Access the equals util by grabbing it from the expect this arg. T…

…emporary hack until core jest exposes this util officially.

src/when.js

@@ -1,10 +1,26 @@
 const assert = require('assert')
-const utils = require('expect/build/jasmineUtils')
 
 let registry = new Set()
 
 const getCallLine = () => (new Error()).stack.split('\n')[4]
 
+/**
+ * A hack to capture a reference to the `equals` jasmineUtil
+ */
+let equals = () => {}
+expect.extend({
+  __capture_equals__ () {
+    equals = this.equals
+    return { pass: true }
+  }
+})
+expect().__capture_equals__()
+let JEST_MATCHERS_OBJECT = Symbol.for('$$jest-matchers-object')
+delete global[JEST_MATCHERS_OBJECT].matchers.__capture_equals__
+/**
+ * End hack
+ */
+
 const checkArgumentMatchers = (expectCall, args) => (match, matcher, i) => {
   // Propagate failure to the end
   if (!match) {
@@ -27,10 +43,10 @@ const checkArgumentMatchers = (expectCall, args) => (match, matcher, i) => {
   }
 
   if (isFunctionMatcher) {
-    return matcher(arg, utils.equals)
+    return matcher(arg, equals)
   }
 
-  return utils.equals(arg, matcher)
+  return equals(arg, matcher)
 }
 
 const NO_CALLED_WITH_YET = Symbol('NO_CALLED_WITH')
@@ -53,7 +69,7 @@ class WhenMock {
       // * call mocks with equal matchers are removed
       // * `once` mocks are used prioritized
       this.callMocks = this.callMocks
-        .filter((callMock) => once || callMock.once || !utils.equals(callMock.matchers, matchers))
+        .filter((callMock) => once || callMock.once || !equals(callMock.matchers, matchers))
         .concat({ matchers, mockImplementation, expectCall, once, called: false, id: this.nextCallMockId, callLine: getCallLine() })
         .sort((a, b) => {
           // Once mocks should appear before the rest

src/when.test.js

@@ -2,11 +2,9 @@ const errMsg = ({ expect, actual }) =>
   new RegExp(`Expected.*${expect}.*\\nReceived.*${actual}`)
 
 describe('When', () => {
-  let spyEquals, when, WhenMock, resetAllWhenMocks, verifyAllWhenMocksCalled
+  let when, WhenMock, resetAllWhenMocks, verifyAllWhenMocksCalled
 
   beforeEach(() => {
-    spyEquals = jest.spyOn(require('expect/build/jasmineUtils'), 'equals')
-
     when = require('./when').when
     resetAllWhenMocks = require('./when').resetAllWhenMocks
     verifyAllWhenMocksCalled = require('./when').verifyAllWhenMocksCalled
@@ -129,37 +127,6 @@ describe('When', () => {
   })
 
   describe('mock implementation', () => {
-    it('offloads equality check to jasmine equals helper', () => {
-      const fn = jest.fn()
-
-      when(fn).calledWith(1).mockReturnValue('x')
-
-      expect(fn(1)).toEqual('x')
-      expect(spyEquals).toBeCalledWith(1, 1)
-
-      expect(fn(2)).toEqual(undefined)
-      expect(spyEquals).toBeCalledWith(2, 1)
-    })
-
-    it('works with multiple args', () => {
-      const fn = jest.fn()
-
-      const anyString = expect.any(String)
-      const myFunction = function () {}
-
-      when(fn)
-        .calledWith(1, 'foo', true, anyString, undefined, myFunction)
-        .mockReturnValue('x')
-
-      expect(fn(1, 'foo', true, 'whatever', undefined, myFunction)).toEqual('x')
-      expect(spyEquals).toBeCalledWith(1, 1)
-      expect(spyEquals).toBeCalledWith('foo', 'foo')
-      expect(spyEquals).toBeCalledWith(true, true)
-      expect(spyEquals).toBeCalledWith('whatever', anyString)
-      expect(spyEquals).toBeCalledWith(undefined, undefined)
-      expect(spyEquals).toBeCalledWith(myFunction, myFunction)
-    })
-
     it('only matches exact sets of args, too little or too many args do not trigger mock return', () => {
       const fn = jest.fn()