plugin = (Plugin) data;
            }
            trace = trace.getParent();
        }

        Path trackingDir;
        boolean missing = event.getFile() == null;
        if (missing) {
            // missing artifact - let's track the path anyway
            File dir = event.getSession().getLocalRepository().getBasedir();
            dir = new File(

  <groupId>markerTest</groupId>
  <artifactId>testArtifactMissingVersion</artifactId>
  <version>0.0.1-SNAPSHOT</version>

  <dependencies>
    <dependency>
      <groupId>missing</groupId>
      <artifactId>missing</artifactId>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>2.0.2</version>
      </plugin>

            protected ActivationFile.Builder transformActivationFile_Missing(
                    Supplier<? extends ActivationFile.Builder> creator,
                    ActivationFile.Builder builder,
                    ActivationFile target) {
                String path = target.getMissing();
                String xformed = transformPath(path, target, "missing");

            //
            // idea:idea
            //
            String prefix = tok[0];

            if (numTokens == 2) {
                goal = tok[1];
            } else {
                // goal was missing - pass through to MojoNotFoundException
                goal = "";
            }

            // This is the case where someone has executed a single goal from the command line
            // of the form:

  <version>1.0</version>
  <packaging>jar</packaging>

  <name>Maven Integration Test :: it0052</name>
  <description>Test that source attachment doesn't take place when -DperformRelease=true is missing.</description>

  <!-- NOTE: Use stub versions of the core plugins referenced by the build -->
  <build>
    <pluginManagement>
      <plugins>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>

        }
    }

    @Override
    public void artifactDescriptorMissing(RepositoryEvent event) {
        logger.warn("The POM for {} is missing, no dependency information available", event.getArtifact());
    }

        // execute
        ToolchainPrivate[] toolchains = toolchainManager.getToolchainsForType("unknown", session);

        // verify
        verify(logger).error("Missing toolchain factory for type: unknown. Possibly caused by misconfigured project.");
        assertEquals(0, toolchains.length);
    }

    @Test
    void testToolchainsForConfiguredType() throws Exception {

        List<Toolchain> toolchains = toolchainManager.getToolchains(session, "unknown", null);

        assertEquals(0, toolchains.size());
        verify(logger).error("Missing toolchain factory for type: unknown. Possibly caused by misconfigured project.");
    }

    @Test
    void testModelAndFactory() {
        MavenSession session = mock(MavenSession.class);

            if (id == null || id.isEmpty()) {
                throw new InvalidRepositoryException("Repository identifier missing", "");
            }

            String url = repo.getUrl();

            if (url == null || url.isEmpty()) {
                throw new InvalidRepositoryException("URL missing for repository " + id, id);
            }

                PrintStream ps = new PrintStream(os);
                ps.println("Unable to load the mojo '" + mojoDescriptor.getGoal() + "' in the plugin '"
                        + pluginDescriptor.getId() + "'. A required class is missing: "
                        + cause.getMessage());
                pluginRealm.display(ps);

                throw new PluginContainerException(mojoDescriptor, pluginRealm, os.toString(), cause);