| // Copyright 2017 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.config; |
| |
| import com.google.common.collect.Iterables; |
| import com.google.devtools.build.lib.analysis.config.transitions.ConfigurationTransition; |
| import com.google.devtools.build.lib.analysis.config.transitions.PatchTransition; |
| import com.google.devtools.build.lib.packages.Rule; |
| import com.google.devtools.build.lib.packages.RuleTransitionFactory; |
| import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec; |
| |
| /** A {@link RuleTransitionFactory} that composes other {@link RuleTransitionFactory}s. */ |
| @AutoCodec |
| public class ComposingRuleTransitionFactory implements RuleTransitionFactory { |
| |
| private final RuleTransitionFactory rtf1; |
| private final RuleTransitionFactory rtf2; |
| |
| /** |
| * Creates a factory that applies the given factories in-order ({@code rtf1} first, |
| * {@code rtf2} second). |
| */ |
| public ComposingRuleTransitionFactory(RuleTransitionFactory rtf1, RuleTransitionFactory rtf2) { |
| this.rtf1 = rtf1; |
| this.rtf2 = rtf2; |
| } |
| |
| @Override |
| public PatchTransition buildTransitionFor(Rule rule) { |
| ConfigurationTransition composed = TransitionResolver.composeTransitions( |
| rtf1.buildTransitionFor(rule), rtf2.buildTransitionFor(rule)); |
| if (composed instanceof PatchTransition) { |
| // This is one of the two input transitions. Especially if it's a NoTransition or |
| // HostTransition, we should give it back so it can be specially identified as described |
| // in composeTransitions. |
| return (PatchTransition) composed; |
| } else { |
| // This is a composed transition, but we need a composed transition which is both a |
| // PatchTransition and can be registered as equal to another instance of the same composed |
| // transition. |
| return new AsPatchTransition(composed); |
| } |
| } |
| |
| private static final class AsPatchTransition implements PatchTransition { |
| private final ConfigurationTransition wrapped; |
| |
| private AsPatchTransition(ConfigurationTransition wrapped) { |
| this.wrapped = wrapped; |
| } |
| |
| @Override |
| public BuildOptions patch(BuildOptions options) { |
| return Iterables.getOnlyElement(wrapped.apply(options)); |
| } |
| |
| @Override |
| public int hashCode() { |
| return wrapped.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object other) { |
| return other instanceof AsPatchTransition |
| && this.wrapped.equals(((AsPatchTransition) other).wrapped); |
| } |
| } |
| } |