feat(client)!: use unique endpoint typestates

UPGRADE.md

@@ -1,5 +1,20 @@
 # Upgrade Guide
 
+## Upgrading from 5.x to 6.x
+
+### Update typestate generic types on `Client`
+
+The 6.x release includes breaking changes that make `Client` typestates specific to the type of endpoint being set. 
+This makes it possible to tell at a glance which endpoints are set for each instance of `Client`.
+
+```rust
+// v5.x syntax:
+let client: BasicClient<EndpointSet, EndpointNotSet, EndpointNotSet, EndpointSet, EndpointSet> = todo!();
+
+// v6.x syntax
+let client: BasicClient<AuthEndpointSet, DeviceAuthEndpointNotSet, IntrospectionEndpointNotSet, RevocationEndpointSet, TokenEndpointSet> = todo!();
+```
+
 ## Upgrading from 4.x to 5.x
 
 The 5.0 release includes breaking changes to address several long-standing API issues, along with

examples/wunderlist.rs

@@ -18,13 +18,16 @@ use oauth2::basic::{
     BasicErrorResponse, BasicRevocationErrorResponse, BasicTokenIntrospectionResponse,
     BasicTokenType,
 };
-use oauth2::reqwest;
-use oauth2::StandardRevocableToken;
+use oauth2::{
+    reqwest, AuthEndpointNotSet, IntrospectionEndpointNotSet, RevocationEndpointNotSet,
+    TokenEndpointNotSet,
+};
 use oauth2::{
     AccessToken, AuthUrl, AuthorizationCode, Client, ClientId, ClientSecret, CsrfToken,
-    EmptyExtraTokenFields, EndpointNotSet, ExtraTokenFields, RedirectUrl, RefreshToken, Scope,
-    TokenResponse, TokenUrl,
+    EmptyExtraTokenFields, ExtraTokenFields, RedirectUrl, RefreshToken, Scope, TokenResponse,
+    TokenUrl,
 };
+use oauth2::{DeviceAuthEndpointNotSet, StandardRevocableToken};
 use serde::{Deserialize, Serialize};
 use url::Url;
 
@@ -35,11 +38,11 @@ use std::time::Duration;
 
 type SpecialTokenResponse = NonStandardTokenResponse<EmptyExtraTokenFields>;
 type SpecialClient<
-    HasAuthUrl = EndpointNotSet,
-    HasDeviceAuthUrl = EndpointNotSet,
-    HasIntrospectionUrl = EndpointNotSet,
-    HasRevocationUrl = EndpointNotSet,
-    HasTokenUrl = EndpointNotSet,
+    HasAuthUrl = AuthEndpointNotSet,
+    HasDeviceAuthUrl = DeviceAuthEndpointNotSet,
+    HasIntrospectionUrl = IntrospectionEndpointNotSet,
+    HasRevocationUrl = RevocationEndpointNotSet,
+    HasTokenUrl = TokenEndpointNotSet,
 > = Client<
     BasicErrorResponse,
     SpecialTokenResponse,

src/basic.rs

@@ -1,19 +1,23 @@
 use crate::{
+    client::{
+        AuthEndpointNotSet, DeviceAuthEndpointNotSet, IntrospectionEndpointNotSet,
+        RevocationEndpointNotSet, TokenEndpointNotSet,
+    },
     revocation::{RevocationErrorResponseType, StandardRevocableToken},
-    Client, EmptyExtraTokenFields, EndpointNotSet, ErrorResponseType, RequestTokenError,
-    StandardErrorResponse, StandardTokenIntrospectionResponse, StandardTokenResponse, TokenType,
+    Client, EmptyExtraTokenFields, ErrorResponseType, RequestTokenError, StandardErrorResponse,
+    StandardTokenIntrospectionResponse, StandardTokenResponse, TokenType,
 };
 
 use std::fmt::Error as FormatterError;
 use std::fmt::{Debug, Display, Formatter};
 
 /// Basic OAuth2 client specialization, suitable for most applications.
 pub type BasicClient<
-    HasAuthUrl = EndpointNotSet,
-    HasDeviceAuthUrl = EndpointNotSet,
-    HasIntrospectionUrl = EndpointNotSet,
-    HasRevocationUrl = EndpointNotSet,
-    HasTokenUrl = EndpointNotSet,
+    HasAuthUrl = AuthEndpointNotSet,
+    HasDeviceAuthUrl = DeviceAuthEndpointNotSet,
+    HasIntrospectionUrl = IntrospectionEndpointNotSet,
+    HasRevocationUrl = RevocationEndpointNotSet,
+    HasTokenUrl = TokenEndpointNotSet,
 > = Client<
     BasicErrorResponse,
     BasicTokenResponse,