message.append(parentId).append(" -> ");
                }
                message.append(parentData.id());

                problems.add(Severity.FATAL, ModelProblem.Version.BASE, message.toString());

                throw problems.newModelBuilderException();
            } else {
                currentData = parentData;
            }
        }

                                "Child module " + moduleFile + " of " + pomFile + " does not exist",
                                ModelProblem.Severity.ERROR,
                                ModelProblem.Version.BASE,
                                model,
                                -1,
                                -1,
                                null);
                        result.getProblems().add(problem);

    private boolean isValidProfileId(String id) {
        switch (id.charAt(0)) { // avoid first character that has special CLI meaning in "mvn -P xxx"
            case '+': // activate
            case '-': // deactivate
            case '!': // deactivate
            case '?': // optional
                return false;
            default:
        }
        return true;
    }

     * now depends upon d, which has a transitive dependency on c.  Even though
     * we did list an exclusion on c, it was only from within the context of
     * project b.  We will pick up project c in this case because no
     * restrictions were placed on d.  This demonstrates that a, b, c, & d will
     * all be collected.
     *
     * @throws Exception
     */
    @Test

import org.apache.maven.lifecycle.mapping.LifecycleMapping;
import org.apache.maven.lifecycle.mapping.LifecyclePhase;

import static java.util.Objects.requireNonNull;

/**
 * Base lifecycle mapping provider, ie per-packaging plugin bindings for {@code default} lifecycle.
 */
public abstract class AbstractLifecycleMappingProvider implements Provider<LifecycleMapping> {
    // START SNIPPET: versions