Implement aspect(...) Skylark function.

--
MOS_MIGRATED_REVID=105844221

1 files changed, 95 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkAspectFactory.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkAspectFactory.java
new file mode 100644
index 0000000000..d7bbf40ef9
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkAspectFactory.java
@@ -0,0 +1,95 @@
+// 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.skyframe;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.analysis.Aspect;
+import com.google.devtools.build.lib.analysis.ConfiguredAspectFactory;
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.events.Location;
+import com.google.devtools.build.lib.packages.AspectDefinition;
+import com.google.devtools.build.lib.packages.AspectParameters;
+import com.google.devtools.build.lib.rules.SkylarkRuleClassFunctions.SkylarkAspect;
+import com.google.devtools.build.lib.rules.SkylarkRuleContext;
+import com.google.devtools.build.lib.syntax.ClassObject.SkylarkClassObject;
+import com.google.devtools.build.lib.syntax.Environment;
+import com.google.devtools.build.lib.syntax.EvalException;
+import com.google.devtools.build.lib.syntax.Mutability;
+
+/**
+ * A factory for aspects that are defined in Skylark.
+ */
+public class SkylarkAspectFactory implements ConfiguredAspectFactory {
+
+  private final String name;
+  private final SkylarkAspect aspectFunction;
+
+  public SkylarkAspectFactory(String name, SkylarkAspect aspectFunction) {
+    this.name = name;
+    this.aspectFunction = aspectFunction;
+  }
+
+  @Override
+  public Aspect create(ConfiguredTarget base, RuleContext ruleContext, AspectParameters parameters)
+      throws InterruptedException {
+    try (Mutability mutability = Mutability.create("aspect")) {
+      SkylarkRuleContext skylarkRuleContext;
+      try {
+        skylarkRuleContext = new SkylarkRuleContext(ruleContext);
+      } catch (EvalException e) {
+        ruleContext.ruleError(e.getMessage());
+        return null;
+      }
+      Environment env =
+          Environment.builder(mutability)
+              .setSkylark()
+              .setGlobals(aspectFunction.getFuncallEnv().getGlobals())
+              .setEventHandler(ruleContext.getAnalysisEnvironment().getEventHandler())
+              .build(); // NB: loading phase functions are not available: this is analysis already,
+                        // so we do *not* setLoadingPhase().
+      Object aspect;
+      try {
+        aspect =
+            aspectFunction
+                .getImplementation()
+                .call(
+                    ImmutableList.<Object>of(base, skylarkRuleContext),
+                    ImmutableMap.<String, Object>of(),
+                    /*ast=*/ null,
+                    env);
+      } catch (EvalException e) {
+        ruleContext.ruleError(e.getMessage());
+        return null;
+      }
+      // TODO(dslomov): unify this code with
+      // {@link com.google.devtools.build.lib.rules.SkylarkRuleConfiguredTargetBuilder}
+      Aspect.Builder builder = new Aspect.Builder(name);
+      if (aspect instanceof SkylarkClassObject) {
+        SkylarkClassObject struct = (SkylarkClassObject) aspect;
+        Location loc = struct.getCreationLoc();
+        for (String key : struct.getKeys()) {
+          builder.addSkylarkTransitiveInfo(key, struct.getValue(key), loc);
+        }
+      }
+      return builder.build();
+    }
+  }
+
+  @Override
+  public AspectDefinition getDefinition() {
+    return new AspectDefinition.Builder(name).build();
+  }
+}