2022-12-22
2600
#node
Godwin Ekuma
9184
Dec 22, 2022 ⋅ 9 min read

Node.js unit testing using Mocha, Chai, and Sinon

Godwin Ekuma I learn so that I can solve problems.

Recent posts:

Wasm 3 Before GTA 6 LogRocket Article

We got Wasm 3.0 before GTA 6: Meet the web’s new engine

Discover how WebAssembly 3.0’s garbage collector, exception handling, and Memory64 transform Wasm into a true mainstream web platform.

Ikeh Akinyemi
Oct 3, 2025 ⋅ 2 min read

How to use AI to build accurate ShadCN components

AI agents often break shadcn/ui components with outdated docs or made-up props. The MCP server fixes this by giving live access to registries. In this tutorial, we’ll set it up and build a Kanban board to show it in action.

Chizaram Ken
Oct 3, 2025 ⋅ 5 min read
Rust Project for Web Services LogRocket Article

The best way to structure Rust web services

Learn how to structure Rust web services with clean architecture, Cargo workspaces, and modular crates for scalable, maintainable backends.

Jude Miracle
Oct 2, 2025 ⋅ 2 min read
andrew evans headshot

A spec-first workflow for building with agentic AI

Andrew Evans gives his take on agentic AI and walks through a step-by-step method to build a spec-first workflow using Claude Code.

Andrew Evans
Oct 1, 2025 ⋅ 18 min read
View all posts

10 Replies to "Node.js unit testing using Mocha, Chai, and Sinon"

  1. Should the user repository take UserModel as an argument in the constructor? I’m wondering how the test suite for UserRepository knows anything about the stubbed model if the stubbed model is not passed in to the constructor.

  2. The Model exists in the global scope of the user repository, this allows the repository class have access to it. So in the test if the UserModel is referenced the stub will passed instead of the actual model.

  3. Hi thanks for sharing!. I have a question if i wanna return response with 500 status code if repository can not save user to database i.e database connection is broken or like that.

  4. I getting this error, please help me to solve this!!!

    …\node_modules\yargs\yargs.js:1172
    else throw err
    ^

    Error: Cannot find module ‘../database’
    Require stack:
    – E:\Intenships\vivasvant systems llp\Web development\src\js\mocks\user.repository.test.js
    – E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\mocha.js
    – E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\cli\one-and-dones.js
    – E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\cli\options.js
    – E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\bin\mocha
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:610:15)
    at Function.Module._load (internal/modules/cjs/loader.js:526:27)
    at Module.require (internal/modules/cjs/loader.js:666:19)
    at require (internal/modules/cjs/helpers.js:16:16)
    at Object. (E:\Intenships\vivasvant systems llp\Web development\src\js\mocks\user.repository.test.js:5:23)
    at Module._compile (internal/modules/cjs/loader.js:759:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:770:10)
    at Module.load (internal/modules/cjs/loader.js:628:32)
    at Function.Module._load (internal/modules/cjs/loader.js:555:12)
    at Module.require (internal/modules/cjs/loader.js:666:19)
    at require (internal/modules/cjs/helpers.js:16:16)
    at E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\mocha.js:334:36
    at Array.forEach ()
    at Mocha.loadFiles (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\mocha.js:331:14)
    at Mocha.run (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\mocha.js:809:10)
    at Object.exports.singleRun (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\cli\run-helpers.js:108:16)
    at exports.runMocha (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\cli\run-helpers.js:142:13)
    at Object.exports.handler (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\cli\run.js:292:3)
    at Object.runCommand (E:\Intenships\vivasvant systems llp\Web development\node_modules\yargs\lib\command.js:242:26)
    at Object.parseArgs [as _parseArgs] (E:\Intenships\vivasvant systems llp\Web development\node_modules\yargs\yargs.js:1096:28)
    at Object.parse (E:\Intenships\vivasvant systems llp\Web development\node_modules\yargs\yargs.js:575:25)
    at Object.exports.main (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\lib\cli\cli.js:68:6)
    at Object. (E:\Intenships\vivasvant systems llp\Web development\node_modules\mocha\bin\mocha:162:29)
    at Module._compile (internal/modules/cjs/loader.js:759:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:770:10)
    at Module.load (internal/modules/cjs/loader.js:628:32)
    at Function.Module._load (internal/modules/cjs/loader.js:555:12)
    at Function.Module.runMain (internal/modules/cjs/loader.js:826:10)
    at internal/main/run_main_module.js:17:11
    npm ERR! Test failed. See above for more details.

  5. Hi there,
    thanks a lot for the excellent post.

    Just an update: faker is no longer available and has become a community project: npm install @faker-js/faker

  6. any mocking methods that don’t use chai ? Chai doesn’t support ES modules. Unit testing is a royal pain in the butt for node.js when needed a mocked database (WAY too complicated for something that should be simple). Just use a real database and be done with it (a staging database)

Leave a Reply