StackRouter Reset Action should match state key (#3400)

packages/react-navigation/package.json

@@ -7,7 +7,8 @@
     "url": "git@github.com:react-navigation/react-navigation.git",
     "type": "git"
   },
-  "author": "Adam Miskiewicz <adam@sk3vy.com>, Eric Vicenti <ericvicenti@gmail.com>",
+  "author":
+    "Adam Miskiewicz <adam@sk3vy.com>, Eric Vicenti <ericvicenti@gmail.com>",
   "license": "BSD-2-Clause",
   "scripts": {
     "start": "npm run ios",
@@ -21,10 +22,7 @@
     "format": "eslint --fix .",
     "precommit": "lint-staged"
   },
-  "files": [
-    "lib",
-    "src"
-  ],
+  "files": ["lib", "src"],
   "peerDependencies": {
     "react": "*",
     "react-native": "*"
@@ -70,25 +68,15 @@
     "notify": true,
     "preset": "react-native",
     "testRegex": "./src/.*\\-test\\.js$",
-    "setupFiles": [
-      "<rootDir>/jest-setup.js"
-    ],
+    "setupFiles": ["<rootDir>/jest-setup.js"],
     "coverageDirectory": "./coverage/",
     "collectCoverage": true,
-    "collectCoverageFrom": [
-      "src/**/*.js"
-    ],
-    "coveragePathIgnorePatterns": [
-      "jest-setup.js"
-    ],
-    "modulePathIgnorePatterns": [
-      "examples"
-    ]
+    "coverageReporters": ["lcov"],
+    "collectCoverageFrom": ["src/**/*.js"],
+    "coveragePathIgnorePatterns": ["jest-setup.js"],
+    "modulePathIgnorePatterns": ["examples"]
   },
   "lint-staged": {
-    "*.js": [
-      "eslint --fix",
-      "git add"
-    ]
+    "*.js": ["eslint --fix", "git add"]
   }
 }

packages/react-navigation/src/routers/StackRouter.js

@@ -295,6 +295,12 @@ export default (routeConfigs, stackConfig = {}) => {
       }
 
       if (action.type === NavigationActions.RESET) {
+        // Only handle reset actions that are unspecified or match this state key
+        if (action.key != null && action.key != state.key) {
+          // Deliberately use != instead of !== so we can match null with
+          // undefined on either the state or the action
+          return state;
+        }
         const resetAction = action;
 
         return {

packages/react-navigation/src/routers/__tests__/StackRouter-test.js

@@ -768,6 +768,49 @@ describe('StackRouter', () => {
     expect(state2 && state2.routes[1].routeName).toEqual('Bar');
   });
 
+  test('Handles the reset action only with correct key set', () => {
+    const router = StackRouter({
+      Foo: {
+        screen: () => <div />,
+      },
+      Bar: {
+        screen: () => <div />,
+      },
+    });
+    const state1 = router.getStateForAction({ type: NavigationActions.INIT });
+    const resetAction = {
+      type: NavigationActions.RESET,
+      key: 'Bad Key',
+      actions: [
+        {
+          type: NavigationActions.NAVIGATE,
+          routeName: 'Foo',
+          params: { bar: '42' },
+          immediate: true,
+        },
+        {
+          type: NavigationActions.NAVIGATE,
+          routeName: 'Bar',
+          immediate: true,
+        },
+      ],
+      index: 1,
+    };
+    const state2 = router.getStateForAction(resetAction, state1);
+    expect(state2).toEqual(state1);
+    const state3 = router.getStateForAction(
+      {
+        ...resetAction,
+        key: state2.key,
+      },
+      state2
+    );
+    expect(state3 && state3.index).toEqual(1);
+    expect(state3 && state3.routes[0].params).toEqual({ bar: '42' });
+    expect(state3 && state3.routes[0].routeName).toEqual('Foo');
+    expect(state3 && state3.routes[1].routeName).toEqual('Bar');
+  });
+
   test('Handles the reset action with nested Router', () => {
     const ChildRouter = TabRouter({
       baz: {