Fix flaky WriteWithoutClose/CreateFileWithoutClose functional tests

GVFS/GVFS.FunctionalTests/FileSystemRunners/BashRunner.cs

@@ -304,12 +304,12 @@ public override long FileSize(string path)
             return long.Parse(this.RunProcess(statCommand));
         }
 
-        public override void CreateFileWithoutClose(string path)
+        public override IDisposable CreateFileWithoutClose(string path)
         {
             throw new NotImplementedException();
         }
 
-        public override void OpenFileAndWriteWithoutClose(string path, string data)
+        public override IDisposable OpenFileAndWriteWithoutClose(string path, string data)
         {
             throw new NotImplementedException();
         }

GVFS/GVFS.FunctionalTests/FileSystemRunners/CmdRunner.cs

@@ -238,12 +238,12 @@ public override void ChangeMode(string path, ushort mode)
             throw new NotSupportedException();
         }
 
-        public override void CreateFileWithoutClose(string path)
-        {
+        public override IDisposable CreateFileWithoutClose(string path)
+        {
             throw new NotImplementedException();
-        }
-
-        public override void OpenFileAndWriteWithoutClose(string path, string data)
+        }
+
+        public override IDisposable OpenFileAndWriteWithoutClose(string path, string data)
         {
             throw new NotImplementedException();
         }

GVFS/GVFS.FunctionalTests/FileSystemRunners/FileSystemRunner.cs

@@ -76,8 +76,8 @@ public static FileSystemRunner DefaultRunner
         /// <param name="path">Path to file</param>
         /// <param name="contents">File contents</param>
         public abstract void WriteAllText(string path, string contents);
-        public abstract void CreateFileWithoutClose(string path);
-        public abstract void OpenFileAndWriteWithoutClose(string path, string data);
+        public abstract IDisposable CreateFileWithoutClose(string path);
+        public abstract IDisposable OpenFileAndWriteWithoutClose(string path, string data);
 
         /// <summary>
         /// Append the specified contents to the specified file.  By calling this method the caller is

GVFS/GVFS.FunctionalTests/FileSystemRunners/PowerShellRunner.cs

@@ -1,4 +1,5 @@
 using GVFS.Tests.Should;
+using System;
 using System.IO;
 
 namespace GVFS.FunctionalTests.FileSystemRunners
@@ -217,12 +218,12 @@ public override void ChangeMode(string path, ushort mode)
             throw new System.NotSupportedException();
         }
 
-        public override void CreateFileWithoutClose(string path)
+        public override IDisposable CreateFileWithoutClose(string path)
         {
             throw new System.NotSupportedException();
-        }
-
-        public override void OpenFileAndWriteWithoutClose(string path, string data)
+        }
+
+        public override IDisposable OpenFileAndWriteWithoutClose(string path, string data)
         {
             throw new System.NotSupportedException();
         }

GVFS/GVFS.FunctionalTests/FileSystemRunners/SystemIORunner.cs

@@ -22,15 +22,17 @@ public override string MoveFile(string sourcePath, string targetPath)
             return string.Empty;
         }
 
-        public override void CreateFileWithoutClose(string path)
+        public override IDisposable CreateFileWithoutClose(string path)
         {
-            File.Create(path);
-        }
-
-        public override void OpenFileAndWriteWithoutClose(string path, string content)
+            return File.Create(path);
+        }
+
+        public override IDisposable OpenFileAndWriteWithoutClose(string path, string content)
         {
             StreamWriter file = new StreamWriter(path);
             file.Write(content);
+            file.Flush();
+            return file;
         }
 
         public override void MoveFileShouldFail(string sourcePath, string targetPath)

GVFS/GVFS.FunctionalTests/Tests/GitCommands/GitRepoTests.cs

@@ -326,22 +326,24 @@ protected void CreateFile(string content, params string[] filePathPaths)
             this.FileSystem.WriteAllText(controlFile, content);
         }
 
-        protected void CreateFileWithoutClose(string path)
-        {
+        protected IDisposable CreateFileWithoutClose(string path)
+        {
             string virtualFile = Path.Combine(this.Enlistment.RepoRoot, path);
             string controlFile = Path.Combine(this.ControlGitRepo.RootPath, path);
-            this.FileSystem.CreateFileWithoutClose(virtualFile);
-            this.FileSystem.CreateFileWithoutClose(controlFile);
-        }
-
-        protected void ReadFileAndWriteWithoutClose(string path, string contents)
+            IDisposable virtualHandle = this.FileSystem.CreateFileWithoutClose(virtualFile);
+            IDisposable controlHandle = this.FileSystem.CreateFileWithoutClose(controlFile);
+            return new CompositeDisposable(virtualHandle, controlHandle);
+        }
+
+        protected IDisposable ReadFileAndWriteWithoutClose(string path, string contents)
         {
             string virtualFile = Path.Combine(this.Enlistment.RepoRoot, path);
             string controlFile = Path.Combine(this.ControlGitRepo.RootPath, path);
             this.FileSystem.ReadAllText(virtualFile);
             this.FileSystem.ReadAllText(controlFile);
-            this.FileSystem.OpenFileAndWriteWithoutClose(virtualFile, contents);
-            this.FileSystem.OpenFileAndWriteWithoutClose(controlFile, contents);
+            IDisposable virtualHandle = this.FileSystem.OpenFileAndWriteWithoutClose(virtualFile, contents);
+            IDisposable controlHandle = this.FileSystem.OpenFileAndWriteWithoutClose(controlFile, contents);
+            return new CompositeDisposable(virtualHandle, controlHandle);
         }
 
         protected void CreateFolder(string folderPath)
@@ -667,5 +669,27 @@ protected void FilesShouldMatchAfterConflict()
             this.FileContentsShouldMatch("Test_ConflictTests", "ModifiedFiles", "SameChange.txt");
             this.FileContentsShouldMatch("Test_ConflictTests", "ModifiedFiles", "SuccessfulMerge.txt");
         }
+
+        /// <summary>
+        /// Disposes multiple <see cref="IDisposable"/> objects as a single unit.
+        /// Used to hold file handles open for the duration of a test scope.
+        /// </summary>
+        protected sealed class CompositeDisposable : IDisposable
+        {
+            private readonly IDisposable[] disposables;
+
+            public CompositeDisposable(params IDisposable[] disposables)
+            {
+                this.disposables = disposables;
+            }
+
+            public void Dispose()
+            {
+                foreach (IDisposable disposable in this.disposables)
+                {
+                    disposable?.Dispose();
+                }
+            }
+        }
     }
 }

GVFS/GVFS.FunctionalTests/Tests/GitCommands/StatusTests.cs

@@ -46,16 +46,20 @@ public void DeleteThenCreateThenDeleteFile()
         public void CreateFileWithoutClose()
         {
             string srcPath = @"CreateFileWithoutClose.md";
-            this.CreateFileWithoutClose(srcPath);
-            this.ValidGitStatusWithRetry(srcPath);
+            using (IDisposable handles = this.CreateFileWithoutClose(srcPath))
+            {
+                this.ValidGitStatusWithRetry(srcPath);
+            }
         }
 
         [TestCase]
         public void WriteWithoutClose()
         {
             string srcPath = @"Readme.md";
-            this.ReadFileAndWriteWithoutClose(srcPath, "More Stuff");
-            this.ValidGitStatusWithRetry(srcPath);
+            using (IDisposable handles = this.ReadFileAndWriteWithoutClose(srcPath, "More Stuff"))
+            {
+                this.ValidGitStatusWithRetry(srcPath);
+            }
         }
 
          [TestCase]