How to test an npm module with peerDependencies?

Question

I am new to understand peerDependencies, and I have read the following references seeking as to how to test an npm module contains peerDependencies within its package.json:

However, I have not found a clear solution for testing npm with peerDependencies. Some recommend adding the peerDependencies as globals, and some reference to include peerDependencies within devDependencies, and neither seems right.

For example, I have a package that has a peer dependency, a custom logger, and this logger needs to be configured by its host package before it can be used.

This is how I perform most tests scripted in using this Gulp task:

function testRunner() {
  return (
    gulp
      .src('./tests/**/*.js', { read: false })
      .pipe(
        mocha({
          exit: true,
          timeout: 10000
        })
      )
      .on('error', console.error)
  );
}

I did receive a helpful suggestion (see comments below, @estus) to use npm-install-peers, however, I am not yet certain if it can configure a peer dependency before usage, as it would be performed by the host package.

Feedback and Suggestions are most appreciated.

What exactly do you mean by 'testing'? Are you looking to write automated tests? Are you talking about manually testing something? Are you talking about something else? — Pedro A
– Pedro A, Commented Jan 18, 2019 at 1:14
@pedro-a Thank you for your response, I appreciate that I should add clarity as to what I mean by "testing". I have just edited my question with Gulp task that performs a mocha test. So, what I mean by testing is first localized followed by CI automated tests. — Jeff
– Jeff, Commented Jan 18, 2019 at 1:34
@estus Thank you for your suggestion, I am checking it out now and connecting with its author. I forgot one detail, the peer dependency also needs to be configured by the peer's parent. Adding that detail to my initial question. — Jeff
– Jeff, Commented Jan 18, 2019 at 16:15
I am currently checking out another npm package: npm install-peerdeps — Jeff
– Jeff, Commented Jan 18, 2019 at 17:27

deerawan · Accepted Answer · 2019-01-22 10:05:33Z

42

In my case, I developed a library last time that use ioredis as peer dependency. My solution was to put that library as well in dev dependency.

// package.json
"peerDependencies": {
    "ioredis": "4.x"
},
"devDependencies": {
    "ioredis": "4.x"
}

it worked well and no issue so far using this approach.

answered Jan 22, 2019 at 10:05

deerawan

8,5035 gold badges46 silver badges51 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Robert Over a year ago

Also, to test your package on different peer versions, you can temporarily change that dev dependency to specific versions, re-install dependencies (I use npm ci), and run your tests.

Jeff · Accepted Answer · 2019-01-21 19:17:38Z

8

I had connected with the authors of npm-install-peers, and the response from one of the authors,

When it comes to testing your package/project on CI, I believe the correct way to do things is manually adding your peer dependencies to your dev dependencies. No need for this little tool.

answered Jan 21, 2019 at 19:17

Jeff

1,8755 gold badges31 silver badges50 bronze badges

1 Comment

Catfish Over a year ago

I added the same devDependency as is in my peerDependencies so that my unit tests run. These seems like the most appropriate way to do this.

Collectives™ on Stack Overflow

How to test an npm module with peerDependencies?

2 Answers 2

1 Comment

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related