Add 'aspect_id' for to identify aspects that has been applied to the target.

Add a concept of aspect_id: an unique string that identifies a
propagating aspect (aspect class + parameters).
This string is designed to be:
- Unique for each aspect
- human-readable for debugging purposes
- not easily parsable.

Skylark API:
- `ctx.aspect_id` returns an identifier of the current aspect inside
  aspect implementation    function
- `Target.aspect_ids` return a list of aspect ids for aspects applied to
  a given Target (https://www.bazel.io/versions/master/docs/skylark/lib/Target.html)

--
PiperOrigin-RevId: 141057865
MOS_MIGRATED_REVID=141057865

1 files changed, 5 insertions, 2 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 f078c3a154..2608c7f535 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
@@ -15,6 +15,7 @@ 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.AspectDescriptor;
 import com.google.devtools.build.lib.analysis.ConfiguredAspect;
 import com.google.devtools.build.lib.analysis.ConfiguredAspectFactory;
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
@@ -50,9 +51,11 @@ public class SkylarkAspectFactory implements ConfiguredAspectFactory {
       ConfiguredTarget base, RuleContext ruleContext, AspectParameters parameters)
       throws InterruptedException {
     try (Mutability mutability = Mutability.create("aspect")) {
+      AspectDescriptor aspectDescriptor = new AspectDescriptor(
+          skylarkAspect.getAspectClass(), parameters);
       SkylarkRuleContext skylarkRuleContext;
       try {
-        skylarkRuleContext = new SkylarkRuleContext(ruleContext, skylarkAspect);
+        skylarkRuleContext = new SkylarkRuleContext(ruleContext, aspectDescriptor);
       } catch (EvalException e) {
         ruleContext.ruleError(e.getMessage());
         return null;
@@ -82,7 +85,7 @@ public class SkylarkAspectFactory implements ConfiguredAspectFactory {
         }
 
         ConfiguredAspect.Builder builder = new ConfiguredAspect.Builder(
-            skylarkAspect.getAspectClass(), parameters, ruleContext);
+            aspectDescriptor, ruleContext);
 
         SkylarkClassObject struct = (SkylarkClassObject) aspectSkylarkObject;
         Location loc = struct.getCreationLoc();