fix: construct mather context for asymmetric matchers on demand

jestjs · Oct 5, 2021 · f3e582d · f3e582d
1 parent f13abff
commit f3e582d
Show file tree

Hide file tree

Showing 2 changed files with 28 additions and 28 deletions.
diff --git a/packages/expect/src/asymmetricMatchers.ts b/packages/expect/src/asymmetricMatchers.ts
@@ -12,30 +12,28 @@ import {getState} from './jestMatchersObject';
 import type {MatcherState} from './types';
 import {iterableEquality, subsetEquality} from './utils';
 
-export class AsymmetricMatcher<T> {
-  protected sample: T;
-  protected readonly matcherState: MatcherState;
-  $$typeof: symbol;
-  // TODO: remove this field in Jest 28 (use `matcherState`)
-  inverse?: boolean;
+const utils = Object.freeze({
+  ...matcherUtils,
+  iterableEquality,
+  subsetEquality,
+});
 
-  constructor(sample: T, isNot = false) {
-    this.$$typeof = Symbol.for('jest.asymmetricMatcher');
-    this.sample = sample;
+export abstract class AsymmetricMatcher<T> {
+  $$typeof = Symbol.for('jest.asymmetricMatcher');
 
-    const utils = {...matcherUtils, iterableEquality, subsetEquality};
+  constructor(protected sample: T, protected inverse = false) {}
 
-    const matcherContext: MatcherState = {
+  protected getMatcherContext(): MatcherState {
+    return {
       ...getState(),
       equals,
-      isNot,
+      isNot: this.inverse,
       utils,
     };
-
-    this.inverse = matcherContext.isNot;
-
-    this.matcherState = matcherContext;
   }
+
+  abstract asymmetricMatch(other: unknown): boolean;
+  abstract toString(): string;
 }
 
 class Any extends AsymmetricMatcher<any> {
@@ -152,11 +150,11 @@ class ArrayContaining extends AsymmetricMatcher<Array<unknown>> {
           other.some(another => equals(item, another)),
         ));
 
-    return this.matcherState.isNot ? !result : result;
+    return this.inverse ? !result : result;
   }
 
   toString() {
-    return `Array${this.matcherState.isNot ? 'Not' : ''}Containing`;
+    return `Array${this.inverse ? 'Not' : ''}Containing`;
   }
 
   getExpectedType() {
@@ -190,11 +188,11 @@ class ObjectContaining extends AsymmetricMatcher<Record<string, unknown>> {
       }
     }
 
-    return this.matcherState.isNot ? !result : result;
+    return this.inverse ? !result : result;
   }
 
   toString() {
-    return `Object${this.matcherState.isNot ? 'Not' : ''}Containing`;
+    return `Object${this.inverse ? 'Not' : ''}Containing`;
   }
 
   getExpectedType() {
@@ -213,11 +211,11 @@ class StringContaining extends AsymmetricMatcher<string> {
   asymmetricMatch(other: string) {
     const result = isA('String', other) && other.includes(this.sample);
 
-    return this.matcherState.isNot ? !result : result;
+    return this.inverse ? !result : result;
   }
 
   toString() {
-    return `String${this.matcherState.isNot ? 'Not' : ''}Containing`;
+    return `String${this.inverse ? 'Not' : ''}Containing`;
   }
 
   getExpectedType() {
@@ -236,11 +234,11 @@ class StringMatching extends AsymmetricMatcher<RegExp> {
   asymmetricMatch(other: string) {
     const result = isA('String', other) && this.sample.test(other);
 
-    return this.matcherState.isNot ? !result : result;
+    return this.inverse ? !result : result;
   }
 
   toString() {
-    return `String${this.matcherState.isNot ? 'Not' : ''}Matching`;
+    return `String${this.inverse ? 'Not' : ''}Matching`;
   }
 
   getExpectedType() {

diff --git a/packages/expect/src/jestMatchersObject.ts b/packages/expect/src/jestMatchersObject.ts
@@ -68,16 +68,16 @@ export const setMatchers = (
 
         asymmetricMatch(other: unknown) {
           const {pass} = matcher.call(
-            this.matcherState,
+            this.getMatcherContext(),
             other,
             ...this.sample,
           ) as SyncExpectationResult;
 
-          return this.matcherState.isNot ? !pass : pass;
+          return this.inverse ? !pass : pass;
         }
 
         toString() {
-          return `${this.matcherState.isNot ? 'not.' : ''}${key}`;
+          return `${this.inverse ? 'not.' : ''}${key}`;
         }
 
         getExpectedType() {
@@ -92,7 +92,9 @@ export const setMatchers = (
       expect[key] = (...sample: [unknown, unknown]) =>
         new CustomMatcher(false, ...sample);
       if (!expect.not) {
-        expect.not = {};
+        throw new Error(
+          '`expect.not` is not defined - please report this bug to https://github.com/facebook/jest',
+        );
       }
       expect.not[key] = (...sample: [unknown, unknown]) =>
         new CustomMatcher(true, ...sample);