2022-12-22
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#node
Godwin Ekuma
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Dec 22, 2022 â‹… 9 min read

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

Godwin Ekuma I learn so that I can solve problems.

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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)

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