From 34c5ef22e88eba60238ad3735b74ea71db1c993e Mon Sep 17 00:00:00 2001
From: Googler <noreply@google.com>
Date: Tue, 22 Aug 2023 16:14:09 -0700
Subject: [PATCH] make sure IdempotencyChecker use the correct rule transition
 and remove redundant computeTransition calls.

PiperOrigin-RevId: 559252770
Change-Id: Iab6c893c25aae081ff35407c6650b12bdd214607
---
 .../TargetAndConfigurationProducer.java       | 39 +++++++++----------
 1 file changed, 18 insertions(+), 21 deletions(-)

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/TargetAndConfigurationProducer.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/TargetAndConfigurationProducer.java
index fbd2579cc2e75d..6e554aca213bf2 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/TargetAndConfigurationProducer.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/TargetAndConfigurationProducer.java
@@ -229,14 +229,7 @@ private StateMachine determineConfiguration(Tasks tasks) {
       return DONE;
     }
 
-    ConfigurationTransition transition =
-        computeTransition(target.getAssociatedRule(), trimmingTransitionFactory);
-    if (transition == null) {
-      lookUpConfigurationValue(tasks);
-      return DONE;
-    }
-
-    return new RuleTransitionApplier(transition);
+    return new RuleTransitionApplier();
   }
 
   private void delegateTo(Tasks tasks, ActionLookupKey delegate) {
@@ -274,19 +267,12 @@ private class RuleTransitionApplier
           TransitionApplier.ResultSink,
           ConfigConditionsProducer.ResultSink,
           PlatformInfoProducer.ResultSink {
-    // -------------------- Input --------------------
-    private final ConfigurationTransition transition;
     // -------------------- Internal State --------------------
-    private BuildConfigurationKey configurationKey;
-
-    private RuleTransitionApplier(ConfigurationTransition transition) {
-      this.transition = transition;
-    }
-
-    private ConfigConditions configConditions;
-
     @Nullable private PlatformInfo platformInfo;
-
+    private ConfigConditions configConditions;
+    private ConfigurationTransition ruleTransition;
+    private BuildConfigurationKey configurationKey;
+        
     @Override
     public StateMachine step(Tasks tasks) throws InterruptedException {
 
@@ -316,6 +302,7 @@ public StateMachine step(Tasks tasks) throws InterruptedException {
       return DONE;
     }
 
+    // TODO: @aranguyen b/297077082
     public UnloadedToolchainContextsInputs getUnloadedToolchainContextsInputs(
         Target target, @Nullable Label parentExecutionPlatformLabel) throws InterruptedException {
       if (!(target instanceof Rule)) {
@@ -450,6 +437,7 @@ private ImmutableSet<Label> getExecutionPlatformConstraints(
 
     @CanIgnoreReturnValue
     public StateMachine computeConfigConditions(Tasks tasks) {
+      // TODO @aranguyen b/297077082
       tasks.enqueue(
           new ConfigConditionsProducer(
               target,
@@ -488,9 +476,17 @@ public StateMachine computeTransition(Tasks tasks) {
           transition = trimmingTransition;
         }
       }
+
+      if (transition == null) {
+        lookUpConfigurationValue(tasks);
+        return DONE;
+      }
+
+      this.ruleTransition = transition;
+
       return new TransitionApplier(
           preRuleTransitionKey.getConfigurationKey(),
-          transition,
+          ruleTransition,
           transitionCache,
           (TransitionApplier.ResultSink) this,
           eventHandler,
@@ -592,7 +588,7 @@ private class IdempotencyChecker implements StateMachine, TransitionApplier.Resu
       public StateMachine step(Tasks tasks) {
         return new TransitionApplier(
             configurationKey,
-            transition,
+            ruleTransition,
             transitionCache,
             (TransitionApplier.ResultSink) this,
             eventHandler,
@@ -683,6 +679,7 @@ public static DetailedExitCode createDetailedExitCode(String message) {
   }
 
   // Public for Cquery.
+  // TODO: @aranguyen keep cquery in sync with ConfiguredTargetFunction
   @Nullable
   public static ConfigurationTransition computeTransition(
       Rule rule, @Nullable TransitionFactory<RuleTransitionData> trimmingTransitionFactory) {