Add Directory.CreateTempSubdirectory polyfill

PolyShim.Tests/Net70/DirectoryTests.cs

@@ -36,4 +36,48 @@ public void CreateDirectory_UnixFileMode_Test()
                 Directory.Delete(tempDirPath);
         }
     }
+
+    [Fact]
+    public void CreateTempSubdirectory_Test()
+    {
+        // Act
+        var info = Directory.CreateTempSubdirectory();
+
+        try
+        {
+            // Assert
+            info.Should().NotBeNull();
+            info.Exists.Should().BeTrue();
+            info.FullName.Should()
+                .StartWith(Path.GetTempPath().TrimEnd(Path.DirectorySeparatorChar));
+        }
+        finally
+        {
+            if (Directory.Exists(info.FullName))
+                Directory.Delete(info.FullName);
+        }
+    }
+
+    [Fact]
+    public void CreateTempSubdirectory_Prefix_Test()
+    {
+        // Arrange
+        const string prefix = "polyshim-";
+
+        // Act
+        var info = Directory.CreateTempSubdirectory(prefix);
+
+        try
+        {
+            // Assert
+            info.Should().NotBeNull();
+            info.Exists.Should().BeTrue();
+            info.Name.Should().StartWith(prefix);
+        }
+        finally
+        {
+            if (Directory.Exists(info.FullName))
+                Directory.Delete(info.FullName);
+        }
+    }
 }

PolyShim/Net70/Directory.cs

@@ -46,6 +46,28 @@ public static DirectoryInfo CreateDirectory(string path, UnixFileMode unixCreate
 
             return info;
         }
+
+        // https://learn.microsoft.com/dotnet/api/system.io.directory.createtempsubdirectory#system-io-directory-createtempsubdirectory(system-string)
+        public static DirectoryInfo CreateTempSubdirectory(string? prefix = null)
+        {
+            var tempPath = Path.GetTempPath();
+
+            for (var attempt = 0; attempt < 10; attempt++)
+            {
+                var path = Path.Combine(tempPath, prefix + Path.GetRandomFileName());
+
+                try
+                {
+                    return Directory.CreateDirectory(path);
+                }
+                catch (IOException) when (Directory.Exists(path))
+                {
+                    // Collision with an existing directory, try again with a different name
+                }
+            }
+
+            throw new IOException("Failed to create a unique temporary subdirectory.");
+        }
     }
 }
 

Signatures.md

@@ -1,8 +1,8 @@
 # Signatures
 
-- **Total:** 600
+- **Total:** 601
 - **Types:** 119
-- **Members:** 481
+- **Members:** 482
 
 ___
 
@@ -155,6 +155,7 @@ ___
   - [`void Deconstruct(out object, out object?)`](https://learn.microsoft.com/dotnet/api/system.collections.dictionaryentry.deconstruct) <sup><sub>.NET Core 2.0</sub></sup>
 - `Directory`
   - [`static DirectoryInfo CreateDirectory(string, UnixFileMode)`](https://learn.microsoft.com/dotnet/api/system.io.directory.createdirectory#system-io-directory-createdirectory(system-string-system-io-unixfilemode)) <sup><sub>.NET 7.0</sub></sup>
+  - [`static DirectoryInfo CreateTempSubdirectory(string?)`](https://learn.microsoft.com/dotnet/api/system.io.directory.createtempsubdirectory#system-io-directory-createtempsubdirectory(system-string)) <sup><sub>.NET 7.0</sub></sup>
 - `DisallowNullAttribute`
   - [**[class]**](https://learn.microsoft.com/dotnet/api/system.diagnostics.codeanalysis.disallownullattribute) <sup><sub>.NET Core 3.0</sub></sup>
 - `DoesNotReturnAttribute`