From 6767717d0bf53ed93799a39728bf1677a3d26934 Mon Sep 17 00:00:00 2001
From: Maribeth Bottorff <maribethb@google.com>
Date: Mon, 1 Apr 2024 14:13:25 -0700
Subject: [PATCH] feat: allow duplicate registry values (#7988)

---
 core/registry.ts             | 9 +++++++--
 tests/mocha/registry_test.js | 9 +++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/core/registry.ts b/core/registry.ts
index 3645a6fdf..727711d48 100644
--- a/core/registry.ts
+++ b/core/registry.ts
@@ -162,8 +162,13 @@ export function register<T>(
   // Validate that the given class has all the required properties.
   validate(type, registryItem);
 
-  // Don't throw an error if opt_allowOverrides is true.
-  if (!opt_allowOverrides && typeRegistry[caselessName]) {
+  // Don't throw an error if opt_allowOverrides is true,
+  // or if we're trying to register the same item.
+  if (
+    !opt_allowOverrides &&
+    typeRegistry[caselessName] &&
+    typeRegistry[caselessName] !== registryItem
+  ) {
     throw Error(
       'Name "' +
         caselessName +
diff --git a/tests/mocha/registry_test.js b/tests/mocha/registry_test.js
index fd37c6e69..b562606f4 100644
--- a/tests/mocha/registry_test.js
+++ b/tests/mocha/registry_test.js
@@ -47,6 +47,15 @@ suite('Registry', function () {
     test('Overwrite a Key', function () {
       Blockly.registry.register('test', 'test_name', TestClass);
       chai.assert.throws(function () {
+        // Registers a different object under the same name
+        Blockly.registry.register('test', 'test_name', {});
+      }, 'already registered');
+    });
+
+    test('Register a Duplicate Item', function () {
+      Blockly.registry.register('test', 'test_name', TestClass);
+      chai.assert.doesNotThrow(function () {
+        // Registering the same object under the same name is allowed
         Blockly.registry.register('test', 'test_name', TestClass);
       }, 'already registered');
     });