Simplify implementation and decouple it from expect

Author: rogeliog

packages/expect/src/index.ts

@@ -43,7 +43,6 @@ import {
   INTERNAL_MATCHER_FLAG,
   getState,
   setState,
-  clearState,
   getMatchers,
   setMatchers,
 } from './jestMatchersObject';
@@ -403,7 +402,6 @@ expect.assertions = assertions;
 expect.hasAssertions = hasAssertions;
 expect.getState = getState;
 expect.setState = setState;
-expect.clearState = clearState;
 expect.extractExpectedAssertionsErrors = extractExpectedAssertionsErrors;
 
 const expectExport = expect as Expect;

packages/expect/src/jestMatchersObject.ts

@@ -37,10 +37,6 @@ export const setState = (state: object) => {
   Object.assign((global as any)[JEST_MATCHERS_OBJECT].state, state);
 };
 
-export const clearState = () => {
-  getState().snapshotState.clear();
-};
-
 export const getMatchers = () => (global as any)[JEST_MATCHERS_OBJECT].matchers;
 
 export const setMatchers = (

packages/expect/src/types.ts

@@ -6,7 +6,6 @@
  *
  */
 import {Config} from '@jest/types';
-import {SnapshotStateType} from 'jest-snapshot';
 import * as jestMatcherUtils from 'jest-matcher-utils';
 import {INTERNAL_MATCHER_FLAG} from './jestMatchersObject';
 
@@ -45,7 +44,6 @@ export type MatcherState = {
   isExpectingAssertions?: boolean;
   isNot: boolean;
   promise: string;
-  snapshotState: SnapshotStateType;
   suppressedErrors: Array<Error>;
   testPath?: Config.Path;
   utils: typeof jestMatcherUtils & {

packages/jest-circus/src/eventHandler.ts

@@ -148,11 +148,7 @@ const eventHandler: Circus.EventHandler = (event, state): void => {
       break;
     }
     case 'test_retry': {
-      // Clear errors so tests can be retried (and not immediately fail)
       event.test.errors = [];
-      // Clear any snapshot data that occurred in previous test run
-      global.expect.clearState();
-
       break;
     }
     case 'run_start': {

packages/jest-circus/src/legacy-code-todo-rewrite/jestAdapterInit.ts

@@ -12,6 +12,7 @@ import {extractExpectedAssertionsErrors, getState, setState} from 'expect';
 import {formatExecError, formatResultsErrors} from 'jest-message-util';
 import {
   SnapshotState,
+  SnapshotStateType,
   addSerializer,
   buildSnapshotResolver,
 } from 'jest-snapshot';
@@ -131,6 +132,8 @@ export const initialize = ({
   });
   setState({snapshotState, testPath});
 
+  addEventHandler(handleSnapshotStateAfterRetry(snapshotState));
+
   // Return it back to the outer scope (test runner outside the VM).
   return {globals, snapshotState};
 };
@@ -243,6 +246,17 @@ export const runAndTransformResultsToJestFormat = async ({
   };
 };
 
+const handleSnapshotStateAfterRetry = (snapshotState: SnapshotStateType) => (
+  event: Circus.Event,
+) => {
+  switch (event.name) {
+    case 'test_retry': {
+      // Clear any snapshot data that occurred in previous test run
+      snapshotState.clear();
+    }
+  }
+};
+
 const eventHandler = (event: Circus.Event) => {
   switch (event.name) {
     case 'test_start': {

packages/jest-snapshot/src/State.ts

@@ -42,12 +42,12 @@ export default class SnapshotState {
   private _index: number;
   private _updateSnapshot: Config.SnapshotUpdateState;
   private _snapshotData: SnapshotData;
+  private _initialData: SnapshotData;
   private _snapshotPath: Config.Path;
   private _inlineSnapshots: Array<InlineSnapshot>;
   private _uncheckedKeys: Set<string>;
   private _getBabelTraverse: () => Function;
   private _getPrettier: () => null | any;
-  private _reinitializeData: () => void;
 
   added: number;
   expand: boolean;
@@ -61,7 +61,7 @@ export default class SnapshotState {
       this._snapshotPath,
       options.updateSnapshot,
     );
-
+    this._initialData = data;
     this._snapshotData = data;
     this._dirty = dirty;
     this._getBabelTraverse = options.getBabelTraverse;
@@ -76,17 +76,6 @@ export default class SnapshotState {
     this.unmatched = 0;
     this._updateSnapshot = options.updateSnapshot;
     this.updated = 0;
-
-    this._reinitializeData = () => {
-      this._snapshotData = data;
-      this._inlineSnapshots = [];
-      this._counters = new Map();
-      this._index = 0;
-      this.added = 0;
-      this.matched = 0;
-      this.unmatched = 0;
-      this.updated = 0;
-    };
   }
 
   markSnapshotsAsCheckedForTest(testName: string) {
@@ -122,7 +111,14 @@ export default class SnapshotState {
   }
 
   clear() {
-    this._reinitializeData();
+    this._snapshotData = this._initialData;
+    this._inlineSnapshots = [];
+    this._counters = new Map();
+    this._index = 0;
+    this.added = 0;
+    this.matched = 0;
+    this.unmatched = 0;
+    this.updated = 0;
   }
 
   save() {