1 files changed, 187 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
new file mode 100644
index 0000000000..f1aa2f6eba
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+++ b/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
@@ -0,0 +1,187 @@
+// Copyright 2014 Google Inc. 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.skyframe;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ListMultimap;
+import com.google.devtools.build.lib.analysis.Aspect;
+import com.google.devtools.build.lib.analysis.CachingAnalysisEnvironment;
+import com.google.devtools.build.lib.analysis.ConfiguredAspectFactory;
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTarget;
+import com.google.devtools.build.lib.analysis.TargetAndConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.ConfigMatchingProvider;
+import com.google.devtools.build.lib.events.StoredEventHandler;
+import com.google.devtools.build.lib.packages.AspectFactory;
+import com.google.devtools.build.lib.packages.Attribute;
+import com.google.devtools.build.lib.packages.NoSuchTargetException;
+import com.google.devtools.build.lib.packages.Rule;
+import com.google.devtools.build.lib.packages.Target;
+import com.google.devtools.build.lib.skyframe.AspectValue.AspectKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetFunction.DependencyEvaluationException;
+import com.google.devtools.build.lib.skyframe.SkyframeExecutor.BuildViewProvider;
+import com.google.devtools.build.skyframe.SkyFunction;
+import com.google.devtools.build.skyframe.SkyFunctionException;
+import com.google.devtools.build.skyframe.SkyKey;
+import com.google.devtools.build.skyframe.SkyValue;
+
+import java.util.Set;
+
+import javax.annotation.Nullable;
+
+/**
+ * The Skyframe function that generates aspects.
+ */
+public final class AspectFunction implements SkyFunction {
+  private final BuildViewProvider buildViewProvider;
+
+  public AspectFunction(BuildViewProvider buildViewProvider) {
+    this.buildViewProvider = buildViewProvider;
+  }
+
+  @Nullable
+  @Override
+  public SkyValue compute(SkyKey skyKey, Environment env)
+      throws AspectFunctionException {
+    SkyframeBuildView view = buildViewProvider.getSkyframeBuildView();
+    AspectKey key = (AspectKey) skyKey.argument();
+    ConfiguredAspectFactory aspectFactory =
+        (ConfiguredAspectFactory) AspectFactory.Util.create(key.getAspect());
+
+    PackageValue packageValue =
+        (PackageValue) env.getValue(PackageValue.key(key.getLabel().getPackageIdentifier()));
+    if (packageValue == null) {
+      return null;
+    }
+
+    Target target;
+    try {
+      target = packageValue.getPackage().getTarget(key.getLabel().getName());
+    } catch (NoSuchTargetException e) {
+      throw new AspectFunctionException(skyKey, e);
+    }
+
+    if (!(target instanceof Rule)) {
+      throw new AspectFunctionException(new AspectCreationException(
+          "aspects must be attached to rules"));
+    }
+
+    RuleConfiguredTarget associatedTarget = (RuleConfiguredTarget)
+        ((ConfiguredTargetValue) env.getValue(ConfiguredTargetValue.key(
+            key.getLabel(), key.getConfiguration()))).getConfiguredTarget();
+
+    if (associatedTarget == null) {
+      return null;
+    }
+
+    SkyframeDependencyResolver resolver = view.createDependencyResolver(env);
+    if (resolver == null) {
+      return null;
+    }
+
+    TargetAndConfiguration ctgValue =
+        new TargetAndConfiguration(target, key.getConfiguration());
+
+    try {
+      // Get the configuration targets that trigger this rule's configurable attributes.
+      Set<ConfigMatchingProvider> configConditions =
+          ConfiguredTargetFunction.getConfigConditions(target, env, resolver, ctgValue);
+      if (configConditions == null) {
+        // Those targets haven't yet been resolved.
+        return null;
+      }
+
+      ListMultimap<Attribute, ConfiguredTarget> depValueMap =
+          ConfiguredTargetFunction.computeDependencies(env, resolver, ctgValue,
+              aspectFactory.getDefinition(), configConditions);
+
+      return createAspect(env, key, associatedTarget, configConditions, depValueMap);
+    } catch (DependencyEvaluationException e) {
+      throw new AspectFunctionException(e.getRootCauseSkyKey(), e.getCause());
+    }
+  }
+
+  @Nullable
+  private AspectValue createAspect(Environment env, AspectKey key,
+      RuleConfiguredTarget associatedTarget, Set<ConfigMatchingProvider> configConditions,
+      ListMultimap<Attribute, ConfiguredTarget> directDeps)
+      throws AspectFunctionException {
+    SkyframeBuildView view = buildViewProvider.getSkyframeBuildView();
+    BuildConfiguration configuration = associatedTarget.getConfiguration();
+    boolean extendedSanityChecks = configuration != null && configuration.extendedSanityChecks();
+
+    StoredEventHandler events = new StoredEventHandler();
+    CachingAnalysisEnvironment analysisEnvironment = view.createAnalysisEnvironment(
+        key, false, extendedSanityChecks, events, env, true);
+    if (env.valuesMissing()) {
+      return null;
+    }
+
+    ConfiguredAspectFactory aspectFactory =
+        (ConfiguredAspectFactory) AspectFactory.Util.create(key.getAspect());
+    Aspect aspect = view.createAspect(
+        analysisEnvironment, associatedTarget, aspectFactory, directDeps, configConditions);
+
+    events.replayOn(env.getListener());
+    if (events.hasErrors()) {
+      analysisEnvironment.disable(associatedTarget.getTarget());
+      throw new AspectFunctionException(new AspectCreationException(
+          "Analysis of target '" + associatedTarget.getLabel() + "' failed; build aborted"));
+    }
+    Preconditions.checkState(!analysisEnvironment.hasErrors(),
+        "Analysis environment hasError() but no errors reported");
+
+    if (env.valuesMissing()) {
+      return null;
+    }
+
+    analysisEnvironment.disable(associatedTarget.getTarget());
+    Preconditions.checkNotNull(aspect);
+
+    return new AspectValue(
+        aspect, ImmutableList.copyOf(analysisEnvironment.getRegisteredActions()));
+  }
+
+  @Nullable
+  @Override
+  public String extractTag(SkyKey skyKey) {
+    return null;
+  }
+  
+  /**
+   * An exception indicating that there was a problem creating an aspect.
+   */
+  public static final class AspectCreationException extends Exception {
+    public AspectCreationException(String message) {
+      super(message);
+    }
+  }
+
+  /**
+   * Used to indicate errors during the computation of an {@link AspectValue}.
+   */
+  private static final class AspectFunctionException extends SkyFunctionException {
+    public AspectFunctionException(Exception e) {
+      super(e, Transience.PERSISTENT);
+    }
+
+    /** Used to rethrow a child error that we cannot handle. */
+    public AspectFunctionException(SkyKey childKey, Exception transitiveError) {
+      super(transitiveError, childKey);
+    }
+  }
+}