fix(getCustomBrowser): explicitly set browser to nil if type not found

[valentinrey]

Fixes #1063

Description

This pull request fixes an issue in the getCustomBrowser: method where an invalid or empty browser type (e.g., an empty string or NSNull) received from the JavaScript layer would not be properly handled. In iOS release builds, such values caused the method to pass a non-nil result, leading to an attempt to execute an invalid browser block and resulting in a crash.

• Updated getCustomBrowser: in RNAppAuth.m to explicitly check the return value of browser. If the value is not in the dictionary, it will return nil to trigger an ephemeral session.
• Updated gitignore.

Steps to verify

1. Configure the authorize method with a configuration object with no iosCustomBrowser, that includes:

const config = {
  issuer: "https://youridprovider.com",
  clientId: "yourClientID",
  redirectUrl: "yourapp://callback",
  scopes: ["openid"],
  iosPrefersEphemeralSession: true,
  usePKCE: true,
};

2. Call authorize(config) in your React Native code.
3. Build the app in iOS release mode (the issue is only reproducible in release builds for iOS).
4. Observe that the app not crashes.

[changeset-bot]

🦋 Changeset detected

Latest commit: 443871b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
react-native-app-auth	Patch

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Name	Status	Preview	Comments	Updated (UTC)
react-native-app-auth	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 12, 2025 1:26pm

[tuladharjaa]

@valentinrey logout does not work after these changes

[valentinrey]

@tuladharjaa, I had to refactor my logout logic a bit. Basically moved the check up in the file tree

[sepperousseau]

@valentinrey what do you mean with "moved the check up in the file tree"?
For me the login works now, but the logout doesn't work anymore.

[valentinrey]

@tuladharjaa I have an application with a simple auth logic, and take a check in App.tsx now that was in another file. It checks if the user is authenticated, if not, runs a logout function that also wipes tokens and other stored data

[seanfar]

@sepperousseau @tuladharjaa

I've introduced what I think may be the fix for logout in #1070. Please take a look at your convenience to see if this addresses the issue you're experiencing. ty!