Use compound assignment (#186)

* Used compound assignment

* -||-

* -||-

samples/02_commands_framework/Modules/PublicModule.cs

@@ -31,7 +31,7 @@ namespace _02_commands_framework.Modules
         [Command("userinfo")]
         public async Task UserInfoAsync(IUser user = null)
         {
-            user = user ?? Context.User;
+            user ??= Context.User;
 
             await ReplyAsync(user.ToString());
         }

src/Discord.Net.Commands/Builders/ModuleClassBuilder.cs

@@ -116,7 +116,7 @@ namespace Discord.Commands
                         builder.AddAliases(alias.Aliases);
                         break;
                     case GroupAttribute group:
-                        builder.Name = builder.Name ?? group.Prefix;
+                        builder.Name ??= group.Prefix;
                         builder.Group = group.Prefix;
                         builder.AddAliases(group.Prefix);
                         break;
@@ -158,7 +158,7 @@ namespace Discord.Commands
                     case CommandAttribute command:
                         builder.AddAliases(command.Text);
                         builder.RunMode = command.RunMode;
-                        builder.Name = builder.Name ?? command.Text;
+                        builder.Name ??= command.Text;
                         builder.IgnoreExtraArgs = command.IgnoreExtraArgs ?? service._ignoreExtraArgs;
                         break;
                     case NameAttribute name:

src/Discord.Net.Commands/Builders/ParameterBuilder.cs

@@ -131,7 +131,7 @@ namespace Discord.Commands.Builders
 
         internal ParameterInfo Build(CommandInfo info)
         {
-            if ((TypeReader ?? (TypeReader = GetReader(ParameterType))) == null)
+            if ((TypeReader ??= GetReader(ParameterType)) == null)
                 throw new InvalidOperationException($"No type reader found for type {ParameterType.Name}, one must be specified");
 
             return new ParameterInfo(this, info, Command.Module.Service);

src/Discord.Net.Commands/CommandService.cs

@@ -189,7 +189,7 @@ namespace Discord.Commands
         /// </returns>
         public async Task<ModuleInfo> AddModuleAsync(Type type, IServiceProvider services)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             await _moduleLock.WaitAsync().ConfigureAwait(false);
             try
@@ -224,7 +224,7 @@ namespace Discord.Commands
         /// </returns>
         public async Task<IEnumerable<ModuleInfo>> AddModulesAsync(Assembly assembly, IServiceProvider services)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             await _moduleLock.WaitAsync().ConfigureAwait(false);
             try
@@ -507,7 +507,7 @@ namespace Discord.Commands
         /// </returns>
         public async Task<IResult> ExecuteAsync(ICommandContext context, string input, IServiceProvider services, MultiMatchHandling multiMatchHandling = MultiMatchHandling.Exception)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             var searchResult = Search(input);
             if (!searchResult.IsSuccess)

src/Discord.Net.Commands/Info/CommandInfo.cs

@@ -123,7 +123,7 @@ namespace Discord.Commands
 
         public async Task<PreconditionResult> CheckPreconditionsAsync(ICommandContext context, IServiceProvider services = null)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             async Task<PreconditionResult> CheckGroups(IEnumerable<PreconditionAttribute> preconditions, string type)
             {
@@ -164,7 +164,7 @@ namespace Discord.Commands
 
         public async Task<ParseResult> ParseAsync(ICommandContext context, int startIndex, SearchResult searchResult, PreconditionResult preconditionResult = null, IServiceProvider services = null)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             if (!searchResult.IsSuccess)
                 return ParseResult.FromError(searchResult);
@@ -201,7 +201,7 @@ namespace Discord.Commands
         }
         public async Task<IResult> ExecuteAsync(ICommandContext context, IEnumerable<object> argList, IEnumerable<object> paramList, IServiceProvider services)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             try
             {

src/Discord.Net.Commands/Info/ParameterInfo.cs

@@ -75,7 +75,7 @@ namespace Discord.Commands
 
         public async Task<PreconditionResult> CheckPreconditionsAsync(ICommandContext context, object arg, IServiceProvider services = null)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
 
             foreach (var precondition in Preconditions)
             {
@@ -89,7 +89,7 @@ namespace Discord.Commands
 
         public async Task<TypeReaderResult> ParseAsync(ICommandContext context, string input, IServiceProvider services = null)
         {
-            services = services ?? EmptyServiceProvider.Instance;
+            services ??= EmptyServiceProvider.Instance;
             return await _reader.ReadAsync(context, input, services).ConfigureAwait(false);
         }
 

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -177,7 +177,7 @@ namespace Discord.API
         public async Task SendAsync(string method, string endpoint,
             BucketId bucketId = null, ClientBucketType clientBucket = ClientBucketType.Unbucketed, RequestOptions options = null)
         {
-            options = options ?? new RequestOptions();
+            options ??= new RequestOptions();
             options.HeaderOnly = true;
             options.BucketId = bucketId;
 
@@ -191,7 +191,7 @@ namespace Discord.API
         public async Task SendJsonAsync(string method, string endpoint, object payload,
             BucketId bucketId = null, ClientBucketType clientBucket = ClientBucketType.Unbucketed, RequestOptions options = null)
         {
-            options = options ?? new RequestOptions();
+            options ??= new RequestOptions();
             options.HeaderOnly = true;
             options.BucketId = bucketId;
 
@@ -206,7 +206,7 @@ namespace Discord.API
         public async Task SendMultipartAsync(string method, string endpoint, IReadOnlyDictionary<string, object> multipartArgs,
             BucketId bucketId = null, ClientBucketType clientBucket = ClientBucketType.Unbucketed, RequestOptions options = null)
         {
-            options = options ?? new RequestOptions();
+            options ??= new RequestOptions();
             options.HeaderOnly = true;
             options.BucketId = bucketId;
 
@@ -220,7 +220,7 @@ namespace Discord.API
         public async Task<TResponse> SendAsync<TResponse>(string method, string endpoint,
             BucketId bucketId = null, ClientBucketType clientBucket = ClientBucketType.Unbucketed, RequestOptions options = null) where TResponse : class
         {
-            options = options ?? new RequestOptions();
+            options ??= new RequestOptions();
             options.BucketId = bucketId;
 
             var request = new RestRequest(RestClient, method, endpoint, options);
@@ -233,7 +233,7 @@ namespace Discord.API
         public async Task<TResponse> SendJsonAsync<TResponse>(string method, string endpoint, object payload,
             BucketId bucketId = null, ClientBucketType clientBucket = ClientBucketType.Unbucketed, RequestOptions options = null) where TResponse : class
         {
-            options = options ?? new RequestOptions();
+            options ??= new RequestOptions();
             options.BucketId = bucketId;
 
             string json = payload != null ? SerializeJson(payload) : null;
@@ -248,7 +248,7 @@ namespace Discord.API
         public async Task<TResponse> SendMultipartAsync<TResponse>(string method, string endpoint, IReadOnlyDictionary<string, object> multipartArgs,
             BucketId bucketId = null, ClientBucketType clientBucket = ClientBucketType.Unbucketed, RequestOptions options = null)
         {
-            options = options ?? new RequestOptions();
+            options ??= new RequestOptions();
             options.BucketId = bucketId;
 
             var request = new MultipartRestRequest(RestClient, method, endpoint, multipartArgs, options);

src/Discord.Net.Rest/DiscordRestClient.cs

@@ -62,7 +62,7 @@ namespace Discord.Rest
 
         public async Task<RestApplication> GetApplicationInfoAsync(RequestOptions options = null)
         {
-            return _applicationInfo ?? (_applicationInfo = await ClientHelper.GetApplicationInfoAsync(this, options).ConfigureAwait(false));
+            return _applicationInfo ??= await ClientHelper.GetApplicationInfoAsync(this, options).ConfigureAwait(false);
         }
 
         public Task<RestChannel> GetChannelAsync(ulong id, RequestOptions options = null)

src/Discord.Net.Rest/Entities/Messages/MessageHelper.cs

@@ -344,7 +344,7 @@ namespace Discord.Rest
                     tags.Add(new Tag<Emote>(TagType.Emoji, index, content.Length, emoji.Id, emoji));
                 else //Bad Tag
                 {
-                    index = index + 1;
+                    index++;
                     continue;
                 }
                 index = endIndex + 1;

src/Discord.Net.WebSocket/DiscordSocketClient.cs

@@ -322,7 +322,7 @@ namespace Discord.WebSocket
 
         /// <inheritdoc />
         public override async Task<RestApplication> GetApplicationInfoAsync(RequestOptions options = null)
-            => _applicationInfo ?? (_applicationInfo = await ClientHelper.GetApplicationInfoAsync(this, options ?? RequestOptions.Default).ConfigureAwait(false));
+            => _applicationInfo ??= await ClientHelper.GetApplicationInfoAsync(this, options ?? RequestOptions.Default).ConfigureAwait(false);
 
         /// <inheritdoc />
         public override SocketGuild GetGuild(ulong id)

test/Discord.Net.Analyzers.Tests/Helpers/DiagnosticVerifier.Helper.cs

@@ -187,7 +187,7 @@ namespace TestHelper
 
         private static HashSet<Assembly> RecursiveReferencedAssemblies(Assembly a, HashSet<Assembly> assemblies = null)
         {
-            assemblies = assemblies ?? new HashSet<Assembly>();
+            assemblies ??= new HashSet<Assembly>();
             if (assemblies.Add(a))
             {
                 foreach (var referencedAssemblyName in a.GetReferencedAssemblies())