Adds global usings to generated code

Adds a global usings file to the generated code.

This reduces the amount of code needed in the generated files,
making them more readable and maintainable.

Author: arturcic

new-cli/GitVersion.Cli.Generator.Tests/SystemCommandlineGeneratorTests.cs

@@ -1,6 +1,7 @@
-using System.CommandLine;
+using System.CommandLine;
 using GitVersion.Infrastructure;
 using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Testing;
 using Microsoft.CodeAnalysis.Testing;
 
@@ -11,8 +12,6 @@ public class SystemCommandlineGeneratorTests
     /*language=cs*/
     private const string TestCommandSourceCode =
 """
-using System.Threading;
-using System.Threading.Tasks;
 using GitVersion.Infrastructure;
 
 namespace GitVersion.Commands;
@@ -32,6 +31,19 @@ public Task<int> InvokeAsync(TestCommandSettings settings, CancellationToken can
     }
 }
 
+""";
+
+    /*language=cs*/
+    private const string GlobalUsingsCode =
+"""
+// <autogenerated />
+global using global::System;
+global using global::System.Collections.Generic;
+global using global::System.IO;
+global using global::System.Linq;
+global using global::System.Net.Http;
+global using global::System.Threading;
+global using global::System.Threading.Tasks;
 """;
 
     /*language=cs*/
@@ -40,8 +52,6 @@ public Task<int> InvokeAsync(TestCommandSettings settings, CancellationToken can
 {{Content.GeneratedHeader}}
 using System.CommandLine;
 using System.CommandLine.Binding;
-using System.Threading;
-using System.Threading.Tasks;
 
 using GitVersion.Commands;
 
@@ -105,9 +115,7 @@ public void RegisterTypes(IContainerRegistrar services)
     private const string ExpectedRootCommandImplText =
 $$"""
 {{Content.GeneratedHeader}}
-using System.Collections.Generic;
 using System.CommandLine;
-using System.Linq;
 
 using GitVersion;
 namespace GitVersion.Generated;
@@ -147,6 +155,7 @@ public async Task ValidateGeneratedCommandImplementation()
             {
                 Sources =
                 {
+                    (generatorType, "GlobalUsings.cs", GlobalUsingsCode),
                     (generatorType, "TestCommand.cs", TestCommandSourceCode)
                 },
                 GeneratedSources =

new-cli/GitVersion.Cli.Generator/Content.cs

@@ -20,8 +20,6 @@ public static class Content
 {{{GeneratedHeader}}}
 using System.CommandLine;
 using System.CommandLine.Binding;
-using System.Threading;
-using System.Threading.Tasks;
 
 using {{Model.CommandTypeNamespace}};
 {{- if Model.SettingsTypeNamespace != Model.CommandTypeNamespace }}
@@ -78,9 +76,7 @@ Task<int> Run(ParseResult parseResult, CancellationToken cancellationToken)
     /*language=cs*/
     public const string RootCommandImplContent = $$$"""
 {{{GeneratedHeader}}}
-using System.Collections.Generic;
 using System.CommandLine;
-using System.Linq;
 
 using {{InfraNamespaceName}};
 namespace {{Namespace}};