Warning for brand new project instance: There are multiple modules with names that only differ in casing

[YukiDayDreamer]

I have tried to use the lasted vue-cli to create a completely new webpack template project. But it turns out to be some warnings:

 (webpack)/buildin/global.js
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* path\to\node_modules\webpack\buildin\global.js
    Used by 2 module(s), i. e.
    path\to\node_modules\punycode\punycode.js
* path\to\node_modules\webpack\buildin\global.js
    Used by 2 module(s), i. e.
    path\to\node_modules\vue\dist\vue.esm.js
 @ (webpack)/buildin/global.js
 @ path/to/node_modules/punycode/punycode.js
 @ path/to/node_modules/url/url.js
 @ (webpack)-dev-server/client?http://localhost:8080
 @ multi (webpack)-dev-server/client?http://localhost:8080 webpack/hot/dev-server ./src/main.js
msgWarnings @ client?cd17:147
onmessage @ socket.js?e5d0:38
EventTarget.dispatchEvent @ sockjs.js?69b1:170
(anonymous) @ sockjs.js?69b1:883
SockJS._transportMessage @ sockjs.js?69b1:881
EventEmitter.emit @ sockjs.js?69b1:86
WebSocketTransport.ws.onmessage @ sockjs.js?69b1:2957
client?cd17:147 (webpack)/hot/emitter.js
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* path\to\node_modules\webpack\hot\emitter.js
    Used by 1 module(s), i. e.
    path\to\node_modules\webpack-dev-server\client\index.js?http://localhost:8080
* path\to\node_modules\webpack\hot\emitter.js
    Used by 1 module(s), i. e.
    path\to\node_modules\webpack\hot\dev-server.js
 @ (webpack)/hot/emitter.js
 @ (webpack)-dev-server/client?http://localhost:8080
 @ multi (webpack)-dev-server/client?http://localhost:8080 webpack/hot/dev-server ./src/main.js
msgWarnings @ client?cd17:147
onmessage @ socket.js?e5d0:38
EventTarget.dispatchEvent @ sockjs.js?69b1:170
(anonymous) @ sockjs.js?69b1:883
SockJS._transportMessage @ sockjs.js?69b1:881
EventEmitter.emit @ sockjs.js?69b1:86
WebSocketTransport.ws.onmessage @ sockjs.js?69b1:2957
client?cd17:147 (webpack)/hot/log.js
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* path\to\node_modules\webpack\hot\log.js
    Used by 1 module(s), i. e.
    path\to\node_modules\webpack\hot nonrecursive /^\.\/log$/
* path\to\node_modules\webpack\hot\log.js
    Used by 2 module(s), i. e.
    path\to\node_modules\webpack\hot\dev-server.js
 @ (webpack)/hot/log.js
 @ (webpack)/hot nonrecursive ^\.\/log$
 @ (webpack)-dev-server/client?http://localhost:8080
 @ multi (webpack)-dev-server/client?http://localhost:8080 webpack/hot/dev-server ./src/main.js

[LinusBorg]

Can't reproduce this, sorry. What system and setup do you have (OS, node versions etc)

[dbjorge]

I can repro the issue in Windows 10 1709, Node 8.9.3, vue-cli 2.9.2, but the behavior only repros when running vue-cli from a prompt where the OS's name for the working directory differs from the name as cd'd to in the prompt environment (eg, in the below repro, I'm in a folder named C:\Code but my prompt is using working directory C:\code)

The issue repros without having to do a re-init (eg, in my repro below, you can workaround the issue with cd C:\Code\vue-cli-648-repro\, having previously run the vue init command from the context of C:\code\vue-cli-648-repro). Because of this, I think this is very unlikely to be a vue-cli issue (as opposed to a webpack/webpack-dev-server/etc issue), but I haven't root caused it/figured out the fix. Regardless, I wanted to leave the note here in case other new folks run into the same thing.

PS C:\code> (dir .. -filter code).FullName
C:\Code
PS C:\code> Get-ComputerInfo | fl WindowsBuildLabEx,WindowsCurrentVersion,WindowsEditionId,WindowsInstallationType,Windo
wsProductName,WindowsVersion


WindowsBuildLabEx       : 16299.15.amd64fre.rs3_release.170928-1534
WindowsCurrentVersion   : 6.3
WindowsEditionId        : Professional
WindowsInstallationType : Client
WindowsProductName      : Windows 10 Pro
WindowsVersion          : 1709



PS C:\code> node --version
v8.9.3
PS C:\code> npm --version
5.5.1
PS C:\code> npm -g list vue-cli
C:\Users\dbjor\AppData\Roaming\npm
`-- vue-cli@2.9.2

PS C:\code> vue init webpack vue-cli-648-repro

? Project name vue-cli-648-repro
? Project description A Vue.js project
? Author Dan Bjorge <dan@dbjorge.net>
? Vue build standalone
? Install vue-router? Yes
? Use ESLint to lint your code? Yes
? Pick an ESLint preset Standard
? Set up unit tests Yes
? Pick a test runner jest
? Setup e2e tests with Nightwatch? Yes

   vue-cli · Generated "vue-cli-648-repro".

   To get started:

     cd vue-cli-648-repro
     npm install
     npm run dev

   Documentation can be found at https://vuejs-templates.github.io/webpack

PS C:\code> cd .\vue-cli-648-repro\
PS C:\code\vue-cli-648-repro> npm install
npm WARN deprecated content-type-parser@1.0.2: This package has been renamed whatwg-mimetype; please upgrade.

> chromedriver@2.33.2 install C:\code\vue-cli-648-repro\node_modules\chromedriver
> node install.js

Downloading https://chromedriver.storage.googleapis.com/2.33/chromedriver_win32.zip
Saving to C:\Users\dbjor\AppData\Local\Temp\chromedriver\chromedriver_win32.zip
Received 781K...
Received 1568K...
Received 2352K...
Received 3136K...
Received 3920K...
Received 4125K total.
Extracting zip contents
Copying to target path C:\code\vue-cli-648-repro\node_modules\chromedriver\lib\chromedriver
Done. ChromeDriver binary available at C:\code\vue-cli-648-repro\node_modules\chromedriver\lib\chromedriver\chromedriver.exe

> uglifyjs-webpack-plugin@0.4.6 postinstall C:\code\vue-cli-648-repro\node_modules\webpack\node_modules\uglifyjs-webpack-plugin
> node lib/post_install.js

npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.1.3 (node_modules\fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.1.3: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})

added 1458 packages in 36.287s
PS C:\code\vue-cli-648-repro> npm run dev

> vue-cli-648-repro@1.0.0 dev C:\code\vue-cli-648-repro
> webpack-dev-server --inline --progress --config build/webpack.dev.conf.js

 95% emitting

 WARNING  Compiled with 3 warnings                                                                              20:12:16

 warning  in C:/Code/vue-cli-648-repro/node_modules/webpack/buildin/global.js

There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* C:\Code\vue-cli-648-repro\node_modules\webpack\buildin\global.js
    Used by 2 module(s), i. e.
    C:\Code\vue-cli-648-repro\node_modules\punycode\punycode.js
* C:\code\vue-cli-648-repro\node_modules\webpack\buildin\global.js
    Used by 1 module(s), i. e.
    C:\code\vue-cli-648-repro\node_modules\vue\dist\vue.esm.js

 warning  in C:/Code/vue-cli-648-repro/node_modules/webpack/hot/emitter.js

There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* C:\Code\vue-cli-648-repro\node_modules\webpack\hot\emitter.js
    Used by 1 module(s), i. e.
    C:\Code\vue-cli-648-repro\node_modules\webpack-dev-server\client\index.js?http://localhost:8080
* C:\code\vue-cli-648-repro\node_modules\webpack\hot\emitter.js
    Used by 1 module(s), i. e.
    C:\code\vue-cli-648-repro\node_modules\webpack\hot\dev-server.js

 warning  in C:/Code/vue-cli-648-repro/node_modules/webpack/hot/log.js

There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* C:\Code\vue-cli-648-repro\node_modules\webpack\hot\log.js
    Used by 1 module(s), i. e.
    C:\Code\vue-cli-648-repro\node_modules\webpack\hot nonrecursive /^\.\/log$/
* C:\code\vue-cli-648-repro\node_modules\webpack\hot\log.js
    Used by 2 module(s), i. e.
    C:\code\vue-cli-648-repro\node_modules\webpack\hot\dev-server.js


PS C:\code\vue-cli-648-repro> # Not necessary to re-init to change to/from repro behavior

PS C:\code\vue-cli-648-repro> cd C:\Code\vue-cli-648-repro\
PS C:\Code\vue-cli-648-repro> npm run dev

> vue-cli-648-repro@1.0.0 dev C:\Code\vue-cli-648-repro
> webpack-dev-server --inline --progress --config build/webpack.dev.conf.js

 95% emitting

 DONE  Compiled successfully in 3298ms                                                                          20:47:56

 I  Your application is running here: http://localhost:8080