Reserve certain action mnemonics so they can't be used from Skylark.

If a reserved mnemonic is used, it is mangled.

RELNOTES:
PiperOrigin-RevId: 161970885

2 files changed, 30 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java b/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java
index ca8d5f93e0..ba82963582 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java
@@ -232,6 +232,11 @@ public final class BuildConfiguration implements BuildEvent {
     public PatchTransition topLevelConfigurationHook(Target toTarget) {
       return null;
     }
+
+    /** Returns a reserved set of action mnemonics. These cannot be used from a Skylark action. */
+    public ImmutableSet<String> getReservedActionMnemonics() {
+      return ImmutableSet.of();
+    }
   }
 
   private static final Label convertLabel(String input) throws OptionsParsingException {
@@ -1185,6 +1190,7 @@ public final class BuildConfiguration implements BuildEvent {
   private final ImmutableMap<String, Class<? extends Fragment>> skylarkVisibleFragments;
   private final RepositoryName mainRepositoryName;
   private final DynamicTransitionMapper dynamicTransitionMapper;
+  private final ImmutableSet<String> reservedActionMnemonics;
 
   /**
    * Directories in the output tree.
@@ -1579,6 +1585,12 @@ public final class BuildConfiguration implements BuildEvent {
 
     checksum = Fingerprint.md5Digest(buildOptions.computeCacheKey());
     hashCode = computeHashCode();
+
+    ImmutableSet.Builder<String> reservedActionMnemonics = ImmutableSet.builder();
+    for (Fragment fragment : fragments.values()) {
+      reservedActionMnemonics.addAll(fragment.getReservedActionMnemonics());
+    }
+    this.reservedActionMnemonics = reservedActionMnemonics.build();
   }
 
   /**
@@ -2765,6 +2777,10 @@ public final class BuildConfiguration implements BuildEvent {
     return skylarkVisibleFragments.keySet();
   }
 
+  public ImmutableSet<String> getReservedActionMnemonics() {
+    return reservedActionMnemonics;
+  }
+
   /**
    * Returns an extra transition that should apply to top-level targets in this
    * configuration. Returns null if no transition is needed.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/SkylarkActionFactory.java b/src/main/java/com/google/devtools/build/lib/rules/SkylarkActionFactory.java
index cb78d39a50..7d43824237 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/SkylarkActionFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/SkylarkActionFactory.java
@@ -590,8 +590,7 @@ public class SkylarkActionFactory implements SkylarkValue {
       }
     }
 
-    String mnemonic =
-        mnemonicUnchecked == Runtime.NONE ? "Generating" : (String) mnemonicUnchecked;
+    String mnemonic = getMnemonic(mnemonicUnchecked);
     builder.setMnemonic(mnemonic);
     if (envUnchecked != Runtime.NONE) {
       builder.setEnvironment(
@@ -624,6 +623,19 @@ public class SkylarkActionFactory implements SkylarkValue {
     ruleContext.registerAction(builder.build(ruleContext));
   }
 
+  private String getMnemonic(Object mnemonicUnchecked) {
+    String mnemonic =
+        mnemonicUnchecked == Runtime.NONE ? "SkylarkAction" : (String) mnemonicUnchecked;
+    if (ruleContext.getConfiguration().getReservedActionMnemonics().contains(mnemonic)) {
+      mnemonic = mangleMnemonic(mnemonic);
+    }
+    return mnemonic;
+  }
+
+  private static String mangleMnemonic(String mnemonic) {
+    return mnemonic + "FromSkylark";
+  }
+
   @SkylarkCallable(
       name = "expand_template",
       doc = "Creates a template expansion action.",