fix: MockFileInfo.Exists no longer returns stale cached data (#828)

Author: siprbaum

src/System.IO.Abstractions.TestingHelpers/MockFileInfo.cs

@@ -28,6 +28,7 @@ public MockFileInfo(IMockFileDataAccessor mockFileSystem, string path) : base(mo
         /// <inheritdoc />
         public override void Delete()
         {
+            refreshOnNextRead = true;
             mockFile.Delete(path);
         }
 
@@ -221,13 +222,17 @@ public override IFileInfo CopyTo(string destFileName, bool overwrite)
         /// <inheritdoc />
         public override Stream Create()
         {
-            return mockFile.Create(FullName);
+            var result = mockFile.Create(FullName);
+            refreshOnNextRead = true;
+            return result;
         }
 
         /// <inheritdoc />
         public override StreamWriter CreateText()
         {
-            return mockFile.CreateText(FullName);
+            var result = mockFile.CreateText(FullName);
+            refreshOnNextRead = true;
+            return result;
         }
 
         /// <inheritdoc />

tests/System.IO.Abstractions.TestingHelpers.Tests/MockFileInfoTests.cs

@@ -750,6 +750,49 @@ public void MockFileInfo_Exists_ShouldUpdateCachedDataOnRefresh()
             Assert.IsTrue(fileInfo.Exists);
         }
 
+        [Test]
+        public void MockFileInfo_Create_ShouldUpdateCachedDataAndReturnTrueForExists()
+        {
+            IFileSystem fileSystem = new MockFileSystem();
+            var path = XFS.Path(@"c:\temp\file1.txt");
+            IFileInfo fileInfo = fileSystem.FileInfo.FromFileName(path);
+
+            // Act
+            fileInfo.Create().Dispose();
+
+            // Assert
+            var result = fileInfo.Exists;
+            Assert.IsTrue(result);
+        }
+
+        [Test]
+        public void MockFileInfo_CreateText_ShouldUpdateCachedDataAndReturnTrueForExists()
+        {
+            IFileSystem fileSystem = new MockFileSystem();
+            var path = XFS.Path(@"c:\temp\file1.txt");
+            IFileInfo fileInfo = fileSystem.FileInfo.FromFileName(path);
+
+            // Act
+            fileInfo.CreateText().Dispose();
+
+            // Assert
+            Assert.IsTrue(fileInfo.Exists);
+        }
+
+        [Test]
+        public void MockFileInfo_Delete_ShouldUpdateCachedDataAndReturnFalseForExists()
+        {
+            var fileSystem = new MockFileSystem();
+            var path = XFS.Path(@"c:\temp\file1.txt");
+            IFileInfo fileInfo = fileSystem.FileInfo.FromFileName(path);
+
+            // Act
+            fileInfo.Delete();
+
+            // Assert
+            Assert.IsFalse(fileInfo.Exists);
+        }
+
         [Test]
         public void MockFileInfo_Delete_ShouldThrowIfFileAccessShareHasNoWriteOrDeleteAccess()
         {