Speed up builds with solution-level compile and output reuse

apps/Build.Abstractions/BuildContext.cs

@@ -88,6 +88,13 @@ public BuildContext(ICakeContext context)
 		/// </summary>
 		public MinVerVersion? Version { get; set; }
 
+		/// <summary>
+		/// Gets or sets whether the solution was compiled in this run.
+		/// When true, later test, pack, and publish steps can reuse outputs
+		/// without rebuilding project references.
+		/// </summary>
+		public bool SolutionBuilt { get; set; }
+
 		static (DirectoryPath, FilePath) GetRootPath(ICakeContext context, DirectoryPath path)
 		{
 			// Try and find the .git directory.

apps/Build.Abstractions/BuildHelpers.cs

@@ -12,12 +12,11 @@ namespace Build
 	using Cake.Common.IO;
 	using Cake.Common.Tools.DotNet;
 	using Cake.Common.Tools.DotNet.Build;
+	using Cake.Common.Tools.DotNet.MSBuild;
 	using Cake.Common.Tools.DotNet.Publish;
-	using Cake.Common.Tools.DotNet.Test;
 	using Cake.Common.Tools.MSBuild;
 	using Cake.Common.Tools.NuGet;
 	using Cake.Common.Tools.NuGet.Restore;
-	using Cake.Common.Tools.VSTest;
 	using Cake.Common.Xml;
 	using Cake.Core;
 	using Cake.Core.IO;
@@ -38,35 +37,44 @@ public static class BuildHelpers
 		};
 
 		/// <summary>
-		/// Builds the target project.
+		/// Builds or publishes the target project.
+		/// When <paramref name="publish"/> is set and the project has already been
+		/// built (for example by a solution-level compile), publish reuses those
+		/// outputs instead of rebuilding project references.
 		/// </summary>
 		/// <param name="context">The build context.</param>
 		/// <param name="project">The project to build.</param>
 		/// <param name="publish">States whether to publish the output.</param>
 		/// <param name="outputPath">The output path for publishing.</param>
+		/// <param name="noRestore">Skip restore when outputs are already restored.</param>
+		/// <param name="noDependencies">Skip building project references.</param>
 		public static void BuildProject(
 			this BuildContext context,
 			BuildProject project,
 			bool publish = false,
-			DirectoryPath? outputPath = default)
+			DirectoryPath? outputPath = default,
+			bool noRestore = false,
+			bool noDependencies = false)
 		{
 			context = context ?? throw new ArgumentNullException(nameof(context));
 			project = project ?? throw new ArgumentNullException(nameof(project));
 
+			bool reuseOutputs = project.HasBuilt || noDependencies;
+
 			if (project.BuildEngine == BuildEngine.MSBuild)
 			{
-				// MA - Force a NuGet restore
-				context.NuGetRestore(project.ProjectFilePath, new NuGetRestoreSettings());
+				if (!noRestore)
+				{
+					context.NuGetRestore(project.ProjectFilePath, new NuGetRestoreSettings());
+				}
 
 				var settings = new MSBuildSettings()
 				{
 					Configuration = context.Configuration,
+					MaxCpuCount = 0,
 					ArgumentCustomization = args =>
 					{
-						if (context.Version is not null)
-						{
-							args.Append($"/p:SemVer={context.Version}");
-						}
+						SolutionHelpers.ApplyCommonProperties(args, context, noDependencies || reuseOutputs);
 
 						if (publish && outputPath is not null)
 						{
@@ -80,11 +88,6 @@ public static void BuildProject(
 							}
 						}
 
-						if (context.SolutionPath is not null)
-						{
-							args.Append($"/p:SolutionDir={context.SolutionPath.FullPath}");
-						}
-
 						return args;
 					}
 				};
@@ -96,60 +99,59 @@ public static void BuildProject(
 
 				context.MSBuild(project.ProjectFilePath.FullPath, settings);
 			}
-			else
+			else if (publish && outputPath is not null)
 			{
 				foreach (string targetFramework in project.TargetFrameworks)
 				{
-					if (publish && outputPath is not null)
-					{
-						var settings = new DotNetPublishSettings()
-						{
-							Configuration = context.Configuration,
-							ArgumentCustomization = args =>
-							{
-								if (context.Version is not null)
-								{
-									args.Append($"/p:SemVer={context.Version}");
-								}
-
-								if (context.SolutionPath is not null)
-								{
-									args.Append($"/p:SolutionDir={context.SolutionPath.FullPath}");
-								}
-
-								return args;
-							},
-							Framework = targetFramework
-						};
-
-						context.DotNetPublish(project.ProjectFilePath.FullPath, settings);
-					}
-					else
+					var settings = new DotNetPublishSettings()
 					{
-						var settings = new DotNetBuildSettings()
-						{
-							Configuration = context.Configuration,
-							ArgumentCustomization = args =>
-							{
-								if (context.Version is not null)
-								{
-									args.Append($"/p:SemVer={context.Version}");
-								}
-
-								if (context.SolutionPath is not null)
-								{
-									args.Append($"/p:SolutionDir={context.SolutionPath.FullPath}");
-								}
-
-								return args;
-							},
-							Framework = targetFramework
-						};
-
-						context.DotNetBuild(project.ProjectFilePath.FullPath, settings);
-					}
+						Configuration = context.Configuration,
+						Framework = targetFramework,
+						OutputDirectory = outputPath,
+						NoBuild = reuseOutputs,
+						NoRestore = noRestore || reuseOutputs,
+						NoDependencies = noDependencies || reuseOutputs,
+						ArgumentCustomization = args => SolutionHelpers.ApplyCommonProperties(args, context, noDependencies || reuseOutputs)
+					};
+
+					context.DotNetPublish(project.ProjectFilePath.FullPath, settings);
 				}
 			}
+			else
+			{
+				var settings = new DotNetBuildSettings()
+				{
+					Configuration = context.Configuration,
+					NoRestore = noRestore,
+					NoDependencies = noDependencies,
+					MSBuildSettings = new DotNetMSBuildSettings
+					{
+						MaxCpuCount = 0
+					},
+					ArgumentCustomization = args => SolutionHelpers.ApplyCommonProperties(args, context, noDependencies)
+				};
+
+				context.DotNetBuild(project.ProjectFilePath.FullPath, settings);
+			}
+		}
+
+		/// <summary>
+		/// Gets discovered projects in the conventional build order:
+		/// libraries, applications, tests, data, then content.
+		/// </summary>
+		/// <param name="context">The build context.</param>
+		/// <returns>The ordered project list.</returns>
+		public static IReadOnlyList<BuildProject> GetProjectsInBuildOrder(this BuildContext context)
+		{
+			context = context ?? throw new ArgumentNullException(nameof(context));
+
+			var projects = new List<BuildProject>();
+			projects.AddRange(context.Projects[BuildType.Library]);
+			projects.AddRange(context.Projects[BuildType.Application]);
+			projects.AddRange(context.Projects[BuildType.Test]);
+			projects.AddRange(context.Projects[BuildType.Data]);
+			projects.AddRange(context.Projects[BuildType.Content]);
+			return projects;
 		}
 
 		/// <summary>

apps/Build.Abstractions/BuildServices.cs

@@ -4,7 +4,9 @@
 
 namespace Build
 {
+	using System;
 	using System.Collections.Generic;
+	using System.Linq;
 
 	using Microsoft.Extensions.DependencyInjection;
 
@@ -13,26 +15,26 @@ namespace Build
 	/// </summary>
 	public class BuildServices
 	{
-		readonly IServiceScopeFactory _serviceScopeFactory;
+		readonly IServiceProvider _services;
 
 		/// <summary>
 		/// Initialises a new instance of <see cref="BuildServices"/>
 		/// </summary>
-		/// <param name="hooks">The service scope factory.</param>
-		public BuildServices(IServiceScopeFactory serviceScopeFactory)
+		/// <param name="services">The root service provider.</param>
+		public BuildServices(IServiceProvider services)
 		{
-			_serviceScopeFactory = serviceScopeFactory;
+			_services = services;
 		}
 
 		/// <summary>
-		/// Gets the avilable hooks.
+		/// Gets the available hooks of the requested type.
+		/// Hooks are discovered from assemblies that reference this build
+		/// system and registered as <see cref="ITaskHook"/> implementations.
 		/// </summary>
 		/// <typeparam name="THook">The hook type.</typeparam>
 		/// <returns>The set of hooks.</returns>
 		public IEnumerable<THook> GetHooks<THook>()
 			where THook : ITaskHook
-		{
-			yield break;
-		}
+			=> _services.GetServices<ITaskHook>().OfType<THook>();
 	}
 }

apps/Build.Abstractions/Hooks/IBuildHook.cs

@@ -8,18 +8,23 @@ namespace Build
 
 	/// <summary>
 	/// Defines the required contract for implementing a build hook.
+	/// BeforeBuild runs for every project before the solution-level compile so
+	/// extensions can generate sources. AfterBuild runs after compile outputs
+	/// exist (including leftover projects not in the solution).
 	/// </summary>
 	public interface IBuildHook : ITaskHook
 	{
 		/// <summary>
-		/// Executes before the build starts.
+		/// Executes before the build starts for the given project.
+		/// Invoked before the solution-level compile.
 		/// </summary>
 		/// <param name="context">The build context.</param>
 		/// <param name="project">The build project.</param>
 		void BeforeBuild(BuildContext context, BuildProject project);
 
 		/// <summary>
-		/// Executes after the build completes.
+		/// Executes after the build completes for the given project.
+		/// Invoked after the solution-level compile and any leftover project builds.
 		/// </summary>
 		/// <param name="context">The build context.</param>
 		/// <param name="project">The build project.</param>
@@ -28,18 +33,22 @@ public interface IBuildHook : ITaskHook
 
 	/// <summary>
 	/// Defines the required contract for implementing an asynchronous build hook.
+	/// Hook phasing matches <see cref="IBuildHook"/>: all BeforeBuild callbacks
+	/// run before compile, all AfterBuild callbacks run after outputs exist.
 	/// </summary>
 	public interface IAsyncBuildHook : ITaskHook
 	{
 		/// <summary>
-		/// Executes before the build starts.
+		/// Executes before the build starts for the given project.
+		/// Invoked before the solution-level compile.
 		/// </summary>
 		/// <param name="context">The build context.</param>
 		/// <param name="project">The build project.</param>
 		Task BeforeBuildAsync(BuildContext context, BuildProject project);
 
 		/// <summary>
-		/// Executes after the build completes.
+		/// Executes after the build completes for the given project.
+		/// Invoked after the solution-level compile and any leftover project builds.
 		/// </summary>
 		/// <param name="context">The build context.</param>
 		/// <param name="project">The build project.</param>

apps/Build.Abstractions/PackHelpers.cs

@@ -61,7 +61,8 @@ public static void PackProject(
 					},
 					Configuration = context.Configuration,
 					OutputDirectory = context.ArtefactsPath,
-					NoBuild = project.HasBuilt
+					NoBuild = project.HasBuilt,
+					NoRestore = project.HasBuilt
 				});
 			}
 		}