chore(types): separate MatcherContext, MatcherUtils and MatcherState (#13141)

Author: SimenB

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ### Features
 
+- `[expect]` [**BREAKING**] Differentiate between `MatcherContext` `MatcherUtils` and `MatcherState` types ([#13141](https://github.com/facebook/jest/pull/13141))
 - `[jest-config]` [**BREAKING**] Make `snapshotFormat` default to `escapeString: false` and `printBasicPrototype: false` ([#13036](https://github.com/facebook/jest/pull/13036))
 - `[jest-environment-jsdom]` [**BREAKING**] Upgrade to `jsdom@20` ([#13037](https://github.com/facebook/jest/pull/13037), [#13058](https://github.com/facebook/jest/pull/13058))
 - `[@jest/globals]` Add `jest.Mocked`, `jest.MockedClass`, `jest.MockedFunction` and `jest.MockedObject` utility types ([#12727](https://github.com/facebook/jest/pull/12727))

packages/expect/__typetests__/expect.test.ts

@@ -8,9 +8,9 @@
 import {expectAssignable, expectError, expectType} from 'tsd-lite';
 import type {EqualsFunction, Tester} from '@jest/expect-utils';
 import {
+  MatcherContext,
   MatcherFunction,
-  MatcherFunctionWithState,
-  MatcherState,
+  MatcherFunctionWithContext,
   Matchers,
   expect,
 } from 'expect';
@@ -35,16 +35,16 @@ expectType<void>(
     toBeWithinRange(actual: number, floor: number, ceiling: number) {
       expectType<number>(this.assertionCalls);
       expectType<string | undefined>(this.currentTestName);
-      expectType<(() => void) | undefined>(this.dontThrow);
+      expectType<() => void>(this.dontThrow);
       expectType<Error | undefined>(this.error);
       expectType<EqualsFunction>(this.equals);
       expectType<boolean | undefined>(this.expand);
-      expectType<number | null | undefined>(this.expectedAssertionsNumber);
+      expectType<number | null>(this.expectedAssertionsNumber);
       expectType<Error | undefined>(this.expectedAssertionsNumberError);
-      expectType<boolean | undefined>(this.isExpectingAssertions);
+      expectType<boolean>(this.isExpectingAssertions);
       expectType<Error | undefined>(this.isExpectingAssertionsError);
-      expectType<boolean>(this.isNot);
-      expectType<string>(this.promise);
+      expectType<boolean | undefined>(this.isNot);
+      expectType<string | undefined>(this.promise);
       expectType<Array<Error>>(this.suppressedErrors);
       expectType<string | undefined>(this.testPath);
       expectType<MatcherUtils>(this.utils);
@@ -114,7 +114,7 @@ expectError(() => {
 });
 
 type ToBeWithinRange = (
-  this: MatcherState,
+  this: MatcherContext,
   actual: unknown,
   floor: number,
   ceiling: number,
@@ -133,7 +133,7 @@ const toBeWithinRange: MatcherFunction<[floor: number, ceiling: number]> = (
 
 expectAssignable<ToBeWithinRange>(toBeWithinRange);
 
-type AllowOmittingExpected = (this: MatcherState, actual: unknown) => any;
+type AllowOmittingExpected = (this: MatcherContext, actual: unknown) => any;
 
 const allowOmittingExpected: MatcherFunction = (
   actual: unknown,
@@ -151,13 +151,13 @@ const allowOmittingExpected: MatcherFunction = (
 
 expectAssignable<AllowOmittingExpected>(allowOmittingExpected);
 
-// MatcherState
+// MatcherContext
 
 const toHaveContext: MatcherFunction = function (
   actual: unknown,
   ...expect: Array<unknown>
 ) {
-  expectType<MatcherState>(this);
+  expectType<MatcherContext>(this);
 
   if (expect.length !== 0) {
     throw new Error('This matcher does not take any expected argument.');
@@ -169,15 +169,15 @@ const toHaveContext: MatcherFunction = function (
   };
 };
 
-interface CustomState extends MatcherState {
+interface CustomContext extends MatcherContext {
   customMethod(): void;
 }
 
-const customContext: MatcherFunctionWithState<CustomState> = function (
+const customContext: MatcherFunctionWithContext<CustomContext> = function (
   actual: unknown,
   ...expect: Array<unknown>
 ) {
-  expectType<CustomState>(this);
+  expectType<CustomContext>(this);
   expectType<void>(this.customMethod());
 
   if (expect.length !== 0) {
@@ -191,16 +191,16 @@ const customContext: MatcherFunctionWithState<CustomState> = function (
 };
 
 type CustomStateAndExpected = (
-  this: CustomState,
+  this: CustomContext,
   actual: unknown,
   count: number,
 ) => any;
 
-const customStateAndExpected: MatcherFunctionWithState<
-  CustomState,
+const customStateAndExpected: MatcherFunctionWithContext<
+  CustomContext,
   [count: number]
 > = function (actual: unknown, count: unknown) {
-  expectType<CustomState>(this);
+  expectType<CustomContext>(this);
   expectType<void>(this.customMethod());
 
   return {

packages/expect/src/asymmetricMatchers.ts

@@ -17,6 +17,7 @@ import {pluralize} from 'jest-util';
 import {getState} from './jestMatchersObject';
 import type {
   AsymmetricMatcher as AsymmetricMatcherInterface,
+  MatcherContext,
   MatcherState,
 } from './types';
 
@@ -70,9 +71,11 @@ export abstract class AsymmetricMatcher<T>
 
   constructor(protected sample: T, protected inverse = false) {}
 
-  protected getMatcherContext(): MatcherState {
+  protected getMatcherContext(): MatcherContext {
     return {
-      ...getState(),
+      // eslint-disable-next-line @typescript-eslint/no-empty-function
+      dontThrow: () => {},
+      ...getState<MatcherState>(),
       equals,
       isNot: this.inverse,
       utils,

packages/expect/src/index.ts

@@ -41,7 +41,9 @@ import type {
   AsyncExpectationResult,
   Expect,
   ExpectationResult,
+  MatcherContext,
   MatcherState,
+  MatcherUtils,
   MatchersObject,
   PromiseMatcherFn,
   RawMatcherFn,
@@ -54,9 +56,11 @@ export type {
   AsymmetricMatchers,
   BaseExpect,
   Expect,
+  MatcherContext,
   MatcherFunction,
-  MatcherFunctionWithState,
+  MatcherFunctionWithContext,
   MatcherState,
+  MatcherUtils,
   Matchers,
 } from './types';
 
@@ -74,7 +78,7 @@ const createToThrowErrorMatchingSnapshotMatcher = function (
   matcher: RawMatcherFn,
 ) {
   return function (
-    this: MatcherState,
+    this: MatcherContext,
     received: any,
     testNameOrInlineSnapshot?: string,
   ) {
@@ -269,21 +273,29 @@ const makeThrowingMatcher = (
 ): ThrowingMatcherFn =>
   function throwingMatcher(...args): any {
     let throws = true;
-    const utils = {...matcherUtils, iterableEquality, subsetEquality};
+    const utils: MatcherUtils['utils'] = {
+      ...matcherUtils,
+      iterableEquality,
+      subsetEquality,
+    };
 
-    const matcherContext: MatcherState = {
+    const matcherUtilsThing: MatcherUtils = {
       // When throws is disabled, the matcher will not throw errors during test
       // execution but instead add them to the global matcher state. If a
       // matcher throws, test execution is normally stopped immediately. The
       // snapshot matcher uses it because we want to log all snapshot
       // failures in a test.
       dontThrow: () => (throws = false),
-      ...getState(),
       equals,
+      utils,
+    };
+
+    const matcherContext: MatcherContext = {
+      ...getState<MatcherState>(),
+      ...matcherUtilsThing,
       error: err,
       isNot,
       promise,
-      utils,
     };
 
     const processResult = (

packages/expect/src/jestMatchersObject.ts

@@ -24,7 +24,7 @@ const JEST_MATCHERS_OBJECT = Symbol.for('$$jest-matchers-object');
 export const INTERNAL_MATCHER_FLAG = Symbol.for('$$jest-internal-matcher');
 
 if (!Object.prototype.hasOwnProperty.call(globalThis, JEST_MATCHERS_OBJECT)) {
-  const defaultState: Partial<MatcherState> = {
+  const defaultState: MatcherState = {
     assertionCalls: 0,
     expectedAssertionsNumber: null,
     isExpectingAssertions: false,

packages/expect/src/print.ts

@@ -63,7 +63,7 @@ export const printCloseTo = (
   receivedDiff: number,
   expectedDiff: number,
   precision: number,
-  isNot: boolean,
+  isNot: boolean | undefined,
 ): string => {
   const receivedDiffString = stringify(receivedDiff);
   const expectedDiffString = receivedDiffString.includes('e')

packages/expect/src/types.ts

@@ -19,17 +19,21 @@ export type AsyncExpectationResult = Promise<SyncExpectationResult>;
 
 export type ExpectationResult = SyncExpectationResult | AsyncExpectationResult;
 
-export type MatcherFunctionWithState<
-  State extends MatcherState = MatcherState,
+export type MatcherFunctionWithContext<
+  Context extends MatcherContext = MatcherContext,
   Expected extends Array<any> = [] /** TODO should be: extends Array<unknown> = [] */,
-> = (this: State, actual: unknown, ...expected: Expected) => ExpectationResult;
+> = (
+  this: Context,
+  actual: unknown,
+  ...expected: Expected
+) => ExpectationResult;
 
 export type MatcherFunction<Expected extends Array<unknown> = []> =
-  MatcherFunctionWithState<MatcherState, Expected>;
+  MatcherFunctionWithContext<MatcherContext, Expected>;
 
 // TODO should be replaced with `MatcherFunctionWithContext`
-export type RawMatcherFn<State extends MatcherState = MatcherState> = {
-  (this: State, actual: any, ...expected: Array<any>): ExpectationResult;
+export type RawMatcherFn<Context extends MatcherContext = MatcherContext> = {
+  (this: Context, actual: any, ...expected: Array<any>): ExpectationResult;
   /** @internal */
   [INTERNAL_MATCHER_FLAG]?: boolean;
 };
@@ -41,27 +45,32 @@ export type MatchersObject = {
 export type ThrowingMatcherFn = (actual: any) => void;
 export type PromiseMatcherFn = (actual: any) => Promise<void>;
 
+export interface MatcherUtils {
+  dontThrow(): void;
+  equals: EqualsFunction;
+  utils: typeof jestMatcherUtils & {
+    iterableEquality: Tester;
+    subsetEquality: Tester;
+  };
+}
+
 export interface MatcherState {
   assertionCalls: number;
   currentTestName?: string;
-  dontThrow?(): void;
   error?: Error;
-  equals: EqualsFunction;
   expand?: boolean;
-  expectedAssertionsNumber?: number | null;
+  expectedAssertionsNumber: number | null;
   expectedAssertionsNumberError?: Error;
-  isExpectingAssertions?: boolean;
+  isExpectingAssertions: boolean;
   isExpectingAssertionsError?: Error;
-  isNot: boolean;
-  promise: string;
+  isNot?: boolean;
+  promise?: string;
   suppressedErrors: Array<Error>;
   testPath?: string;
-  utils: typeof jestMatcherUtils & {
-    iterableEquality: Tester;
-    subsetEquality: Tester;
-  };
 }
 
+export type MatcherContext = MatcherUtils & Readonly<MatcherState>;
+
 export type AsymmetricMatcher = {
   asymmetricMatch(other: unknown): boolean;
   toString(): string;

packages/jest-expect/src/index.ts

@@ -18,9 +18,11 @@ import type {JestExpect} from './types';
 export type {
   AsymmetricMatchers,
   Matchers,
+  MatcherContext,
   MatcherFunction,
-  MatcherFunctionWithState,
+  MatcherFunctionWithContext,
   MatcherState,
+  MatcherUtils,
 } from 'expect';
 export type {JestExpect} from './types';
 

packages/jest-snapshot/src/index.ts

@@ -7,7 +7,7 @@
 
 import * as fs from 'graceful-fs';
 import type {Config} from '@jest/types';
-import type {MatcherFunctionWithState} from 'expect';
+import type {MatcherFunctionWithContext} from 'expect';
 import type {FS as HasteFS} from 'jest-haste-map';
 import {
   BOLD_WEIGHT,
@@ -153,7 +153,7 @@ export const cleanup = (
   };
 };
 
-export const toMatchSnapshot: MatcherFunctionWithState<Context> = function (
+export const toMatchSnapshot: MatcherFunctionWithContext<Context> = function (
   received: unknown,
   propertiesOrHint?: object | string,
   hint?: string,
@@ -211,7 +211,7 @@ export const toMatchSnapshot: MatcherFunctionWithState<Context> = function (
   });
 };
 
-export const toMatchInlineSnapshot: MatcherFunctionWithState<Context> =
+export const toMatchInlineSnapshot: MatcherFunctionWithContext<Context> =
   function (
     received: unknown,
     propertiesOrSnapshot?: object | string,
@@ -408,7 +408,7 @@ const _toMatchSnapshot = (config: MatchSnapshotConfig) => {
   };
 };
 
-export const toThrowErrorMatchingSnapshot: MatcherFunctionWithState<Context> =
+export const toThrowErrorMatchingSnapshot: MatcherFunctionWithContext<Context> =
   function (received: unknown, hint?: string, fromPromise?: boolean) {
     const matcherName = 'toThrowErrorMatchingSnapshot';
 
@@ -427,7 +427,7 @@ export const toThrowErrorMatchingSnapshot: MatcherFunctionWithState<Context> =
     );
   };
 
-export const toThrowErrorMatchingInlineSnapshot: MatcherFunctionWithState<Context> =
+export const toThrowErrorMatchingInlineSnapshot: MatcherFunctionWithContext<Context> =
   function (received: unknown, inlineSnapshot?: string, fromPromise?: boolean) {
     const matcherName = 'toThrowErrorMatchingInlineSnapshot';
 

packages/jest-snapshot/src/types.ts

@@ -5,10 +5,10 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import type {MatcherState} from 'expect';
+import type {MatcherContext} from 'expect';
 import type SnapshotState from './State';
 
-export interface Context extends MatcherState {
+export interface Context extends MatcherContext {
   snapshotState: SnapshotState;
 }
 

packages/jest-types/__typetests__/expect.test.ts

@@ -361,16 +361,16 @@ expectType<void>(
     toBeWithinRange(actual: number, floor: number, ceiling: number) {
       expectType<number>(this.assertionCalls);
       expectType<string | undefined>(this.currentTestName);
-      expectType<(() => void) | undefined>(this.dontThrow);
+      expectType<() => void>(this.dontThrow);
       expectType<Error | undefined>(this.error);
       expectType<EqualsFunction>(this.equals);
       expectType<boolean | undefined>(this.expand);
-      expectType<number | null | undefined>(this.expectedAssertionsNumber);
+      expectType<number | null>(this.expectedAssertionsNumber);
       expectType<Error | undefined>(this.expectedAssertionsNumberError);
-      expectType<boolean | undefined>(this.isExpectingAssertions);
+      expectType<boolean>(this.isExpectingAssertions);
       expectType<Error | undefined>(this.isExpectingAssertionsError);
-      expectType<boolean>(this.isNot);
-      expectType<string>(this.promise);
+      expectType<boolean | undefined>(this.isNot);
+      expectType<string | undefined>(this.promise);
       expectType<Array<Error>>(this.suppressedErrors);
       expectType<string | undefined>(this.testPath);
       expectType<MatcherUtils>(this.utils);