Application Name with accent character causes exception.

[LondonAtlas]

• Xcode version: 10.1 (10B61)
• Firebase SDK version: 5.18.0
• Firebase Component: Core
• Component version: 5.3.1

[REQUIRED] Step 3: Describe the problem

When trying to configure the object FirebaseApp using the initialiser configure(name: String. options: FirebaseOptions)supplying an application name that contains an accent such asē` will cause an exception.

Steps to reproduce:

Running the following line will cause the exception App name should only contain Letters, Numbers, Underscores, and Dashes. to be thrown.
FirebaseApp.configure(name: "hēllo", options: options)

Looking at the source code there is an if check looking for characters above and below a-z A-Z and 0-9.

FIRApp.m: 161
if (!((character >= 'a' && character <= 'z') || (character >= 'A' && character <= 'Z') || (character >= '0' && character <= '9') || character == '_' || character == '-')) { [NSException raise:kFirebaseCoreErrorDomain format:@"App name should only contain Letters, " @"Numbers, Underscores, and Dashes."]; }

Relevant Code:

let plistPath = Bundle.main.path(forResource: "MyGoogleServicePlist", ofType: "plist")
let googleService = try! PropertyListDecoder().decode(GoogleService.self, from: data)
let options = FirebaseOptions(googleAppID: googleService.appId, gcmSenderID: googleService.gcmId)
`FirebaseApp.configure(name: "hēllo", options: options)`

Due to a multi target workspace we are required to have custom names for the GoogleService-Info.plist which is why it contains a custom name in the sample above.

[paulb777]

Thanks for the report. This code has an overly constrained test to make sure that the characters are valid in a filename.

In the short-term, I sent a PR (#2614) to improve the error message. In the longer term, we'd be happy to consider a PR with a more expansive test.