feat!: replace union accessors with generic Is, As and TryGet and implicit conversions

Author: ariesclark

README.md

@@ -62,7 +62,7 @@ IVRChat vrchat = new VRChatClientBuilder() // More options available
 var currentUser = await vrchat.LoginAsync();
 Console.WriteLine($"Logged in as {currentUser.DisplayName}!");
 
-var user = (await vrchat.Users.GetUserAsync("usr_f2049d71-e76b-42d2-a8bd-43deec9c004e")).GetUser();
+User user = await vrchat.Users.GetUserAsync("usr_f2049d71-e76b-42d2-a8bd-43deec9c004e");
 Console.WriteLine($"Found user {user.DisplayName}, joined at {user.DateJoined}");
 
 var world = await vrchat.Worlds.GetWorldAsync("wrld_ba913a96-fac4-4048-a062-9aa5db092812");
@@ -162,7 +162,7 @@ IVRChat vrchat = new VRChatClientBuilder() // More options available
     .Build();
 
 var response = await vrchat.Authentication.GetCurrentUserAsync();
-var methods = (response.ActualInstance as RequiresTwoFactorAuth)?.VarRequiresTwoFactorAuth ?? new List<TwoFactorAuthType>();
+var methods = response.TryGet<RequiresTwoFactorAuth>(out var pending) ? pending.VarRequiresTwoFactorAuth : new List<TwoFactorAuthType>();
 
 if(methods.Contains(TwoFactorAuthType.EmailOtp))
 {
@@ -179,7 +179,7 @@ else if(methods.Contains(TwoFactorAuthType.Totp))
     var otpResponse = await vrchat.Authentication.Verify2FAAsync(new TwoFactorAuthCode(code));
 }
 
-var user = (await vrchat.Authentication.GetCurrentUserAsync()).GetCurrentUser();
+CurrentUser user = await vrchat.Authentication.GetCurrentUserAsync();
 
 Console.WriteLine($"Logged in as {user.DisplayName}!");
 ```
@@ -221,7 +221,7 @@ try
     // so we can see what the API expects from us
     ApiResponse<CurrentUserLoginResponse> currentUserResp = authApi.GetCurrentUserWithHttpInfo();
 
-    if(currentUserResp.Data.ActualInstance is RequiresTwoFactorAuth pending)
+    if(currentUserResp.Data.TryGet<RequiresTwoFactorAuth>(out var pending))
     {
         if (pending.VarRequiresTwoFactorAuth.Contains(TwoFactorAuthType.EmailOtp)) // If the API wants us to send an Email OTP code
         {
@@ -235,10 +235,10 @@ try
     }
 
     // We can now get our CurrentUser :D
-    CurrentUser currentUser = authApi.GetCurrentUser().GetCurrentUser();
+    CurrentUser currentUser = authApi.GetCurrentUser();
     Console.WriteLine("Logged in as {0}", currentUser.DisplayName);
 
-    User user = userApi.GetUser("usr_f2049d71-e76b-42d2-a8bd-43deec9c004e").GetUser();
+    User user = userApi.GetUser("usr_f2049d71-e76b-42d2-a8bd-43deec9c004e");
     Console.WriteLine("Found user {0}, joined {1}", user.DisplayName, user.DateJoined);
 
     World world = worldApi.GetWorld("wrld_ba913a96-fac4-4048-a062-9aa5db092812");

examples/VRChat.API.Examples.AspNetCore/Controllers/HomeController.cs

@@ -1,5 +1,6 @@
 using Microsoft.AspNetCore.Mvc;
 using VRChat.API.Client;
+using VRChat.API.Model;
 
 namespace VRChat.API.Examples.AspNetCore.Controllers;
 
@@ -23,7 +24,7 @@ public IActionResult Index()
     [Route("/api/users/current")]
     public async Task<IActionResult> GetCurrentUserAsync()
     {
-        var user = (await _vrchat.Authentication.GetCurrentUserAsync()).GetCurrentUser();
+        CurrentUser user = await _vrchat.Authentication.GetCurrentUserAsync();
 
         // Profile fields (bio, bio links, badges, ...) are no longer part of CurrentUser.
         // They live behind getPublicProfile; asSelf includes the owner-only view.
@@ -45,7 +46,7 @@ public async Task<IActionResult> GetCurrentUserAsync()
     [Route("/api/users/{id}")]
     public async Task<IActionResult> GetUserByIdAsync(string id)
     {
-        var user = (await _vrchat.Users.GetUserAsync(id)).GetUser();
+        User user = await _vrchat.Users.GetUserAsync(id);
 
         // User no longer carries the profile or current-avatar fields; fetch them from the
         // public profile instead.

examples/VRChat.API.Examples.Console/Program.cs

@@ -21,7 +21,7 @@ public static async Task Main(string[] args)
             var currentUser = await vrchat.LoginAsync();
             System.Console.WriteLine($"Logged in as {currentUser.DisplayName}!");
 
-            var user = (await vrchat.Users.GetUserAsync("usr_f2049d71-e76b-42d2-a8bd-43deec9c004e")).GetUser();
+            User user = await vrchat.Users.GetUserAsync("usr_f2049d71-e76b-42d2-a8bd-43deec9c004e");
             System.Console.WriteLine($"Found user {user.DisplayName}, joined at {user.DateJoined}");
 
             var world = await vrchat.Worlds.GetWorldAsync("wrld_ba913a96-fac4-4048-a062-9aa5db092812");

templates/modelAnyOf.mustache

@@ -73,15 +73,12 @@
         {{^vendorExtensions.x-duplicated-data-type}}
         {{^isNull}}
 
+        {{^isAnyType}}{{^isFreeFormObject}}
         /// <summary>
-        /// Get the actual instance of `{{dataType}}`. If the actual instance is not `{{dataType}}`,
-        /// the InvalidClassException will be thrown
+        /// Converts to the <c>{{dataType}}</c> this instance holds, throwing <see cref="InvalidCastException"/> when it holds another type.
         /// </summary>
-        /// <returns>An instance of {{dataType}}</returns>
-        public {{{dataType}}} Get{{#lambda.titlecase}}{{baseType}}{{/lambda.titlecase}}{{#isArray}}{{#lambda.titlecase}}{{{dataFormat}}}{{/lambda.titlecase}}{{/isArray}}()
-        {
-            return ({{{dataType}}})ActualInstance;
-        }
+        public static implicit operator {{{dataType}}}({{classname}} value) => ({{{dataType}}})value?.ActualInstance;
+        {{/isFreeFormObject}}{{/isAnyType}}
         {{/isNull}}
         {{/vendorExtensions.x-duplicated-data-type}}
         {{/composedSchemas.anyOf}}

templates/modelOneOf.mustache

@@ -73,15 +73,12 @@
         {{^vendorExtensions.x-duplicated-data-type}}
         {{^isNull}}
 
+        {{^isAnyType}}{{^isFreeFormObject}}
         /// <summary>
-        /// Get the actual instance of `{{dataType}}`. If the actual instance is not `{{dataType}}`,
-        /// the InvalidClassException will be thrown
+        /// Converts to the <c>{{dataType}}</c> this instance holds, throwing <see cref="InvalidCastException"/> when it holds another type.
         /// </summary>
-        /// <returns>An instance of {{dataType}}</returns>
-        public {{{dataType}}} Get{{#lambda.titlecase}}{{baseType}}{{/lambda.titlecase}}{{#isArray}}{{#lambda.titlecase}}{{{dataFormat}}}{{/lambda.titlecase}}{{/isArray}}()
-        {
-            return ({{{dataType}}})this.ActualInstance;
-        }
+        public static implicit operator {{{dataType}}}({{classname}} value) => ({{{dataType}}})value?.ActualInstance;
+        {{/isFreeFormObject}}{{/isAnyType}}
         {{/isNull}}
         {{/vendorExtensions.x-duplicated-data-type}}
         {{/composedSchemas.oneOf}}

wrapper/VRChat.API/Model/GeneratedModelExtensions.cs

@@ -11,4 +11,35 @@ public partial class TwoFactorAuthCode : ITwoFactorCode { }
     /// two-factor code is accepted.
     /// </summary>
     public partial class TwoFactorEmailCode : ITwoFactorCode { }
+
+    /// <summary>
+    /// Additions to the generated <see cref="AbstractOpenAPISchema"/>, which every union type extends.
+    /// </summary>
+    public abstract partial class AbstractOpenAPISchema
+    {
+        /// <summary>
+        /// Whether this instance holds a <typeparamref name="T"/>.
+        /// </summary>
+        public bool Is<T>() => ActualInstance is T;
+
+        /// <summary>
+        /// The <typeparamref name="T"/> this instance holds, throwing <see cref="System.InvalidCastException"/> when it holds another type.
+        /// </summary>
+        public T As<T>() => (T)ActualInstance;
+
+        /// <summary>
+        /// Gets the <typeparamref name="T"/> this instance holds, if it holds one.
+        /// </summary>
+        public bool TryGet<T>(out T value)
+        {
+            if (ActualInstance is T instance)
+            {
+                value = instance;
+                return true;
+            }
+
+            value = default;
+            return false;
+        }
+    }
 }