Skylark: Allow builtin functions to be shadowed.

This change makes them consistent with global variables.
e.g.
  def foo(len): return len + 1  # now allowed

Redefinition is still forbidden.

--
MOS_MIGRATED_REVID=89383535

1 files changed, 3 insertions, 6 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/syntax/ValidationTests.java b/src/test/java/com/google/devtools/build/lib/syntax/ValidationTests.java
index 45ff6f6b28..22b4325c59 100644
--- a/src/test/java/com/google/devtools/build/lib/syntax/ValidationTests.java
+++ b/src/test/java/com/google/devtools/build/lib/syntax/ValidationTests.java
@@ -624,22 +624,19 @@ public class ValidationTests extends AbstractParserTestCase {
 
   @Test
   public void testModulesReadOnlyInFuncDefBody() {
-    checkError("Variable cmd_helper is read only",
-        "def func():",
+    parse("def func():",
         "  cmd_helper = set()");
   }
 
   @Test
   public void testBuiltinGlobalFunctionsReadOnlyInFuncDefBody() {
-    checkError("Variable rule is read only",
-        "def func():",
+    parse("def func():",
         "  rule = 'abc'");
   }
 
   @Test
   public void testBuiltinGlobalFunctionsReadOnlyAsFuncDefArg() {
-    checkError("Variable rule is read only",
-        "def func(rule):",
+    parse("def func(rule):",
         "  return rule");
   }