diff --git a/tools/BUILD.bazel b/tools/BUILD.bazel
index 3332dda7cc3..1616d80f885 100644
--- a/tools/BUILD.bazel
+++ b/tools/BUILD.bazel
@@ -1,4 +1,4 @@
-load("@aspect_rules_js//js:defs.bzl", "js_library")
+load("@aspect_rules_js//js:defs.bzl", "js_library", "js_test")
 load("@aspect_rules_ts//ts:defs.bzl", "ts_config")
 load("@bazel_skylib//rules:native_binary.bzl", "native_binary")
 
@@ -18,6 +18,17 @@ js_library(
     ],
 )
 
+js_test(
+    name = "custom-eslint-rules-test",
+    size = "small",
+    data = [
+        "custom-eslint-rules.mjs",
+        "//:node_modules/eslint",
+    ],
+    entry_point = "custom-eslint-rules.test.mjs",
+    tags = ["js-test"],
+)
+
 ts_config(
     name = "base-tsconfig",
     src = "base.tsconfig.json",
diff --git a/tools/custom-eslint-rules.test.mjs b/tools/custom-eslint-rules.test.mjs
new file mode 100644
index 00000000000..1f50cae18f8
--- /dev/null
+++ b/tools/custom-eslint-rules.test.mjs
@@ -0,0 +1,127 @@
+/**
+ * Tests for custom ESLint rules.
+ */
+import { RuleTester } from 'eslint';
+import { describe, it } from 'node:test';
+import { noExportDefaultOfImportStar } from './custom-eslint-rules.mjs';
+
+// Create a new RuleTester instance
+const ruleTester = new RuleTester({
+  languageOptions: {
+    ecmaVersion: 2022,
+    sourceType: 'module',
+  },
+});
+
+describe('no-export-default-of-import-star', () => {
+  it('should validate the rule', () => {
+    ruleTester.run('no-export-default-of-import-star', noExportDefaultOfImportStar, {
+      valid: [
+        // Valid: Regular named import
+        {
+          code: `
+            import { foo } from 'some-module';
+            export default foo;
+          `,
+        },
+        // Valid: Inline default export
+        {
+          code: `
+            export default { foo: 'bar' };
+          `,
+        },
+        // Valid: Export namespace import as named export
+        {
+          code: `
+            import * as foo from 'some-module';
+            export { foo };
+          `,
+        },
+        // Valid: Namespace import used for something other than export default
+        {
+          code: `
+            import * as foo from 'some-module';
+            const bar = foo;
+          `,
+        },
+        // Valid: Export default with non-identifier
+        {
+          code: `
+            import * as foo from 'some-module';
+            export default foo.bar;
+          `,
+        },
+        // Valid: Re-export all
+        {
+          code: `
+            export * from 'some-module';
+          `,
+        },
+        // Valid: Named imports with object literal default export
+        {
+          code: `
+            import { var1, var2 } from 'some-module';
+            export * from 'some-module';
+            export default { var1, var2 };
+          `,
+        },
+      ],
+
+      invalid: [
+        // Invalid: Export namespace import as default
+        {
+          code: `
+            import * as foo from 'some-module';
+            export default foo;
+          `,
+          errors: [
+            {
+              messageId: 'noExportDefaultOfImportStar',
+              data: { source: 'some-module' },
+            },
+          ],
+        },
+        // Invalid: Common pattern with _default
+        {
+          code: `
+            import * as _default from 'some-module';
+            export default _default;
+          `,
+          errors: [
+            {
+              messageId: 'noExportDefaultOfImportStar',
+              data: { source: 'some-module' },
+            },
+          ],
+        },
+        // Invalid: Namespace import with scoped package
+        {
+          code: `
+            import * as myModule from '@scope/package';
+            export default myModule;
+          `,
+          errors: [
+            {
+              messageId: 'noExportDefaultOfImportStar',
+              data: { source: '@scope/package' },
+            },
+          ],
+        },
+        // Invalid: Multiple imports, only one violates rule
+        {
+          code: `
+            import { named } from 'module1';
+            import * as ns from 'module2';
+            export default ns;
+          `,
+          errors: [
+            {
+              messageId: 'noExportDefaultOfImportStar',
+              data: { source: 'module2' },
+            },
+          ],
+        },
+      ],
+    });
+  });
+});