use delegation to pathlib.Path to implement RelativePath class

PyTeX/build/paths/relative_path.py

@@ -1,26 +1,15 @@
-import os
-from pathlib import Path, WindowsPath, PosixPath
+from pathlib import Path
 
 from ..config import GlobalPyTeXConfig
 from PyTeX.build.enums.enums import PyTeXRootDirType
 
 
-class RelativePath(Path):
+class RelativePath:
     """
     Represents a path that knows of its corresponding root directory
     """
-    def __new__(cls, pytex_root_dir_type: PyTeXRootDirType, *args, **kwargs):
-        if cls is RelativePath:
-            cls = RelativeWindowsPath if os.name == 'nt' else RelativePosixPath
-        self = cls._from_parts(args, init=False)
-        if not self._flavour.is_supported:
-            raise NotImplementedError("cannot instantiate %r on your system"
-                                      % (cls.__name__,))
-        self._init()
-        self.__init(pytex_root_dir_type)
-        return self
-
-    def __init(self, pytex_root_dir_type: PyTeXRootDirType):
+    def __init__(self, pytex_root_dir_type: PyTeXRootDirType, *args, **kwargs):
+        self._path = Path(*args, **kwargs)
         self._pytex_root_dir_type: PyTeXRootDirType = pytex_root_dir_type
         self._root_dir: Path = {
             PyTeXRootDirType.BUILD: GlobalPyTeXConfig.build_root(),
@@ -29,6 +18,31 @@ class RelativePath(Path):
             PyTeXRootDirType.TEX_SOURCE: GlobalPyTeXConfig.tex_root()
         }[self._pytex_root_dir_type]
 
+    def __getattr__(self, attr):
+        ret = getattr(self._path, attr)
+        if isinstance(ret, Path):
+            return RelativePath(self._pytex_root_dir_type, ret)
+        else:
+            return ret
+
+    def __truediv__(self, other):
+        if isinstance(other, RelativePath):
+            path = self._path.__truediv__(other.path)
+        else:
+            path = self._path.__truediv__(other)
+        return RelativePath(self._pytex_root_dir_type, path)
+
+    def __rtruediv__(self, other):
+        if isinstance(other, RelativePath):
+            path = self._path.__rtruediv__(other.path)
+        else:
+            path = self._path.__rtruediv__(other)
+        return RelativePath(self._pytex_root_dir_type, path)
+
+    @property
+    def path(self) -> Path:
+        return self._path
+
     @property
     def root_dir_type(self) -> PyTeXRootDirType:
         return self._pytex_root_dir_type
@@ -43,11 +57,3 @@ class RelativePath(Path):
             return self.relative_to(self._root_dir)
         except ValueError as e:
             raise NotImplementedError
-
-
-class RelativeWindowsPath(RelativePath, WindowsPath):
-    pass
-
-
-class RelativePosixPath(RelativePath, PosixPath):
-    pass