| // Copyright 2020 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; |
| |
| import com.google.auto.value.AutoValue; |
| import com.google.common.base.Preconditions; |
| import com.google.devtools.build.lib.packages.AspectClass; |
| import com.google.devtools.build.lib.packages.Attribute; |
| import com.google.devtools.build.lib.packages.ExecGroup; |
| import javax.annotation.Nullable; |
| |
| /** |
| * A kind of dependency, used extensively in {@link DependencyResolver}. |
| * |
| * <p>Usually an attribute, but other special-cased kinds exist, for example, for visibility or |
| * toolchains. |
| */ |
| public interface DependencyKind { |
| /** A dependency for visibility. */ |
| DependencyKind VISIBILITY_DEPENDENCY = new NonAttributeDependencyKind("VISIBILITY"); |
| |
| /** The dependency on the rule that creates a given output file. */ |
| DependencyKind OUTPUT_FILE_RULE_DEPENDENCY = new NonAttributeDependencyKind("OUTPUT_FILE"); |
| |
| /** |
| * The attribute through which a dependency arises. |
| * |
| * <p>Returns {@code null} for visibility, the dependency pointing from an output file to its |
| * generating rule and toolchain dependencies. |
| */ |
| @Nullable |
| Attribute getAttribute(); |
| |
| /** |
| * The aspect owning the attribute through which the dependency arises. |
| * |
| * <p>Should only be called for dependency kinds representing an attribute. |
| */ |
| @Nullable |
| AspectClass getOwningAspect(); |
| |
| /** A dependency caused by something that's not an attribute. Special cases enumerated below. */ |
| final class NonAttributeDependencyKind implements DependencyKind { |
| private final String name; |
| |
| private NonAttributeDependencyKind(String name) { |
| this.name = name; |
| } |
| |
| @Nullable |
| @Override |
| public Attribute getAttribute() { |
| return null; |
| } |
| |
| @Nullable |
| @Override |
| public AspectClass getOwningAspect() { |
| throw new IllegalStateException(); |
| } |
| |
| @Override |
| public String toString() { |
| return String.format("%s(%s)", getClass().getSimpleName(), this.name); |
| } |
| } |
| |
| /** A dependency for a toolchain context, identified by the execution group name. */ |
| @AutoValue |
| abstract class ToolchainDependencyKind implements DependencyKind { |
| @Override |
| public Attribute getAttribute() { |
| return null; |
| } |
| |
| @Nullable |
| @Override |
| public AspectClass getOwningAspect() { |
| throw new IllegalStateException(); |
| } |
| |
| /** The name of the execution group represented by this dependency kind. */ |
| public abstract String getExecGroupName(); |
| |
| /** Returns true if this toolchain dependency is for the default exec group. */ |
| public abstract boolean isDefaultExecGroup(); |
| } |
| |
| /** Returns a {@link DependencyKind} for the given execution group. */ |
| static DependencyKind forExecGroup(String execGroupName) { |
| if (ExecGroup.DEFAULT_EXEC_GROUP_NAME.equals(execGroupName)) { |
| return defaultExecGroupToolchain(); |
| } |
| return new AutoValue_DependencyKind_ToolchainDependencyKind(execGroupName, false); |
| } |
| |
| /** Returns a {@link DependencyKind} for the default execution group. */ |
| static DependencyKind defaultExecGroupToolchain() { |
| return new AutoValue_DependencyKind_ToolchainDependencyKind( |
| ExecGroup.DEFAULT_EXEC_GROUP_NAME, true); |
| } |
| |
| /** Predicate to check if a dependency represents a toolchain. */ |
| static boolean isToolchain(DependencyKind dependencyKind) { |
| return dependencyKind instanceof ToolchainDependencyKind; |
| } |
| |
| /** A dependency through an attribute, either that of an aspect or the rule itself. */ |
| @AutoValue |
| abstract class AttributeDependencyKind implements DependencyKind { |
| @Override |
| public abstract Attribute getAttribute(); |
| |
| @Override |
| @Nullable |
| public abstract AspectClass getOwningAspect(); |
| |
| public static AttributeDependencyKind forRule(Attribute attribute) { |
| return new AutoValue_DependencyKind_AttributeDependencyKind(attribute, null); |
| } |
| |
| public static AttributeDependencyKind forAspect(Attribute attribute, AspectClass owningAspect) { |
| return new AutoValue_DependencyKind_AttributeDependencyKind( |
| attribute, Preconditions.checkNotNull(owningAspect)); |
| } |
| } |
| } |