Improve Vfs interface + refactoring.

src/bsv/vfs.py

@@ -95,20 +95,39 @@ class VirtualFileSystem:
 
     def is_file(self, path: AnyBsvPath) -> bool:
         """Test if `path` is a file."""
-        path = self._make_path(path)
-        return self._real_path(path).is_file()
+        return self.metadata(path).is_file
 
     def is_dir(self, path: AnyBsvPath) -> bool:
         """Test if `path` is a directory."""
-        path = self._make_path(path)
-        return self._real_path(path).is_dir()
+        return self.metadata(path).is_dir
+
+    def is_symlink(self, path: AnyBsvPath) -> bool:
+        """Test if `path` is a symbolic link."""
+        return self.metadata(path).is_symlink
+
+    def is_other(self, path: AnyBsvPath) -> bool:
+        """Test if `path` is not a file, directory or symbolic link."""
+        return self.metadata(path).is_other
 
     def metadata(self, path: AnyBsvPath) -> FileMetadata:
         """Return the metadata of a given object."""
+        metadata = self.metadata_or_none(path)
+        if metadata is None:
+            msg = f"file '{path}' not found"
+            raise NotFoundError(msg)
+        return metadata
+
+    def metadata_or_none(self, path: AnyBsvPath) -> FileMetadata | None:
+        """Return the metadata of a given object or `None` if it does not exists."""
         path = self._make_path(path)
-        return FileMetadata.from_stat(
-            self, path, self._real_path(path).stat(follow_symlinks=False)
-        )
+        try:
+            stat = self._real_path(path).stat(follow_symlinks=False)
+        except FileNotFoundError:
+            return None
+        except OSError as err:
+            msg = f"failed to read '{path}' metadata"
+            raise FsError(msg) from err
+        return FileMetadata.from_stat(self, path, stat)
 
     def iter_dir(self, path: AnyBsvPath) -> Iterator[FileMetadata]:
         """Return the metadata of all items in the directory `path`."""
@@ -125,31 +144,18 @@ class VirtualFileSystem:
 
     def read_bytes(self, path: AnyBsvPath) -> bytes:
         """Return the content of `path` as `bytes`."""
-        path = self._make_path(path)
-        try:
-            return self._real_path(path).read_bytes()
-        except OSError as err:
-            msg = f"failed to read {path}"
-            raise FsError(msg) from err
+        with self.open_read(path) as stream:
+            return stream.read()
 
     def write_bytes(self, path: AnyBsvPath, data: Buffer | BinaryIO) -> int:
         """Create or replace a file at `path`, setting its content to `data`."""
-        path = self._make_path(path)
-        real_path = self._real_path(path)
         written = 0
-
-        try:
-            stream = real_path.open("wb")
-        except OSError as err:
-            msg = f"failed to write {path}"
-            raise FsError(msg) from err
-
-        with stream:
+        with self.open_write(path) as sout:
             if isinstance(data, Buffer):
-                written += stream.write(data)
+                written += sout.write(data)
             else:
                 while chunk := data.read(65536):
-                    written += stream.write(chunk)
+                    written += sout.write(chunk)
         return written
 
     def open_read(self, path: AnyBsvPath) -> BinaryIO:
@@ -229,12 +235,12 @@ class VirtualFileSystem:
         return self.path / path.relative_to("/")
 
 
-FileType = Literal["dir", "file", "link", "other"]
+FileType = Literal["dir", "file", "symlink", "other"]
 
-_IFMT_MAP = {
+_IFMT_MAP: dict[int, FileType] = {
     S_IFDIR: "dir",
     S_IFREG: "file",
-    S_IFLNK: "link",
+    S_IFLNK: "symlink",
 }
 
 
@@ -279,7 +285,7 @@ class FileMetadata:
         return cls(
             vfs,
             path,
-            type=cast("FileType", _IFMT_MAP.get(S_IFMT(stat.st_mode), "other")),
+            type=_IFMT_MAP.get(S_IFMT(stat.st_mode), "other"),
             permissions=Permissions(S_IMODE(stat.st_mode)),
             modification_time=datetime.fromtimestamp(stat.st_mtime, UTC),
             byte_size=stat.st_size,
@@ -295,6 +301,26 @@ class FileMetadata:
         """Return true if the file starts with a '.'."""
         return self.path.name.startswith(".")
 
+    @property
+    def is_file(self) -> bool:
+        """Test if this is a file."""
+        return self.type == "file"
+
+    @property
+    def is_dir(self) -> bool:
+        """Test if this is a directory."""
+        return self.type == "dir"
+
+    @property
+    def is_symlink(self) -> bool:
+        """Test if this is a symbolic link."""
+        return self.type == "symlink"
+
+    @property
+    def is_other(self) -> bool:
+        """Test if this is a symbolic link."""
+        return self.type == "other"
+
     def _as_tuple(
         self,
     ) -> tuple[VirtualFileSystem, PurePosixPath, FileType, Permissions, datetime, int]:

tests/test_bsv/test_vfs.py

@@ -175,20 +175,50 @@ def test_metadata(fs: VirtualFileSystem):
     assert md.path == PurePosixPath("/test_file")
     assert md.permissions == file_permissions
     assert md.type == "file"
+    assert md.is_file
+    assert not md.is_dir
+    assert not md.is_symlink
+    assert not md.is_other
     assert md.modification_time == file_time
     assert md.byte_size == len(file_content)
     assert not md.is_hidden_files
     assert fs.metadata("/test_file") == md
+    assert fs.is_file("/test_file")
+    assert not fs.is_dir("/test_file")
+    assert not fs.is_symlink("/test_file")
+    assert not fs.is_other("/test_file")
 
     fs.set_permissions("/test_file", Permissions(0o644))
     assert fs.metadata("/test_file") != md
 
     fs.mkdir("/.test_dir")
-    assert fs.metadata("/.test_dir").type == "dir"
+    md = fs.metadata("/.test_dir")
+    assert md.type == "dir"
+    assert not md.is_file
+    assert md.is_dir
+    assert not md.is_symlink
+    assert not md.is_other
     assert fs.metadata("/.test_dir").is_hidden_files
+    assert not fs.is_file("/.test_dir")
+    assert fs.is_dir("/.test_dir")
+    assert not fs.is_symlink("/.test_dir")
+    assert not fs.is_other("/.test_dir")
 
     fs.make_link("/test_link", "/link_target")
-    assert fs.metadata("/test_link").type == "link"
+    md = fs.metadata("/test_link")
+    assert md.type == "symlink"
+    assert not md.is_file
+    assert not md.is_dir
+    assert md.is_symlink
+    assert not md.is_other
+    assert not fs.is_file("/test_link")
+    assert not fs.is_dir("/test_link")
+    assert fs.is_symlink("/test_link")
+    assert not fs.is_other("/test_link")
+
+    assert fs.metadata_or_none("/does_not_exist") is None
+    with pytest.raises(FsError):
+        fs.metadata("/does_not_exist")
 
 
 ########################################################################################
@@ -199,14 +229,14 @@ def test_iter_dir(fs: VirtualFileSystem):
     expected = [
         (PurePosixPath("/dir"), "dir"),
         (PurePosixPath("/file"), "file"),
-        (PurePosixPath("/link"), "link"),
+        (PurePosixPath("/link"), "symlink"),
     ]
     for path, file_type in expected:
         if file_type == "dir":
             fs.mkdir(path)
         elif file_type == "file":
             fs.write_bytes(path, b"")
-        elif file_type == "link":
+        elif file_type == "symlink":
             fs.make_link(path, "/foobar")
 
     items_metadata = sorted(fs.iter_dir("/"))