I am new to react-native and have found an error that makes absolutely no sense to me.

I am trying to include a calendar library:

I have included the dependency for that library in my package.json file and run npm install

The project was running fine and as expected. I have simply added one line of code to the project:

import { Calendar, CalendarList, Agenda } from 'react-native-calendars';

Nothing else. However now I am getting a red error message when the app loads on device and this is what my console is saying:

error: bundling failed: Error: While trying to resolve module xdate from file /Users/Alex/Documents/workspace/mobile/node_modules/react-native-calendars/src/index.js, the package /Users/Alex/Documents/workspace/mobile/node_modules/xdate/package.json was successfully found. However, this package itself specifies a main module field that could not be resolved (/Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js. Indeed, none of these files exist:

* /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json)

* /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js/index(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json) at ResolutionRequest.resolveDependency (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/node-haste/DependencyGraph/ResolutionRequest.js:103:15) at DependencyGraph.resolveDependency (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/node-haste/DependencyGraph.js:272:4579) at dependencies.map.relativePath (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:376:19) at Array.map () at resolveDependencies (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:374:16) at /Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:212:33 at Generator.next () at step (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:297:313) at /Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:297:473 at

However I have checked in the directory and in fact /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js does exist. However I do not see any of this part: (.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json)`

As to how /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js/index can exist, that doesn't make sense because xdate.js is not a directory.

Any help?

I am new to react-native and have found an error that makes absolutely no sense to me.

I am trying to include a calendar library: https://github.com/wix/react-native-calendars

I have included the dependency for that library in my package.json file and run npm install

The project was running fine and as expected. I have simply added one line of code to the project:

import { Calendar, CalendarList, Agenda } from 'react-native-calendars';

Nothing else. However now I am getting a red error message when the app loads on device and this is what my console is saying:

error: bundling failed: Error: While trying to resolve module xdate from file /Users/Alex/Documents/workspace/mobile/node_modules/react-native-calendars/src/index.js, the package /Users/Alex/Documents/workspace/mobile/node_modules/xdate/package.json was successfully found. However, this package itself specifies a main module field that could not be resolved (/Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js. Indeed, none of these files exist:

* /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json)

* /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js/index(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json) at ResolutionRequest.resolveDependency (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/node-haste/DependencyGraph/ResolutionRequest.js:103:15) at DependencyGraph.resolveDependency (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/node-haste/DependencyGraph.js:272:4579) at dependencies.map.relativePath (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:376:19) at Array.map () at resolveDependencies (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:374:16) at /Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:212:33 at Generator.next () at step (/Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:297:313) at /Users/Alex/Documents/workspace/mobile/node_modules/metro/src/DeltaBundler/traverseDependencies.js:297:473 at

However I have checked in the directory and in fact /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js does exist. However I do not see any of this part: (.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json)`

As to how /Users/Alex/Documents/workspace/mobile/node_modules/xdate/src/xdate.js/index can exist, that doesn't make sense because xdate.js is not a directory.

Any help?

• javascript
• ios
• reactjs
• react-native
• npm

• 1 stop the packager and run it again with react-native start – Hadnazzar Commented Mar 29, 2019 at 11:37

7 Answers 7

It Usually happens if you try to install a module while your packager is open.

Try to delete node_modules folder and close the packager. Then reinstall everything by npm install in your project directory.

First close your JavaScript bundler (Metro bundler in my case) and restart the application. This will create fresh dependency graph. This should solve the issue.

Just restart the bundler - no need to delete the Node Modules folder

I came across this issue when adding and using react-native-elements when using VS Code and Android Studio emulator on Linux Mint

In VS Code I had a terminal running Expo with Metro Bundler via 'npm start' command. After installing the react-native-elements in the folder (using 'npm install --save react-native-elements') and adding the import into the .js file I got the "However, this package itself specifies a main module field that could not be resolved" error.

In my case, this just involved a ^C in the terminal session to stop the Metro bundler and then running 'npm start' again. There was no need to delete the node modules folder at all.

If you're still getting the error even after deleting the ./node_modules folder and running npm install again, try doing the install with the --update-binary flag, i.e npm install --update-binary. This should clear out and rebuild any previously built packages on your machine.

Please don't delete the node modules folder. The bundler has least to deal with node modules folder.

Instead close all the terminals. If using VS-code close that also.

Close all the local host server ports and if possible restart the system. This might solve the issue.

If anyone have same issue, and remove node_module not working. Then you can try remove all node_module, package lock and using yarn to install node_module instead npm. Hope this help

None of the solutions above helped me except for restarting my MacBook. Wasted 30 minutes trying to fix this issue as I couldn't believe restarting my computer could be a solution.