Check if a path is a file or a directory: retarget net10.0, add Path.Exists, guard File.GetAttributes

- Both projects net7.0 to net10.0.
- Tests: Microsoft.NET.Test.Sdk 17.7.1 to 18.10.1, MSTest.TestAdapter and
  MSTest.TestFramework 2.2.10 replaced by the MSTest 4.4.1 meta-package,
  coverlet.collector 3.2.0 to 10.0.1. Assert.ThrowsException renamed to
  Assert.ThrowsExactly at the one call site MSTest 4 breaks.
- FileAttributesUsage: the try/catch that caught only FileNotFoundException
  becomes a Path.Exists() guard. File.GetAttributes() throws
  DirectoryNotFoundException when a parent directory is missing, which the
  old catch let through.
- File.CreateText() replaced by File.WriteAllText(path, string.Empty) in
  seven files, so the StreamWriter is no longer left open.
- FileInfoAndDirectoryInfoDrawbacks now calls Refresh() and prints the
  fresh answer after the stale one.
- New PathExistsUsage demonstration and PathTypeWithPathExistsIntegrationTest.
- Unused usings removed; three Run()-only classes made static.

Author: vladimir-pecanac-main

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
   </PropertyGroup>

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/FileAndDirectoryUsage.cs

@@ -11,7 +11,7 @@ public static void Run()
 
             // file
             var testFile = Path.Combine(Path.GetTempPath(), "test_file1.abc");
-            File.CreateText(testFile);
+            File.WriteAllText(testFile, string.Empty);
 
             isFile = File.Exists(testFile);
             isDirectory = Directory.Exists(testFile);

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/FileAttributesUsage.cs

@@ -1,6 +1,6 @@
 namespace CheckPathFileOrDirectoryCSharp
 {
-    public class FileAttributesUsage
+    public static class FileAttributesUsage
     {
         public static void Run()
         {
@@ -11,7 +11,7 @@ public static void Run()
 
             // file
             var testFile = Path.Combine(Path.GetTempPath(), "test_file4.abc");
-            File.CreateText(testFile);
+            File.WriteAllText(testFile, string.Empty);
 
             var attributes = File.GetAttributes(testFile);
 
@@ -32,18 +32,19 @@ public static void Run()
             Console.WriteLine($"{testDirectory}: isFile = {isFile}, isDirectory = {isDirectory}\n");
 
             // no file or directory
-            var notExistingPath = "someNotExistingPath4";
+            var notExistingPath = Path.Combine(Path.GetTempPath(), "someNotExistingPath4");
 
-            try
+            isDirectory = false;
+            isFile = false;
+
+            if (Path.Exists(notExistingPath))
             {
                 attributes = File.GetAttributes(notExistingPath);
+
                 isDirectory = attributes.HasFlag(FileAttributes.Directory);
                 isFile = !isDirectory;
             }
-            catch (FileNotFoundException)
-            {
-                isFile = isDirectory = false;
-            }
+
             Console.WriteLine($"{notExistingPath}: isFile = {isFile}, isDirectory = {isDirectory}\n");
         }
     }

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/FileInfoAndDirectoryInfoDrawbacks.cs

@@ -1,12 +1,6 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace CheckPathFileOrDirectoryCSharp
+namespace CheckPathFileOrDirectoryCSharp
 {
-    public class FileInfoAndDirectoryInfoDrawbacks
+    public static class FileInfoAndDirectoryInfoDrawbacks
     {
         public static void Run()
         {
@@ -23,13 +17,18 @@ public static void Run()
             Console.WriteLine($"existsFileInfo = {existsFileInfo}");
             Console.WriteLine($"existsFile = {existsFile}");
 
-            File.CreateText(testFile);
+            File.WriteAllText(testFile, string.Empty);
 
             existsFileInfo = fileInfo.Exists;
             existsFile = File.Exists(testFile);
 
             Console.WriteLine($"existsFileInfo = {existsFileInfo}");
-            Console.WriteLine($"existsFile = {existsFile}\n");
+            Console.WriteLine($"existsFile = {existsFile}");
+
+            fileInfo.Refresh();
+            existsFileInfo = fileInfo.Exists;
+
+            Console.WriteLine($"existsFileInfo after Refresh() = {existsFileInfo}\n");
         }
 
     }

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/FileInfoAndDirectoryInfoUsage.cs

@@ -1,6 +1,6 @@
 namespace CheckPathFileOrDirectoryCSharp
 {
-    public class FileInfoAndDirectoryInfoUsage
+    public static class FileInfoAndDirectoryInfoUsage
     {
         public static void Run()
         {
@@ -14,7 +14,7 @@ public static void Run()
 
             // file
             var testFile = Path.Combine(Path.GetTempPath(), "test_file2.abc");
-            File.CreateText(testFile);
+            File.WriteAllText(testFile, string.Empty);
 
             fileInfo = new FileInfo(testFile);
             directoryInfo = new DirectoryInfo(testFile);

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/PathExistsUsage.cs

@@ -0,0 +1,43 @@
+namespace CheckPathFileOrDirectoryCSharp
+{
+    public static class PathExistsUsage
+    {
+        public static void Run()
+        {
+            Console.WriteLine("Using Path.Exists:");
+
+            bool anythingHere;
+            bool isDirectory;
+            bool isFile;
+
+            // file
+            var testFile = Path.Combine(Path.GetTempPath(), "test_file5.abc");
+            File.WriteAllText(testFile, string.Empty);
+
+            anythingHere = Path.Exists(testFile);
+            isDirectory = Directory.Exists(testFile);
+            isFile = File.Exists(testFile);
+
+            Console.WriteLine($"{testFile}: anythingHere = {anythingHere}, isDirectory = {isDirectory}, isFile = {isFile}\n");
+
+            // directory
+            var testDirectory = Path.Combine(Path.GetTempPath(), "test_directory5");
+            Directory.CreateDirectory(testDirectory);
+
+            anythingHere = Path.Exists(testDirectory);
+            isDirectory = Directory.Exists(testDirectory);
+            isFile = File.Exists(testDirectory);
+
+            Console.WriteLine($"{testDirectory}: anythingHere = {anythingHere}, isDirectory = {isDirectory}, isFile = {isFile}\n");
+
+            // no file or directory
+            var notExistingPath = Path.Combine(Path.GetTempPath(), "someNotExistingPath5");
+
+            anythingHere = Path.Exists(notExistingPath);
+            isDirectory = Directory.Exists(notExistingPath);
+            isFile = File.Exists(notExistingPath);
+
+            Console.WriteLine($"{notExistingPath}: anythingHere = {anythingHere}, isDirectory = {isDirectory}, isFile = {isFile}\n");
+        }
+    }
+}

files-csharp/CheckPathFileOrDirectoryCSharp/CheckPathFileOrDirectoryCSharp/Program.cs

@@ -3,4 +3,5 @@
 FileAndDirectoryUsage.Run();
 FileInfoAndDirectoryInfoUsage.Run();
 FileInfoAndDirectoryInfoDrawbacks.Run();
+PathExistsUsage.Run();
 FileAttributesUsage.Run();

files-csharp/CheckPathFileOrDirectoryCSharp/Tests/PathTypeWithAttributesIntegrationTest.cs

@@ -17,7 +17,7 @@ public void WhenPathIsDirectory_ThenHasDirectoryAttribute()
         public void WhenPathIsFile_ThenHasNotDirectoryAttribute()
         {
             string path = Path.Combine(Path.GetTempPath(), "test_file_2.abc");
-            File.CreateText(path);
+            File.WriteAllText(path, string.Empty);
 
             var attributes = File.GetAttributes(path);
             Assert.IsFalse(attributes.HasFlag(FileAttributes.Directory));
@@ -28,7 +28,7 @@ public void WhenPathNotExists_ThenThrowsException()
         {
             string path = Path.Combine(Path.GetTempPath(), "test_not_existing_2.abc");
 
-            Assert.ThrowsException<FileNotFoundException>(() => { var attributes = File.GetAttributes(path); });
+            Assert.ThrowsExactly<FileNotFoundException>(() => { var attributes = File.GetAttributes(path); });
         }
     }
 }

files-csharp/CheckPathFileOrDirectoryCSharp/Tests/PathTypeWithFileAndDirectoryIntegrationTest.cs

@@ -17,7 +17,7 @@ public void WhenPathIsDirectory_ThenDirectoryExistsIsTrue()
         public void WhenPathIsFile_ThenFileExistsIsTrue()
         {
             string path = Path.Combine(Path.GetTempPath(), "test_file_1.abc");
-            File.CreateText(path);
+            File.WriteAllText(path, string.Empty);
 
             Assert.IsFalse(Directory.Exists(path));
             Assert.IsTrue(File.Exists(path));

files-csharp/CheckPathFileOrDirectoryCSharp/Tests/PathTypeWithFileInfoAndDirectoryInfoIntegrationTest.cs

@@ -20,7 +20,7 @@ public void WhenPathIsDirectory_ThenDirectoryExistsIsTrue()
         public void WhenPathIsFile_ThenFileExistsIsTrue()
         {
             string path = Path.Combine(Path.GetTempPath(), "test_file_3.abc");
-            File.CreateText(path);
+            File.WriteAllText(path, string.Empty);
 
             var fileInfo = new FileInfo(path);
             var directoryInfo = new DirectoryInfo(path);