toHaveBeenCalledBefore: Argument of type ... is not assignable to parameter of type 'Mock<any, any>'.

[Maxim-Mazurok]

Bug

• package version: 2.0.0
• node version: 17.2.0
• npm (or yarn) version: 8.1.4
• jest version: 27.5.1
• typescript version: 4.5.4

Relevant code or config

test.spec.ts:

import MyClass from "./MyClass";
import myFunction from "./myFunction";
jest.mock("./MyClass");

it("works", () => {
  // Arrange
  const param = 123;

  // Act
  myFunction(param); // uses MyClass

  // Assert

  expect(MyClass.prototype.initialize).toHaveBeenCalledBefore(
    MyClass.prototype.finalize
  );
});

jest.config.js

/** @type {import('@ts-jest/dist/types').InitialOptionsTsJest} */
module.exports = {
  preset: "ts-jest",
  testEnvironment: "node",
  resetMocks: true,
  setupFilesAfterEnv: ["jest-extended/all"],
  moduleNameMapper: {
    "^csv-stringify/sync":
      "<rootDir>/node_modules/csv-stringify/dist/cjs/sync.cjs",
  },
  globals: {
    "ts-jest": {
      isolatedModules: true,
      tsConfig: "tsconfig.json",
    },
  },
  clearMocks: true,
};

tsconfig.json:

{
  "compilerOptions": {
    "target": "ES2015",
    "moduleResolution": "Node",
    "strict": true,
    "esModuleInterop": true,
    "types": ["jest", "node"],
    "lib": ["ESNext"]
  }
}

What you did:

Run ./node_modules/.bin/tsc --noEmit -p . to see compilation errors, or check IDE.

What happened (please provide anything you think will help):

//redacted
bla.spec.ts:66:7 - error TS2345: Argument of type '(bla:bla) => Promise<void>' is not assignable to parameter of type 'Mock<any, any>'.
  Type '(bla:bla) => Promise<void>' is missing the following properties from type 'Mock<any, any>': getMockName, mock, mockClear, mockReset, and 12 more.

66       Bla.prototype.bla
         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[SimenB]

Could you put together a small reproduction?

[Maxim-Mazurok]

Could you put together a small reproduction?

Sure! Here you go: https://github.com/Maxim-Mazurok/jest-extended-456-reproduction

[SimenB]

Right, we should probably not force it to take a mock, and just something callable instead. It needs to be called with a mock tho, so maybe it's correct and you should use mocked?

diff --git i/test.spec.ts w/test.spec.ts
index 33048b5..dd8d6f0 100644
--- i/test.spec.ts
+++ w/test.spec.ts
@@ -9,6 +9,6 @@ it("works", () => {
 
   // Assert
   expect(MyClass.prototype.initialize).toHaveBeenCalledBefore(
-    MyClass.prototype.finalize
+    jest.mocked(MyClass.prototype.finalize)
   );
 });

[Maxim-Mazurok]

That worked! I remember seeing some SO answer that we used to have to use ts-jest and some similar helper, but then after jest got types - there was no more need for that helper. I'm not 100% sure that I recall that correctly tho, so maybe jest.mocked is the best answer indeed, I'll leave that to your judgment, thanks for helping out!