From f0f7b2f408aff132a0ecfcf1beea75caae33d3a9 Mon Sep 17 00:00:00 2001
From: plf <plf@google.com>
Date: Tue, 27 Apr 2021 15:11:35 -0700
Subject: [PATCH] Allow transitions for builtin rules without allowlist

Only Blaze team members can write a built-in rule. Instead of having to modify
the allowlist every time we starlarkify a native transition, it's preferable to
always allow builtins to use Starlark transitions.

RELNOTES:none
PiperOrigin-RevId: 370772711
---
 .../lib/analysis/starlark/StarlarkRuleClassFunctions.java      | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkRuleClassFunctions.java b/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkRuleClassFunctions.java
index 1ec5e1cf9451ed..b294fc210290e6 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkRuleClassFunctions.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkRuleClassFunctions.java
@@ -792,7 +792,8 @@ public void export(EventHandler handler, Label starlarkLabel, String ruleClassNa
       }
       // TODO(b/121385274): remove when we stop allowlisting starlark transitions
       if (hasStarlarkDefinedTransition) {
-        if (!hasFunctionTransitionAllowlist) {
+        if (!starlarkLabel.getRepository().getName().equals("@_builtins")
+            && !hasFunctionTransitionAllowlist) {
           errorf(
               handler,
               "Use of Starlark transition without allowlist attribute"