commit 459f1300ff234da7d79b1887bd08edb734f79970
author Googler <noreply@google.com> Wed Apr 05 19:40:35 2017 +0000
committer Marcel Hlopko <hlopko@google.com> Thu Apr 06 11:00:27 2017 +0200
tree 9dcee2da1f3f102298b583bab190facbce02786d
parent d119f969a30945a1fc29a24a293f6873ff73960d

Add mechanism to trigger Python type-stripping via a tag.

RELNOTES: none

PiperOrigin-RevId: 152291766

src/main/java/com/google/devtools/build/lib/packages/Attribute.java

diff --git a/src/main/java/com/google/devtools/build/lib/packages/Attribute.java b/src/main/java/com/google/devtools/build/lib/packages/Attribute.java
index 8751696..ca9547f 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/Attribute.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/Attribute.java
@@ -104,7 +104,8 @@
 
     @Override
     public Aspect getAspect(Rule rule) {
-      return Aspect.forNative(aspectClass, parametersExtractor.apply(rule));
+      AspectParameters params = parametersExtractor.apply(rule);
+      return params == null ? null : Aspect.forNative(aspectClass, params);
     }
   }
 
@@ -992,7 +993,8 @@
      * Asserts that a particular parameterized aspect probably needs to be computed for all direct
      * dependencies through this attribute.
      *
-     * @param evaluator function that extracts aspect parameters from rule.
+     * @param evaluator function that extracts aspect parameters from rule. If it returns null,
+     * then the aspect will not be attached.
      */
     public Builder<TYPE> aspect(
         NativeAspectClass aspect, Function<Rule, AspectParameters> evaluator) {
@@ -2050,7 +2052,10 @@
   public ImmutableList<Aspect> getAspects(Rule rule) {
     ImmutableList.Builder<Aspect> builder = ImmutableList.builder();
     for (RuleAspect aspect : aspects) {
-      builder.add(aspect.getAspect(rule));
+      Aspect a = aspect.getAspect(rule);
+      if (a != null) {
+        builder.add(a);
+      }
     }
     return builder.build();
   }