Skylark rules can no longer overwrite built-in attributes.
--
MOS_MIGRATED_REVID=103931317
diff --git a/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java b/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java
index 8429617..9e84f0b 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java
@@ -770,13 +770,16 @@
/**
* Adds or overrides the attribute in the rule class. Meant for Skylark usage.
+ *
+ * @throws IllegalArgumentException if the attribute overrides an existing attribute (will be
+ * legal in the future).
*/
public void addOrOverrideAttribute(Attribute attribute) {
- if (attributes.containsKey(attribute.getName())) {
- overrideAttribute(attribute);
- } else {
- addAttribute(attribute);
- }
+ String name = attribute.getName();
+ // Attributes may be overridden in the future.
+ Preconditions.checkArgument(!attributes.containsKey(name),
+ "There is already a built-in attribute '%s' which cannot be overridden", name);
+ addAttribute(attribute);
}
/** True if the rule class contains an attribute named {@code name}. */
