feat: Allow the creation of any EntryMode. (#1259)

This helps testing for one, but might also be useful in other contexts.
After all, this is a plumbing crate.

Author: Byron

gix-object/src/tree/mod.rs

@@ -12,9 +12,12 @@ pub mod write;
 /// The mode of items storable in a tree, similar to the file mode on a unix file system.
 ///
 /// Used in [`mutable::Entry`][crate::tree::Entry] and [`EntryRef`].
+///
+/// Note that even though it can be created from any `u16`, it should be preferable to
+/// create it by converting [`EntryKind`] into `EntryMode`.
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Ord, PartialOrd, Hash)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
-pub struct EntryMode(u16);
+pub struct EntryMode(pub u16);
 
 /// A discretized version of ideal and valid values for entry modes.
 ///

gix-object/tests/tree/mod.rs

@@ -220,16 +220,33 @@ mod entry_mode {
         }
 
         assert!(mode(EntryKind::Blob).is_blob());
+        assert!(EntryMode(0o100645).is_blob());
+        assert_eq!(EntryMode(0o100645).kind(), EntryKind::Blob);
+        assert!(!EntryMode(0o100675).is_executable());
+        assert!(EntryMode(0o100700).is_executable());
+        assert_eq!(EntryMode(0o100700).kind(), EntryKind::BlobExecutable);
         assert!(!mode(EntryKind::Blob).is_link());
         assert!(mode(EntryKind::BlobExecutable).is_blob());
+        assert!(mode(EntryKind::BlobExecutable).is_executable());
         assert!(mode(EntryKind::Blob).is_blob_or_symlink());
         assert!(mode(EntryKind::BlobExecutable).is_blob_or_symlink());
 
         assert!(!mode(EntryKind::Link).is_blob());
         assert!(mode(EntryKind::Link).is_link());
+        assert!(EntryMode(0o121234).is_link());
+        assert_eq!(EntryMode(0o121234).kind(), EntryKind::Link);
         assert!(mode(EntryKind::Link).is_blob_or_symlink());
         assert!(mode(EntryKind::Tree).is_tree());
+        assert!(EntryMode(0o040101).is_tree());
+        assert_eq!(EntryMode(0o040101).kind(), EntryKind::Tree);
         assert!(mode(EntryKind::Commit).is_commit());
+        assert!(EntryMode(0o167124).is_commit());
+        assert_eq!(EntryMode(0o167124).kind(), EntryKind::Commit);
+        assert_eq!(
+            EntryMode(0o000000).kind(),
+            EntryKind::Commit,
+            "commit is really 'anything else' as `kind()` can't fail"
+        );
     }
 
     #[test]