Add convenience methods for converting a FileHandle

Add `FileHandle::into_directory` and
`FileHandle::into_regular_file`. These can be more convenient than
`FileHandle::into_type` when you know what type of file you expect.

Author: nicholasbishop

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## uefi - [Unreleased]
 
+### Added
+
+- Added `FileHandle::into_directory` and `FileHandle::into_regular_file`.
+
 ## uefi-macros - [Unreleased]
 
 ## uefi-services - [Unreleased]

src/proto/media/file/mod.rs

@@ -238,6 +238,26 @@ impl FileHandle {
             s => Err(s.into()),
         }
     }
+
+    /// If the handle represents a directory, convert it into a
+    /// [`Directory`]. Otherwise returns `None`.
+    pub fn into_directory(self) -> Option<Directory> {
+        if let Ok(FileType::Dir(dir)) = self.into_type() {
+            Some(dir)
+        } else {
+            None
+        }
+    }
+
+    /// If the handle represents a regular file, convert it into a
+    /// [`RegularFile`]. Otherwise returns `None`.
+    pub fn into_regular_file(self) -> Option<RegularFile> {
+        if let Ok(FileType::Regular(regular)) = self.into_type() {
+            Some(regular)
+        } else {
+            None
+        }
+    }
 }
 
 impl File for FileHandle {