Restore Skylark "support" for inheritance
Classes of the same EvalUtils.getSkylarkType are once again the same for the
type inferencer.
Also, for debugging purposes, only print SkylarkClassObject as struct, not all classes that implement ClassObject yet are considered disjoint by the type engine.
--
MOS_MIGRATED_REVID=87933890
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java b/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
index f5dd753..15eaaa2 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
@@ -137,8 +137,14 @@
// TODO(bazel-team): move the following few type-related functions to SkylarkType
/**
- * Returns the Skylark equivalent type of the parameter. Note that the Skylark
- * language doesn't have inheritance.
+ * Compute the super-class of a class that Skylark considers as the Skylark type of its instances
+ *
+ * <p>Skylark type validation isn't otherwise equipped to deal with inheritance, so we must tell
+ * it which is the super-class or interface that matters for Skylark type compatibility.
+ * e.g. instances of all subclasses of SkylarkList are considered as being of type SkylarkList.
+ *
+ * @param c a class
+ * @return a super-class of c to be used in validation-time type inference.
*/
public static Class<?> getSkylarkType(Class<?> c) {
if (ImmutableList.class.isAssignableFrom(c)) {
@@ -155,6 +161,8 @@
} else if (Set.class.isAssignableFrom(c)) {
return Set.class;
} else {
+ // TODO(bazel-team): also unify all ClassObject, that we print the same?
+ //
// Check if one of the superclasses or implemented interfaces has the SkylarkModule
// annotation. If yes return that class.
Class<?> parent = getParentWithSkylarkModule(c);
@@ -222,7 +230,7 @@
return "FilesetEntry";
} else if (NestedSet.class.isAssignableFrom(c) || SkylarkNestedSet.class.isAssignableFrom(c)) {
return "set";
- } else if (ClassObject.class.isAssignableFrom(c)) {
+ } else if (ClassObject.SkylarkClassObject.class.isAssignableFrom(c)) {
return "struct";
} else if (SkylarkList.class.isAssignableFrom(c)) {
// TODO(bazel-team): Refactor the class hierarchy so we can distinguish list and tuple types.
