Improve output reporting, fix potential race condition of output redirection

Author: tmat

src/BuiltInTools/dotnet-watch/HotReloadDotNetWatcher.cs

@@ -119,9 +119,10 @@ public override async Task WatchAsync(CancellationToken shutdownCancellationToke
                         };
                     }
 
-                    if (!await BuildProjectAsync(rootProjectOptions.ProjectPath, rootProjectOptions.BuildArguments, iterationCancellationToken))
+                    var (buildSucceeded, buildOutput, _) = await BuildProjectAsync(rootProjectOptions.ProjectPath, rootProjectOptions.BuildArguments, iterationCancellationToken);
+                    BuildUtilities.ReportBuildOutput(Context.Reporter, buildOutput, buildSucceeded, projectDisplay: rootProjectOptions.ProjectPath);
+                    if (!buildSucceeded)
                     {
-                        // error has been reported:
                         continue;
                     }
 
@@ -325,7 +326,12 @@ void FileChangedCallback(string path, ChangeKind kind)
                                     var buildResults = await Task.WhenAll(
                                         projectsToRebuild.Values.Select(projectPath => BuildProjectAsync(projectPath, rootProjectOptions.BuildArguments, iterationCancellationToken)));
 
-                                    if (buildResults.All(success => success))
+                                    foreach (var (success, output, projectPath) in buildResults)
+                                    {
+                                        BuildUtilities.ReportBuildOutput(Context.Reporter, output, success, projectPath);
+                                    }
+
+                                    if (buildResults.All(result => result.success))
                                     {
                                         break;
                                     }
@@ -675,7 +681,8 @@ await FileWatcher.WaitForFileChangeAsync(
             }
         }
 
-        private async Task<bool> BuildProjectAsync(string projectPath, IReadOnlyList<string> buildArguments, CancellationToken cancellationToken)
+        private async Task<(bool success, ImmutableArray<OutputLine> output, string projectPath)> BuildProjectAsync(
+            string projectPath, IReadOnlyList<string> buildArguments, CancellationToken cancellationToken)
         {
             var buildOutput = new List<OutputLine>();
 
@@ -694,17 +701,10 @@ private async Task<bool> BuildProjectAsync(string projectPath, IReadOnlyList<str
                 Arguments = ["build", projectPath, "-consoleLoggerParameters:NoSummary;Verbosity=minimal", .. buildArguments]
             };
 
-            Context.Reporter.Output($"Building '{projectPath}' ...");
+            Context.Reporter.Output($"Building {projectPath} ...");
 
             var exitCode = await ProcessRunner.RunAsync(processSpec, Context.Reporter, isUserApplication: false, launchResult: null, cancellationToken);
-            BuildUtilities.ReportBuildOutput(Context.Reporter, buildOutput, verboseOutput: exitCode == 0);
-
-            if (exitCode == 0)
-            {
-                Context.Reporter.Output("Build succeeded.");
-            }
-
-            return exitCode == 0;
+            return (exitCode == 0, buildOutput.ToImmutableArray(), projectPath);
         }
 
         private string GetRelativeFilePath(string path)

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

@@ -63,7 +63,7 @@ internal class MSBuildFileSetFactory(
                     reporter.Output($"MSBuild output from target '{TargetName}':");
                 }
 
-                BuildUtilities.ReportBuildOutput(reporter, capturedOutput, verboseOutput: success);
+                BuildUtilities.ReportBuildOutput(reporter, capturedOutput, success, projectDisplay: null);
                 if (!success)
                 {
                     return null;

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

@@ -87,6 +87,15 @@ public static async Task<int> RunAsync(ProcessSpec processSpec, IReporter report
                 try
                 {
                     await process.WaitForExitAsync(processTerminationToken);
+
+                    // ensures that all process output has been reported:
+                    try
+                    {
+                        process.WaitForExit();
+                    }
+                    catch
+                    {
+                    }
                 }
                 catch (OperationCanceledException)
                 {

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

@@ -3,7 +3,7 @@
     "dotnet-watch": {
       "commandName": "Project",
       "commandLineArgs": "--verbose /bl:DotnetRun.binlog",
-      "workingDirectory": "$(RepoRoot)src\\Assets\\TestProjects\\BlazorWasmWithLibrary\\blazorwasm",
+      "workingDirectory": "C:\\sdk5\\artifacts\\tmp\\Debug\\Aspire_ApplyD---C6DC4E42\\WatchAspire.AppHost",
       "environmentVariables": {
         "DOTNET_WATCH_DEBUG_SDK_DIRECTORY": "$(RepoRoot)artifacts\\bin\\redist\\$(Configuration)\\dotnet\\sdk\\$(Version)",
         "DCP_IDE_REQUEST_TIMEOUT_SECONDS": "100000",

src/BuiltInTools/dotnet-watch/Utilities/BuildUtilities.cs

@@ -7,14 +7,25 @@ namespace Microsoft.DotNet.Watch;
 
 internal static partial class BuildUtilities
 {
+    private const string BuildEmoji = "🔨";
     private static readonly Regex s_buildDiagnosticRegex = GetBuildDiagnosticRegex();
 
     [GeneratedRegex(@"[^:]+: (error|warning) [A-Za-z]+[0-9]+: .+")]
     private static partial Regex GetBuildDiagnosticRegex();
 
-    public static void ReportBuildOutput(IReporter reporter, IEnumerable<OutputLine> buildOutput, bool verboseOutput)
+    public static void ReportBuildOutput(IReporter reporter, IEnumerable<OutputLine> buildOutput, bool success, string? projectDisplay)
     {
-        const string BuildEmoji = "🔨";
+        if (projectDisplay != null)
+        {
+            if (success)
+            {
+                reporter.Output($"Build succeeded: {projectDisplay}", BuildEmoji);
+            }
+            else
+            {
+                reporter.Output($"Build failed: {projectDisplay}", BuildEmoji);
+            }
+        }
 
         foreach (var (line, isError) in buildOutput)
         {
@@ -33,7 +44,7 @@ public static void ReportBuildOutput(IReporter reporter, IEnumerable<OutputLine>
                     reporter.Warn(line);
                 }
             }
-            else if (verboseOutput)
+            else if (success)
             {
                 reporter.Verbose(line, BuildEmoji);
             }

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

@@ -637,7 +637,7 @@ public async Task Aspire()
                 App.AssertOutputContains($"[WatchAspire.ApiService ({tfm})] Exited");
             }
 
-            App.AssertOutputContains($"dotnet watch ⌚ Building '{serviceProjectPath}' ...");
+            App.AssertOutputContains($"dotnet watch ⌚ Building {serviceProjectPath} ...");
             App.AssertOutputContains("error CS0246: The type or namespace name 'WeatherForecast' could not be found");
             App.Process.ClearOutput();
 
@@ -648,7 +648,7 @@ public async Task Aspire()
 
             await App.AssertOutputLineStartsWith($"dotnet watch ⌚ [WatchAspire.ApiService ({tfm})] Capabilities");
 
-            App.AssertOutputContains("dotnet watch ⌚ Build succeeded.");
+            App.AssertOutputContains($"dotnet watch 🔨 Build succeeded: {serviceProjectPath}");
             App.AssertOutputContains("dotnet watch 🔥 Project baselines updated.");
             App.AssertOutputContains($"dotnet watch ⭐ Starting project: {serviceProjectPath}");
 

test/dotnet-watch.Tests/Utilities/AwaitableProcess.cs

@@ -129,7 +129,7 @@ private void OnData(object sender, DataReceivedEventArgs args)
                 line = line.StripTerminalLoggerProgressIndicators();
             }
 
-            WriteTestOutput($"{DateTime.Now}: post: '{line}'");
+            WriteTestOutput(line);
             _source.Post(line);
         }