// it's all encapsulated here so it appears normalized to the POM builder.

    // We are going to take the project packaging and find all plugin in the default lifecycle and create
    // fully populated Plugin objects, including executions with goals and default configuration taken
    // from the plugin.xml inside a plugin.
    //

    }
  }

  /**
   * Returns the identity function.
   *
   * <p><b>Discouraged:</b> Prefer using a lambda like {@code v -> v}, which is shorter and often
   * more readable.
   */
  // implementation is "fully variant"; E has become a "pass-through" type
  @SuppressWarnings("unchecked")
  public static <E extends @Nullable Object> Function<E, E> identity() {
    return (Function<E, E>) IdentityFunction.INSTANCE;
  }

      this.wrapped = checkNotNull(wrapped);
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      // In general getClass().isInstance() is bad for equals.
      // But here we fully control the subclasses to ensure symmetry.
      if (getClass().isInstance(obj)) {
        Wrapper that = (Wrapper) obj;
        return wrapped.equals(that.wrapped);
      }
      return false;
    }

                extensionRecord = setupExtensionsRealm(project, plugin, repositorySession);
            } catch (PluginManagerException e) {
                // extensions realm is expected to be fully setup at this point
                // any exception means a problem in maven code, not a user error
                throw new IllegalStateException(e);
            }

        // url normalization
        resultModel = modelUrlNormalizer.normalize(resultModel, request);

        result.setEffectiveModel(resultModel);

        // Now the fully interpolated model is available: reconfigure the resolver
        if (!resultModel.getRepositories().isEmpty()) {
            List<String> oldRepos = request.getModelRepositoryHolder().getRepositories().stream()

    // it's all encapsulated here so it appears normalized to the POM builder.

    // We are going to take the project packaging and find all plugins in the default lifecycle and create
    // fully populated Plugin objects, including executions with goals and default configuration taken
    // from the plugin.xml inside a plugin.
    //

    @Override

          assertThat(b).isNotEqualTo(0);
        } catch (ArithmeticException e) {
          assertThat(b).isEqualTo(0);
        }
      }
    }
  }

  @GwtIncompatible // Too slow in GWT (~3min fully optimized)
  public void testDivideRemainderEuclideanProperty() {
    // Use a seed so that the test is deterministic:
    Random r = new Random(0L);
    for (int i = 0; i < 1000000; i++) {

   *
   * @since 8.0
   */
  public static <T extends @Nullable Object> Function<Supplier<T>, T> supplierFunction() {
    @SuppressWarnings("unchecked") // implementation is "fully variant"
    SupplierFunction<T> sf = (SupplierFunction<T>) SupplierFunctionImpl.INSTANCE;
    return sf;
  }

  private interface SupplierFunction<T extends @Nullable Object> extends Function<Supplier<T>, T> {}

     */
    void validateRawModel(Model model, ModelBuilderRequest request, ModelProblemCollector problems);

    /**
     * Checks the specified (effective) model for missing or invalid values. The effective model is fully assembled and
     * has undergone inheritance, interpolation and other model operations.
     *
     * @param model The model to validate, must not be {@code null}.

            throws IOException;

    /**
     * Calculates checksums for specified stream. Upon this method returns, the stream will be depleted (fully read)
     * but not closed.
     *
     * @param stream      The stream for which to calculate checksums, must not be {@code null}.
     * @param algorithms  The checksum algorithms to use, must not be {@code null}.