// Copyright 2016 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.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* A single dependency with its configured target and aspects merged together.
*
*
This is an ephemeral object created only for the analysis of a single configured target.
* After that configured target is analyzed, this is thrown away.
*/
public class MergedConfiguredTarget extends AbstractConfiguredTarget {
private final ConfiguredTarget base;
private final ImmutableMap, TransitiveInfoProvider>
providers;
private MergedConfiguredTarget(ConfiguredTarget base,
ImmutableMap, TransitiveInfoProvider> providers) {
super(base.getTarget(), base.getConfiguration());
this.base = base;
this.providers = providers;
}
/**
* Returns a value provided by this target. Only meant to use from Skylark.
*/
@Override
public Object get(String providerKey) {
return getProvider(SkylarkProviders.class).getValue(providerKey);
}
@Override
public P getProvider(Class
providerClass) {
AnalysisUtils.checkProvider(providerClass);
Object provider = providers.get(providerClass);
if (provider == null) {
provider = base.getProvider(providerClass);
}
return providerClass.cast(provider);
}
/**
* Creates an instance based on a configured target and a set of aspects.
*/
public static ConfiguredTarget of(ConfiguredTarget base,
Iterable aspects) {
if (Iterables.isEmpty(aspects)) {
// If there are no aspects, don't bother with creating a proxy object
return base;
}
Set> providers = new HashSet<>();
ImmutableSet> baseProviders =
ImmutableSet.copyOf(providers);
// Merge output group providers.
OutputGroupProvider mergedOutputGroupProvider =
OutputGroupProvider.merge(getAllProviders(base, aspects, OutputGroupProvider.class));
// Merge Skylark providers.
SkylarkProviders mergedSkylarkProviders =
SkylarkProviders.merge(getAllProviders(base, aspects, SkylarkProviders.class));
// Merge extra-actions provider.
ExtraActionArtifactsProvider mergedExtraActionProviders = ExtraActionArtifactsProvider.merge(
getAllProviders(base, aspects, ExtraActionArtifactsProvider.class));
Map, TransitiveInfoProvider> aspectProviders =
new LinkedHashMap<>();
if (mergedOutputGroupProvider != null) {
aspectProviders.put(OutputGroupProvider.class, mergedOutputGroupProvider);
}
if (mergedSkylarkProviders != null) {
aspectProviders.put(SkylarkProviders.class, mergedSkylarkProviders);
}
if (mergedExtraActionProviders != null) {
aspectProviders.put(ExtraActionArtifactsProvider.class, mergedExtraActionProviders);
}
for (ConfiguredAspect aspect : aspects) {
for (Map.Entry, TransitiveInfoProvider> entry :
aspect.getProviders().entrySet()) {
if (OutputGroupProvider.class.equals(entry.getKey())
|| SkylarkProviders.class.equals(entry.getKey())
|| ExtraActionArtifactsProvider.class.equals(entry.getKey())) {
continue;
}
if (base.getProvider(entry.getKey()) != null
|| aspectProviders.containsKey(entry.getKey())) {
throw new IllegalStateException("Provider " + entry.getKey() + " provided twice");
}
aspectProviders.put(entry.getKey(), entry.getValue());
}
}
return new MergedConfiguredTarget(base, ImmutableMap.copyOf(aspectProviders));
}
private static List getAllProviders(
ConfiguredTarget base, Iterable aspects, Class providerClass) {
T baseProvider = base.getProvider(providerClass);
List providers = new ArrayList<>();
if (baseProvider != null) {
providers.add(baseProvider);
}
for (ConfiguredAspect configuredAspect : aspects) {
final T aspectProvider = configuredAspect.getProvider(providerClass);
if (aspectProvider == null) {
continue;
}
providers.add(aspectProvider);
}
return providers;
}
}