| // Copyright 2019 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| package com.google.devtools.build.lib.analysis.skylark; |
| |
| import com.google.devtools.build.lib.analysis.config.StarlarkDefinedConfigTransition; |
| import com.google.devtools.build.lib.analysis.config.transitions.ComposingTransition; |
| import com.google.devtools.build.lib.analysis.config.transitions.ConfigurationTransition; |
| import com.google.devtools.build.lib.events.ExtendedEventHandler; |
| import java.util.List; |
| import java.util.Objects; |
| |
| /** A marker class for configuration transitions that are defined in Starlark. */ |
| public abstract class StarlarkTransition implements ConfigurationTransition { |
| |
| private final StarlarkDefinedConfigTransition starlarkDefinedConfigTransition; |
| |
| public StarlarkTransition(StarlarkDefinedConfigTransition starlarkDefinedConfigTransition) { |
| this.starlarkDefinedConfigTransition = starlarkDefinedConfigTransition; |
| } |
| |
| public void replayOn(ExtendedEventHandler eventHandler) { |
| starlarkDefinedConfigTransition.getEventHandler().replayOn(eventHandler); |
| starlarkDefinedConfigTransition.getEventHandler().clear(); |
| } |
| |
| public boolean hasErrors() { |
| return starlarkDefinedConfigTransition.getEventHandler().hasErrors(); |
| } |
| |
| /** Exception class for exceptions thrown during application of a starlark-defined transition */ |
| public static class TransitionException extends Exception { |
| public TransitionException(String message) { |
| super(message); |
| } |
| } |
| |
| /** |
| * Method to be called after Starlark-transitions are applied. Logs any events (e.g. {@code |
| * print()}s, errors} to output and throws an error if we had any errors. Right now, Starlark |
| * transitions are the only kind that knows how to throw errors so we know this will only report |
| * and throw if a Starlark transition caused a problem. |
| * |
| * @param eventHandler eventHandler to replay events on |
| * @param root transition that was applied. Could be a composing transition so we pull and |
| * post-process all StarlarkTransitions out of whatever transition is passed here |
| * @throws TransitionException if an error occurred during Starlark transition application. |
| */ |
| public static void postProcessStarlarkTransitions( |
| ExtendedEventHandler eventHandler, ConfigurationTransition root) throws TransitionException { |
| List<ConfigurationTransition> transitions = ComposingTransition.decomposeTransition(root); |
| for (ConfigurationTransition transition : transitions) { |
| if (transition instanceof StarlarkTransition) { |
| StarlarkTransition starlarkTransition = (StarlarkTransition) transition; |
| boolean hasErrors = starlarkTransition.hasErrors(); |
| starlarkTransition.replayOn(eventHandler); |
| if (hasErrors) { |
| throw new TransitionException("Errors encountered while applying Starlark transition"); |
| } |
| } |
| } |
| } |
| |
| @Override |
| public boolean equals(Object object) { |
| if (object == this) { |
| return true; |
| } |
| if (object instanceof StarlarkTransition) { |
| StarlarkDefinedConfigTransition starlarkDefinedConfigTransition = |
| ((StarlarkTransition) object).starlarkDefinedConfigTransition; |
| return Objects.equals(starlarkDefinedConfigTransition, this.starlarkDefinedConfigTransition); |
| } |
| return false; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hashCode(starlarkDefinedConfigTransition); |
| } |
| } |