[CB-13937] `cordova platform add ios` fails if `ios` folder is present

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 8.0.0
• Component/s: cordova-lib
• Assignee: Unassigned
• Reporter: Jan Piotrowski (janpio)
• Created: 01/Mar/18 20:11
• Updated: 13/Jun/18 01:04

Description

If there is a folder called like the platform you want to install, it will fail.

See here for an example where an `ios` folder was present before executing `cordova platform add ios`:

```
MacBook-Pro:project sujan$ cordova platform add ios
(node:3439) UnhandledPromiseRejectionWarning: CordovaError: Error: npm: Command failed with exit code 1 Error output:
npm ERR! code ENOLOCAL
npm ERR! Could not install from "ios" as it does not contain a package.json file.

npm ERR! A complete log of this run can be found in:
npm ERR!     /Users/sujan/.npm/_logs/2018-03-01T19_56_48_106Z-debug.log
    at /Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/cordova-fetch/index.js:104:29
    at _rejected (/Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:864:24)
    at /Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:890:30
    at Promise.when (/Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:1142:31)
    at Promise.promise.promiseDispatch (/Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:808:41)
    at /Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:624:44
    at runSingle (/Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:137:13)
    at flush (/Users/sujan/.nvm/versions/node/v9.4.0/lib/node_modules/cordova/node_modules/q/q.js:125:13)
    at process._tickCallback (internal/process/next_tick.js:150:11)
(node:3439) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:3439) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

When renaming the `ios` folder to `_ios` it all works as expected:

MacBook-Pro:project sujan$ cordova platform add ios
Using cordova-fetch for cordova-ios@~4.5.4
Adding ios project...
Creating Cordova project for the iOS platform:
	Path: platforms/ios
...

Is this expected behavior?
Is there a simple way to work around this without removing or renaming the folder?