fix: Reset isolateModules after failing

CHANGELOG.md

@@ -11,6 +11,7 @@
 - `[jest-matcher-utils]` Fix diff highlight of symbol-keyed object. ([#9499](https://github.com/facebook/jest/pull/9499))
 - `[jest-resolve]` Fix module identity preservation with symlinks and browser field resolution ([#9511](https://github.com/facebook/jest/pull/9511))
 - `[jest-resolve]` Do not confuse directories with files ([#8912](https://github.com/facebook/jest/pull/8912))
+- `[jest-runtime]` Reset `isolateModules` if it fails ([#9541](https://github.com/facebook/jest/pull/9541))
 - `[jest-snapshot]` Downgrade semver to v6 to support node 8 ([#9451](https://github.com/facebook/jest/pull/9451))
 - `[jest-snapshot]` Properly indent new snapshots in the presences of existing ones ([#9523](https://github.com/facebook/jest/pull/9523))
 - `[jest-transform]` Correct sourcemap behavior for transformed and instrumented code ([#9460](https://github.com/facebook/jest/pull/9460))

packages/jest-runtime/src/__tests__/runtime_require_module_or_mock.test.js

@@ -240,6 +240,21 @@ describe('isolateModules', () => {
       expect(exports.getState()).toBe(1);
     }));
 
+  it('resets module after failing', () =>
+    createRuntime(__filename, {
+      moduleNameMapper,
+    }).then(runtime => {
+      expect(() =>
+        runtime.isolateModules(() => {
+          throw new Error('Error from isolated module');
+        }),
+      ).toThrowError('Error from isolated module');
+
+      runtime.isolateModules(() => {
+        expect(true).toBe(true);
+      });
+    }));
+
   it('cannot nest isolateModules blocks', () =>
     createRuntime(__filename, {
       moduleNameMapper,

packages/jest-runtime/src/index.ts

@@ -539,9 +539,12 @@ class Runtime {
     }
     this._isolatedModuleRegistry = new Map();
     this._isolatedMockRegistry = new Map();
-    fn();
-    this._isolatedModuleRegistry = null;
-    this._isolatedMockRegistry = null;
+    try {
+      fn();
+    } finally {
+      this._isolatedModuleRegistry = null;
+      this._isolatedMockRegistry = null;
+    }
   }
 
   resetModules() {