expression: '" + selector + "'");
     }
 
     private Project convert(RepositorySystemSession session, MavenProject project) {

toolbox/src/main/java/eu/maveniverse/maven/toolbox/plugin/mp/ParentChildTreeMojo.java

@@ -10,15 +10,24 @@
 import eu.maveniverse.maven.toolbox.plugin.MPMojoSupport;
 import eu.maveniverse.maven.toolbox.shared.Result;
 import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.Parameter;
 import org.eclipse.aether.collection.CollectResult;
 
 /**
  * Displays project inheritance of Maven Projects.
  */
-@Mojo(name = "parent-child-tree", threadSafe = true)
+@Mojo(name = "parent-child-tree", aggregator = true, threadSafe = true)
 public class ParentChildTreeMojo extends MPMojoSupport {
+    /**
+     * Set the project selector, like {@code -rf} Maven command uses it, can be {@code :A} or {@code G:A}. If the
+     * selector is set, it must match exactly one project within reactor, otherwise it will fail. By default,
+     * selector is {@code null}, and Maven session "current project" is used.
+     */
+    @Parameter(property = "selector")
+    private String selector;
+
     @Override
     protected Result<CollectResult> doExecute() throws Exception {
-        return getToolboxCommando().parentChildTree(getReactorLocator());
+        return getToolboxCommando().parentChildTree(getReactorLocator(selector));
     }
 }

toolbox/src/main/java/eu/maveniverse/maven/toolbox/plugin/mp/ProjectDependencyTreeMojo.java

@@ -16,7 +16,7 @@
 /**
  * Displays project interdependencies of Maven Projects.
  */
-@Mojo(name = "project-dependency-tree", threadSafe = true)
+@Mojo(name = "project-dependency-tree", aggregator = true, threadSafe = true)
 public class ProjectDependencyTreeMojo extends MPMojoSupport {
 
     /**
@@ -25,8 +25,16 @@ public class ProjectDependencyTreeMojo extends MPMojoSupport {
     @Parameter(property = "showExternal", defaultValue = "false", required = true)
     private boolean showExternal;
 
+    /**
+     * Set the project selector, like {@code -rf} Maven command uses it, can be {@code :A} or {@code G:A}. If the
+     * selector is set, it must match exactly one project within reactor, otherwise it will fail. By default,
+     * selector is {@code null}, and Maven session "current project" is used.
+     */
+    @Parameter(property = "selector")
+    private String selector;
+
     @Override
     protected Result<CollectResult> doExecute() throws Exception {
-        return getToolboxCommando().projectDependencyTree(getReactorLocator(), showExternal);
+        return getToolboxCommando().projectDependencyTree(getReactorLocator(selector), showExternal);
     }
 }

toolbox/src/main/java/eu/maveniverse/maven/toolbox/plugin/mp/SubprojectTreeMojo.java

@@ -10,15 +10,24 @@
 import eu.maveniverse.maven.toolbox.plugin.MPMojoSupport;
 import eu.maveniverse.maven.toolbox.shared.Result;
 import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.Parameter;
 import org.eclipse.aether.collection.CollectResult;
 
 /**
  * Displays subproject collection of Maven Projects.
  */
-@Mojo(name = "subproject-tree", threadSafe = true)
+@Mojo(name = "subproject-tree", aggregator = true, threadSafe = true)
 public class SubprojectTreeMojo extends MPMojoSupport {
+    /**
+     * Set the project selector, like {@code -rf} Maven command uses it, can be {@code :A} or {@code G:A}. If the
+     * selector is set, it must match exactly one project within reactor, otherwise it will fail. By default,
+     * selector is {@code null}, and Maven session "current project" is used.
+     */
+    @Parameter(property = "selector")
+    private String selector;
+
     @Override
     protected Result<CollectResult> doExecute() throws Exception {
-        return getToolboxCommando().subprojectTree(getReactorLocator());
+        return getToolboxCommando().subprojectTree(getReactorLocator(selector));
     }
 }