Remove provider safety check and make all old ctx objects featureless

It's now allowed to return anything from a rule implementation function.
If a ctx object is returned it becomes featureless and cannot be used from
anywhere else (i.e. from an implementation function of another rule).

Fixes #2319

--
PiperOrigin-RevId: 151015919
MOS_MIGRATED_REVID=151015919

1 files changed, 5 insertions, 1 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
index bd0900b8a5..0c01e20c64 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkAspectFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkAspectFactory.java
@@ -51,10 +51,10 @@ public class SkylarkAspectFactory implements ConfiguredAspectFactory {
   public ConfiguredAspect create(
       ConfiguredTarget base, RuleContext ruleContext, AspectParameters parameters)
       throws InterruptedException {
+    SkylarkRuleContext skylarkRuleContext = null;
     try (Mutability mutability = Mutability.create("aspect")) {
       AspectDescriptor aspectDescriptor = new AspectDescriptor(
           skylarkAspect.getAspectClass(), parameters);
-      SkylarkRuleContext skylarkRuleContext;
       try {
         skylarkRuleContext = new SkylarkRuleContext(ruleContext, aspectDescriptor);
       } catch (EvalException e) {
@@ -94,6 +94,10 @@ public class SkylarkAspectFactory implements ConfiguredAspectFactory {
         ruleContext.ruleError("\n" + e.print());
         return null;
       }
+    } finally {
+       if (skylarkRuleContext != null) {
+         skylarkRuleContext.nullify();
+       }
     }
   }