blob: c584db114d8cc41a6d81f680c8cc67a4867408e0 [file] [log] [blame]
// Copyright 2014 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.common.base.Preconditions;
import com.google.common.base.Predicate;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.collect.nestedset.NestedSet;
import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
import com.google.devtools.build.lib.util.FileType;
import com.google.devtools.build.lib.util.FileTypeSet;
/**
* Contains a sequence of prerequisite artifacts and supplies methods for filtering and reporting
* errors on those artifacts.
*/
public final class PrerequisiteArtifacts {
private final RuleContext ruleContext;
private final String attributeName;
private final ImmutableList<Artifact> artifacts;
private PrerequisiteArtifacts(
RuleContext ruleContext, String attributeName, ImmutableList<Artifact> artifacts) {
this.ruleContext = Preconditions.checkNotNull(ruleContext);
this.attributeName = Preconditions.checkNotNull(attributeName);
this.artifacts = Preconditions.checkNotNull(artifacts);
}
static PrerequisiteArtifacts get(RuleContext ruleContext, String attributeName) {
ImmutableList<FileProvider> prerequisites =
ImmutableList.copyOf(ruleContext.getPrerequisites(attributeName, FileProvider.class));
// Fast path #1: Many attributes are not set.
if (prerequisites.isEmpty()) {
return new PrerequisiteArtifacts(ruleContext, attributeName, ImmutableList.of());
}
// Fast path #2: Often, attributes are set exactly once. In this case, we can completely elide
// additional copies as the getFilesToBuild() call already returns an ImmutableList of the
// expanded NestedSet.
if (prerequisites.size() == 1) {
return new PrerequisiteArtifacts(
ruleContext, attributeName, prerequisites.get(0).getFilesToBuild().toList());
}
ImmutableSet.Builder<Artifact> result = ImmutableSet.builder();
for (FileProvider target : prerequisites) {
result.addAll(target.getFilesToBuild().toList());
}
return new PrerequisiteArtifacts(ruleContext, attributeName, result.build().asList());
}
public static NestedSet<Artifact> nestedSet(RuleContext ruleContext, String attributeName) {
NestedSetBuilder<Artifact> result = NestedSetBuilder.stableOrder();
for (FileProvider target : ruleContext.getPrerequisites(attributeName, FileProvider.class)) {
result.addTransitive(target.getFilesToBuild());
}
return result.build();
}
/**
* Returns the artifacts this instance contains in an {@link ImmutableList}.
*/
public ImmutableList<Artifact> list() {
return artifacts;
}
private PrerequisiteArtifacts filter(Predicate<String> fileType, boolean errorsForNonMatching) {
ImmutableList.Builder<Artifact> filtered = new ImmutableList.Builder<>();
for (Artifact artifact : artifacts) {
if (fileType.apply(artifact.getFilename())) {
filtered.add(artifact);
} else if (errorsForNonMatching) {
ruleContext.attributeError(
attributeName,
String.format("%s does not match expected type: %s", artifact, fileType));
}
}
return new PrerequisiteArtifacts(ruleContext, attributeName, filtered.build());
}
/** Returns an equivalent instance but only containing artifacts of the given type. */
public PrerequisiteArtifacts filter(FileType fileType) {
return filter(fileType, /*errorsForNonMatching=*/ false);
}
/** Returns an equivalent instance but only containing artifacts of the given types. */
public PrerequisiteArtifacts filter(FileTypeSet fileTypeSet) {
return filter(fileTypeSet, /*errorsForNonMatching=*/ false);
}
/**
* Returns an equivalent instance but only containing artifacts of the given type, reporting
* errors for non-matching artifacts.
*/
public PrerequisiteArtifacts errorsForNonMatching(FileType fileType) {
return filter(fileType, /*errorsForNonMatching=*/true);
}
/**
* Returns an equivalent instance but only containing artifacts of the given types, reporting
* errors for non-matching artifacts.
*/
public PrerequisiteArtifacts errorsForNonMatching(FileTypeSet fileTypeSet) {
return filter(fileTypeSet, /*errorsForNonMatching=*/true);
}
}