Merge pull request #178 from mono/fix-incremental-build-test-race

Fix race in incremental build tests

Mono.TextTemplating.Build.Tests/MSBuildExecutionTests.cs

@@ -1,10 +1,7 @@
 // Copyright (c) Microsoft. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-using System;
-using System.IO;
 using System.Linq;
-
 using Xunit;
 
 namespace Mono.TextTemplating.Tests
@@ -154,23 +151,22 @@ void AssertNoopBuild ()
  AssertNoopBuild ();
 
  // check touching a template causes rebuild of that file only
- File.SetLastWriteTime (fooTemplate, DateTime.Now);
+ WriteTimeTracker.SetWriteTimeNewerThan (barWriteTime, barTemplate);
  ExecuteAndValidate ();
- fooWriteTime.AssertChanged ();
- barWriteTime.AssertSame ();
+ fooWriteTime.AssertSame ();
+ barWriteTime.AssertChanged ();
 
  AssertNoopBuild ();
 
  // check touching the include causes rebuild of the file that uses it
- File.SetLastWriteTime (includeFile, DateTime.Now);
+ WriteTimeTracker.SetWriteTimeNewerThan (fooWriteTime, includeFile);
  ExecuteAndValidate ();
  fooWriteTime.AssertChanged ();
  barWriteTime.AssertSame ();
 
  AssertNoopBuild ();
 
  // check changing a parameter causes rebuild of both files
- File.SetLastWriteTime (includeFile, DateTime.Now);
  project.Project.GetItems ("T4Argument").Single (i => i.UnevaluatedInclude == "Year").SetMetadataValue ("Value", "2021");
  ExecuteAndValidate ();
  fooGenerated.AssertTextStartsWith ("Helper says Hello 2021!");

Mono.TextTemplating.Build.Tests/Mono.TextTemplating.Build.Tests.csproj

@@ -34,6 +34,7 @@
  <None Include="TestCases\**\*.*" />
  <Compile Include="..\Mono.TextTemplating.Tests\Platform.cs" />
  <Compile Include="..\Mono.TextTemplating.Tests\TestDataPath.cs" />
+ <Compile Include="..\Mono.TextTemplating.Tests\WriteTimeTracker.cs" />
  </ItemGroup>
 
 </Project>

Mono.TextTemplating.Tests/TestDataPath.cs

@@ -147,15 +147,6 @@ public DateTime AssertWriteTimeNewerThan (DateTime previousWriteTime)
  }
 }
 
-sealed class WriteTimeTracker
-{
- readonly TestDataPath file;
- DateTime lastWriteTime;
- public WriteTimeTracker (TestDataPath file) => lastWriteTime = (this.file = file).GetLastWriteTime ();
- public void AssertChanged () => lastWriteTime = file.AssertWriteTimeNewerThan (lastWriteTime);
- public void AssertSame () => file.AssertWriteTimeEquals (lastWriteTime);
-}
-
 static class StringNormalizationExtensions
 {
  public static string NormalizeNewlines (this string s, string newLine = "\n") => s.Replace ("\r\n", "\n").Replace ("\n", newLine);

Mono.TextTemplating.Tests/WriteTimeTracker.cs

@@ -0,0 +1,65 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Threading;
+
+namespace Mono.TextTemplating.Tests;
+
+sealed class WriteTimeTracker
+{
+ readonly TestDataPath file;
+ DateTime lastWriteTime;
+ public WriteTimeTracker (TestDataPath file) => lastWriteTime = (this.file = file).GetLastWriteTime ();
+ public void AssertChanged () => lastWriteTime = file.AssertWriteTimeNewerThan (lastWriteTime);
+ public void AssertSame () => file.AssertWriteTimeEquals (lastWriteTime);
+
+ public DateTime WaitUntilLaterNow () => LaterNowThan (lastWriteTime);
+
+ static DateTime GetNewestWriteTime (IEnumerable<WriteTimeTracker> trackers)
+ {
+ DateTime newest = DateTime.MinValue;
+ foreach (var tracker in trackers) {
+ if (newest < tracker.lastWriteTime) {
+ newest = tracker.lastWriteTime;
+ }
+ }
+ return newest;
+ }
+
+ public static void SetWriteTimeNewerThan (IEnumerable<WriteTimeTracker> trackers, string filePath)
+ => SetWriteTimeNewerThan (GetNewestWriteTime (trackers), filePath);
+
+ public static void SetWriteTimeNewerThan (WriteTimeTracker tracker, string filePath)
+ => SetWriteTimeNewerThan (tracker.lastWriteTime, filePath);
+
+ public static void SetWriteTimeNewerThan (IEnumerable<WriteTimeTracker> trackers, params string[] filePaths)
+ => SetWriteTimeNewerThan (GetNewestWriteTime (trackers), filePaths);
+
+ public static void SetWriteTimeNewerThan (WriteTimeTracker tracker, params string[] filePaths)
+ => SetWriteTimeNewerThan (tracker.lastWriteTime, filePaths);
+
+ /// <summary>
+ /// Waits until `DateTime.Now` is newer than `time`, then return this newer value.
+ /// </summary>
+ static DateTime LaterNowThan (DateTime time)
+ {
+ DateTime now;
+ while ((now = DateTime.Now) <= time) {
+ Thread.Sleep (10);
+ }
+ return now;
+ }
+
+ static void SetWriteTimeNewerThan (DateTime time, string filePath) => File.SetLastWriteTime (filePath, LaterNowThan (time));
+
+ static void SetWriteTimeNewerThan (DateTime time, params string[] filePaths)
+ {
+ var now = LaterNowThan (time);
+ foreach (var file in filePaths) {
+ File.SetLastWriteTime (file, now);
+ }
+ }
+}