2

Author: tmat

src/BuiltInTools/dotnet-watch/EvaluationResult.cs

@@ -15,8 +15,8 @@ internal sealed class EvaluationResult(IReadOnlyDictionary<string, FileItem> fil
     private readonly Lazy<IReadOnlySet<string>> _lazyBuildFiles = new(() => projectGraph != null ? CreateBuildFileSet(projectGraph) : new HashSet<string>());
 
     public static IReadOnlySet<string> CreateBuildFileSet(ProjectGraph projectGraph)
-        => projectGraph.ProjectNodes
-            .SelectMany(p => p.ProjectInstance.ImportPaths)
+        => projectGraph.ProjectNodes.SelectMany(p => p.ProjectInstance.ImportPaths)
+            .Concat(projectGraph.ProjectNodes.Select(p => p.ProjectInstance.FullPath))
             .ToHashSet(PathUtilities.OSSpecificPathComparer);
 
     public IReadOnlySet<string> BuildFiles => _lazyBuildFiles.Value;

src/BuiltInTools/dotnet-watch/HotReload/FilePathExclusions.cs

@@ -70,9 +70,9 @@ void TryAddOutputDir(string? dir)
 
     public void Report(IReporter reporter)
     {
-        foreach (var (_, value, projectDir) in exclusionGlobs)
+        foreach (var globsPerDirectory in exclusionGlobs.GroupBy(keySelector: static g => g.projectDir, elementSelector: static g => g.value))
         {
-            reporter.Verbose($"Exclusion glob: '{value}' under project '{projectDir}'");
+            reporter.Verbose($"Exclusion glob: '{string.Join(";", globsPerDirectory)}' under project '{globsPerDirectory.Key}'");
         }
 
         foreach (var dir in outputDirectories)

src/BuiltInTools/dotnet-watch/Internal/MsBuildFileSetFactory.cs

@@ -1,8 +1,12 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Collections.Concurrent;
 using System.Diagnostics;
 using System.Text.Json;
+using Microsoft.Build.Evaluation;
+using Microsoft.Build.Execution;
+using Microsoft.Build.FileSystem;
 using Microsoft.Build.Graph;
 
 namespace Microsoft.DotNet.Watch
@@ -120,7 +124,7 @@ void AddFile(string filePath, string? staticWebAssetPath)
                 ProjectGraph? projectGraph = null;
                 if (requireProjectGraph != null)
                 {
-                    projectGraph = TryLoadProjectGraph(requireProjectGraph.Value);
+                    projectGraph = TryLoadProjectGraph(requireProjectGraph.Value, cancellationToken);
                     if (projectGraph == null && requireProjectGraph == true)
                     {
                         return null;
@@ -193,7 +197,11 @@ private static string FindTargetsFile()
         }
 
         // internal for testing
-        internal ProjectGraph? TryLoadProjectGraph(bool projectGraphRequired)
+
+        /// <summary>
+        /// Tries to create a project graph by running the build evaluation phase on the <see cref="rootProjectFile"/>.
+        /// </summary>
+        internal ProjectGraph? TryLoadProjectGraph(bool projectGraphRequired, CancellationToken cancellationToken)
         {
             var globalOptions = new Dictionary<string, string>();
 
@@ -202,9 +210,11 @@ private static string FindTargetsFile()
                 globalOptions[name] = value;
             }
 
+            var entryPoint = new ProjectGraphEntryPoint(rootProjectFile, globalOptions);
+
             try
             {
-                return new ProjectGraph(rootProjectFile, globalOptions);
+                return new ProjectGraph([entryPoint], ProjectCollection.GlobalProjectCollection, projectInstanceFactory: null, cancellationToken);
             }
             catch (Exception e)
             {

src/BuiltInTools/dotnet-watch/Properties/launchSettings.json

@@ -3,7 +3,7 @@
     "dotnet-watch": {
       "commandName": "Project",
       "commandLineArgs": "--verbose /bl:DotnetRun.binlog",
-      "workingDirectory": "C:\\Temp\\app\\dir",
+      "workingDirectory": "C:\\sdk4\\artifacts\\tmp\\Debug\\ProjectChange---0B95B003\\AppWithDeps",
       "environmentVariables": {
         "DOTNET_WATCH_DEBUG_SDK_DIRECTORY": "$(RepoRoot)artifacts\\bin\\redist\\$(Configuration)\\dotnet\\sdk\\$(Version)",
         "DCP_IDE_REQUEST_TIMEOUT_SECONDS": "100000",

test/TestAssets/TestProjects/WatchAppWithProjectDeps/AppWithDeps/Program.cs

@@ -20,7 +20,7 @@ public static void Main(string[] args)
             while (true)
             {
                 Lib.Print();
-                Thread.Sleep(10);
+                Thread.Sleep(1000);
             }
         }
     }

test/TestAssets/TestProjects/WatchAppWithProjectDeps/Dependency/Dependency.csproj

@@ -3,6 +3,7 @@
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(CurrentTargetFramework)</TargetFrameworks>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <DefineConstants>$(DefineConstants);BUILD_CONST_IN_CSPROJ</DefineConstants>
   </PropertyGroup>
 
 </Project>

test/TestAssets/TestProjects/WatchAppWithProjectDeps/Directory.Build.props

@@ -1,6 +1,6 @@
 <Project>
   <PropertyGroup>
     <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
-    <DefineConstants>$(DefineConstants);BUILD_CONST</DefineConstants>
+    <DefineConstants>$(DefineConstants);BUILD_CONST_IN_PROPS</DefineConstants>
   </PropertyGroup>
 </Project>

test/dotnet-watch.Tests/HotReload/ApplyDeltaTests.cs

@@ -105,14 +105,63 @@ public static unsafe void Print()
             await App.WaitUntilOutputContains($"dotnet watch 🔥 [App.WithDeps ({ToolsetInfo.CurrentTargetFramework})] Hot reload succeeded.");
         }
 
-        [Fact]
-        public async Task ProjectChange_DirectoryBuildProps_Update()
+        [Theory]
+        [CombinatorialData]
+        public async Task ProjectChange_Update(bool isDirectoryProps)
+        {
+            var testAsset = TestAssets.CopyTestAsset("WatchAppWithProjectDeps", identifier: isDirectoryProps.ToString())
+                .WithSource();
+
+            var symbolName = isDirectoryProps ? "BUILD_CONST_IN_PROPS" : "BUILD_CONST_IN_CSPROJ";
+
+            var dependencyDir = Path.Combine(testAsset.Path, "Dependency");
+            var libSourcePath = Path.Combine(dependencyDir, "Foo.cs");
+            var buildFilePath = isDirectoryProps ? Path.Combine(testAsset.Path, "Directory.Build.props") : Path.Combine(dependencyDir, "Dependency.csproj");
+
+            File.WriteAllText(libSourcePath, $$"""
+                public class Lib
+                {
+                    public static void Print()
+                    {
+                #if {{symbolName}}
+                        System.Console.WriteLine("{{symbolName}} set");
+                #else
+                        System.Console.WriteLine("{{symbolName}} not set");
+                #endif
+                    }
+                }
+                """);
+
+            App.Start(testAsset, [], "AppWithDeps");
+
+            await App.AssertWaitingForChanges();
+            await App.WaitUntilOutputContains($"{symbolName} set");
+            App.Process.ClearOutput();
+
+            UpdateSourceFile(buildFilePath, src => src.Replace(symbolName, ""));
+
+            // TODO: https://github.com/dotnet/roslyn/issues/78921
+
+            // Roslyn should detect change in build constant and apply it or flag it as rude edit.
+            //await App.WaitUntilOutputContains($"dotnet watch 🔥 [App.WithDeps ({ToolsetInfo.CurrentTargetFramework})] Hot reload succeeded.");
+            //await App.WaitUntilOutputContains("BUILD_CONST not set");
+
+            await App.AssertOutputLineStartsWith(MessageDescriptor.NoCSharpChangesToApply);
+            App.AssertOutputContains(MessageDescriptor.ProjectChangeTriggeredReEvaluation);
+        }
+
+        [Fact(Skip = "https://github.com/dotnet/msbuild/issues/12001")]
+        public async Task ProjectChange_DirectoryBuildProps_Add()
         {
             var testAsset = TestAssets.CopyTestAsset("WatchAppWithProjectDeps")
                 .WithSource();
 
             var dependencyDir = Path.Combine(testAsset.Path, "Dependency");
             var libSourcePath = Path.Combine(dependencyDir, "Foo.cs");
+            var directoryBuildProps = Path.Combine(testAsset.Path, "Directory.Build.props");
+
+            // delete the file before we start the app, it will be added later:
+            File.Delete(directoryBuildProps);
 
             File.WriteAllText(libSourcePath, """
                 public class Lib
@@ -133,17 +182,16 @@ public static void Print()
 
             await App.AssertWaitingForChanges();
             await App.WaitUntilOutputContains("BUILD_CONST set");
+            App.Process.ClearOutput();
 
             UpdateSourceFile(
-                Path.Combine(testAsset.Path, "Directory.Build.props"),
+                directoryBuildProps,
                 src => src.Replace("BUILD_CONST", ""));
 
-            //await App.AssertOutputLineStartsWith(MessageDescriptor.NoCSharpChangesToApply);
-            //App.AssertOutputContains(MessageDescriptor.ProjectChangeTriggeredReEvaluation);
-            //App.Process.ClearOutput();
-
-            await App.AssertOutputLineStartsWith("BUILD_CONST not set");
             await App.WaitUntilOutputContains($"dotnet watch 🔥 [App.WithDeps ({ToolsetInfo.CurrentTargetFramework})] Hot reload succeeded.");
+            await App.WaitUntilOutputContains("BUILD_CONST not set");
+
+            App.AssertOutputContains(MessageDescriptor.ProjectChangeTriggeredReEvaluation);
         }
 
         [Fact]

test/dotnet-watch.Tests/HotReload/CompilationHandlerTests.cs

@@ -26,7 +26,7 @@ public async Task ReferenceOutputAssembly_False()
             environmentOptions: environmentOptions,
             reporter);
 
-        var projectGraph = factory.TryLoadProjectGraph(projectGraphRequired: false);
+        var projectGraph = factory.TryLoadProjectGraph(projectGraphRequired: false, CancellationToken.None);
         var handler = new CompilationHandler(reporter, environmentOptions, CancellationToken.None);
 
         await handler.Workspace.UpdateProjectConeAsync(hostProject, CancellationToken.None);