Update PKCE-related messaging (#789)

Auth0/WebAuthError.swift

@@ -49,7 +49,7 @@ public struct WebAuthError: Auth0Error {
 
     /// The Auth0 application does not support authentication with Proof Key for Code Exchange (PKCE).
     /// PKCE support needs to be enabled in the settings page of the [Auth0 application](https://manage.auth0.com/#/applications/),
-    /// by setting the **Application Type** to 'Native' and the **Token Endpoint Authentication Method** to 'None'.
+    /// by setting the **Application Type** to 'Native'.
     /// This error does not include a ``Auth0Error/cause-9wuyi``.
     public static let pkceNotAllowed: WebAuthError = .init(code: .pkceNotAllowed)
 
@@ -84,7 +84,7 @@ extension WebAuthError {
         case .userCancelled: return "The user cancelled the Web Auth operation."
         case .pkceNotAllowed: return "Unable to perform authentication with PKCE."
             + " Enable PKCE support in the settings page of the Auth0 application, by setting the"
-            + " 'Application Type' to 'Native' and the 'Token Endpoint Authentication Method' to 'None'."
+            + " 'Application Type' to 'Native'."
         case .noAuthorizationCode(let values): return "The callback URL is missing the authorization code in its"
             + " query parameters (\(values))."
         case .idTokenValidationFailed: return "The ID token validation performed after authentication failed."

Auth0Tests/WebAuthErrorSpec.swift

@@ -103,7 +103,7 @@ class WebAuthErrorSpec: QuickSpec {
             it("should return message for PKCE not allowed") {
                 let message = "Unable to perform authentication with PKCE."
                 + " Enable PKCE support in the settings page of the Auth0 application, by setting the"
-                + " 'Application Type' to 'Native' and the 'Token Endpoint Authentication Method' to 'None'."
+                + " 'Application Type' to 'Native'."
                 let error = WebAuthError(code: .pkceNotAllowed)
                 expect(error.localizedDescription) == message
             }

README.md

@@ -76,6 +76,9 @@ Head to the [Auth0 Dashboard](https://manage.auth0.com/#/applications/) and crea
 
 Auth0.swift needs the **Client ID** and **Domain** of the Auth0 application to communicate with Auth0. You can find these details in the settings page of your Auth0 application. If you have a [custom domain](https://auth0.com/docs/customize/custom-domains), use your custom domain instead of the value from the settings page.
 
+> **Warning**
+> Make sure that the Auth0 application type is **Native**. Otherwise, you might run into errors due to the different configuration of other application types.
+
 #### Configure Client ID and Domain with a plist
 
 Create a `plist` file named `Auth0.plist` in your app bundle with the following content:
@@ -153,9 +156,6 @@ For example, if your iOS bundle identifier was `com.example.MyApp` and your Auth
 com.example.MyApp://example.us.auth0.com/ios/com.example.MyApp/callback
 ```
 
-> **Note**
-> Make sure that the **Token Endpoint Authentication Method** [setting](https://auth0.com/docs/get-started/applications/confidential-and-public-applications/view-application-type) is set to `None`.
-
 #### Configure custom URL scheme
 
 Back in Xcode, go to the **Info** tab of your app target settings. In the **URL Types** section, click the **＋** button to add a new entry. There, enter `auth0` into the **Identifier** field and `$(PRODUCT_BUNDLE_IDENTIFIER)` into the **URL Schemes** field.