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TypeError: _fakeTimers(…).JestFakeTimers is not a constructor

See original GitHub issue

🐛 Bug Report

To Reproduce

Steps to reproduce the behavior:

Write test cases in Node js project
Set test: 'jest' script in package.json
Set a docker container with the following Dockerfile

# Dockerfile
FROM node:12.14.1-alpine

RUN mkdir /usr/app

WORKDIR /usr/app

COPY . /usr/app
RUN apk update && apk upgrade && apk add --no-cache git
RUN npm install -g jest
RUN npm i
RUN npm test
CMD npm start

The node_modules is always re-created from scratch while creating the Docker image.

Expected behavior

The RUN npm test should successfully run the test cases

Link to repl or repo (highly encouraged)

envinfo

System:
    OS: Linux 4.19 Alpine Linux
    CPU: (2) x64 Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz
  Binaries:
    Node: 12.14.1 - /usr/local/bin/node
    Yarn: 1.21.1 - /usr/local/bin/yarn
    npm: 6.13.4 - /usr/local/bin/npm
  npmPackages:
    jest: ^26.2.2 => 26.4.2

Crosspost on Stackoverflow: https://stackoverflow.com/q/63522963/2404470

Issue Analytics

State:
Created 3 years ago
Reactions:6
Comments:11

Top GitHub Comments

5reactions

Cedricvbcommented, Dec 1, 2020

What worked for me, was adding this to package.json:

"resolutions": { "jest-environment-jsdom": "^26.0.1" }

2reactions

oguzhnatlycommented, Feb 13, 2021

Adding this to package.json, worked for me too. Thanks, @Cedricvb!

"resolutions": { 
  "jest-environment-jsdom": "^26.0.1"
},

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