jest-haste-map: @providesModule naming collision: Duplicate module name

[C2P1]

Hello,

Trying to run npm start on my project is now giving me the following error:

Error: jest-haste-map: @providesModule naming collision:
Duplicate module name: app
Paths:
/Users/c2p1/apps/awsmobilejs/#current-backend-info/cloud-api/Table/package.json
collides with
/Users/c2p1/apps/awsmobilejs/backend/cloud-api/Table/package.json

both of these package.json are identical and have the field:
"name": "app"

I am now currently unable to build and run my app due to this.

Whenever I use the command awsmobile pull I enter Yes to the question

Sync corresponding contents in backend/ with #current-backend-info/

and it to me it appears like this is where the issue is created. Should I not be syncing the contents? How do I fix this so I can build my project?

Thanks!

[UnleashedMind]

The contents in the #current-backend-info folder and the backend folder are pretty much the same after each synchronization with the cloud.
Then you develop your work in the backend and push the changes up to the cloud.
That's the reason you see the two packages named the same.

Jest is a unit test framework, it's not part of the awsmobile-cli.
I'd suggest you to exclude the #current-backend-info folder from being tested by jest-haste-map, and you should be able to build your project fine.

[C2P1]

Thanks for your reply!

I know that this used to be fine, as I've had no problems before, but since upgrading to react-native 0.56.0 this issue has started happening. Right now, I currently can't find how to exclude the #current-backend-info from the jest-haste-map. I will keep looking into it, but it seems odd that to be able to use awsmobile I then have to manually exclude some of the files it installs.

On the topic of awsmobile, is there any reason my project needs awsmobile folders prepended by a '~'? Can these be deleted?

[UnleashedMind]

awsmobile folders with name prefix '~' are backups, awsmobile-cli does not want you to loose your files, so if the cli is creating the contents in the awsmobilejs folder anew, it backs up the original contents in the backup folders.
If you don't need those files, you can delete them, the cli doesn't use them.

[juang97]

Hi,
I am also running into the same problem but instead i have the package.json colliding with two different tables on my Cloud-api folder

This is my folder hierarchy

any ideas on how to fix this? Thank you

[C2P1]

Hi @juang97, did this issue start being a problem after you had run a npm install or npm audit fix ?

[C2P1]

@UnleashedMind, if I delete #current-backend-info will things still work? I have yet to find a way to exclude it from Jest-Haste-Map and this is preventing my app from running.

Next time when I do an

awsmobile pull

and say yes to sync info, will I then get a new #current-backend-info folder created? I

[juang97]

@C2P1. I was able to patch this issue by blacklisting the Table name under the awsmobile folder. This approach doesnt exactly fix the problem but everything is working as expected for me. If you are interested, take a look here https://stackoverflow.com/questions/41813211/how-to-make-react-native-packager-ignore-certain-directories

[michaelcuneo]

I'm having this exact same problem. I was just about to post and ask a question about it... but it's here already.

(node:90796) UnhandledPromiseRejectionWarning: Error: jest-haste-map: @providesModule naming collision:
Duplicate module name: app
Paths: /Users/mjc128/Desktop/ReactNativeKoalaCall/awsmobilejs/backend/cloud-api/globalSettings/package.json collides with /Users/mjc128/Desktop/ReactNativeKoalaCall/awsmobilejs/backend/cloud-api/imageSets/package.json

I've tried multiple solutions, but nothing... I can no longer compile my app. I've tried clearing the jest cache map on run, and nothing, tried removing react-native and reinstalling react-native and nothing, I also tried removing the entire node_modules folder and reinitialising, but nothing.

[michaelcuneo]

As stated by @juang97 I followed the same procedure, and added the following to a file nammed rn-cli.config.js in the root of my project...

const blacklist = require('metro').createBlacklist;

module.exports = {
  getBlacklistRE: function() {
    return blacklist([/awsmobilejs\/.*/]);
  }
};

Works 100% fine since then.

Thanks guys.

[7772]

@michaelcuneo 's solution worked for me. Thanks :)

[Ivanrs297]

Hi, im having this problem too, but with react-native module. The build is succeeded, but when it start to run the app the error show the following:

I tried to delete and reinstall node_modules, clear cache, but nothing.

[emlynmac]

Yup, I'm seeing the same thing @Ivanrs297. I'm trying to figure out how to block jest from peering into my iOS build area now...