cacheprovider: add cache.mkdir() as a Path-returning replacement to makedir()

It is not possible to change a return type in a compatible way, so a new
method is added.

changelog/7259.feature.rst

@@ -0,0 +1,2 @@
+Added :meth:`cache.mkdir() <pytest.Cache.mkdir>`, which is similar to the existing :meth:`cache.makedir() <pytest.Cache.makedir>`,
+but returns a :class:`pathlib.Path` instead of a legacy ``py.path.local``.

src/_pytest/cacheprovider.py

@@ -60,10 +60,10 @@ class Cache:
     _cachedir = attr.ib(type=Path, repr=False)
     _config = attr.ib(type=Config, repr=False)
 
-    # sub-directory under cache-dir for directories created by "makedir"
+    # Sub-directory under cache-dir for directories created by `mkdir()`.
     _CACHE_PREFIX_DIRS = "d"
 
-    # sub-directory under cache-dir for values created by "set"
+    # Sub-directory under cache-dir for values created by `set()`.
     _CACHE_PREFIX_VALUES = "v"
 
     def __init__(
@@ -121,13 +121,15 @@ class Cache:
             stacklevel=3,
         )
 
-    def makedir(self, name: str) -> LEGACY_PATH:
+    def mkdir(self, name: str) -> Path:
         """Return a directory path object with the given name.
 
         If the directory does not yet exist, it will be created. You can use
         it to manage files to e.g. store/retrieve database dumps across test
         sessions.
 
+        .. versionadded:: 6.3
+
         :param name:
             Must be a string not containing a ``/`` separator.
             Make sure the name contains your plugin or application
@@ -138,7 +140,14 @@ class Cache:
             raise ValueError("name is not allowed to contain path separators")
         res = self._cachedir.joinpath(self._CACHE_PREFIX_DIRS, path)
         res.mkdir(exist_ok=True, parents=True)
-        return legacy_path(res)
+        return res
+
+    def makedir(self, name: str) -> LEGACY_PATH:
+        """Return a directory path object with the given name.
+
+        Same as :func:`mkdir`, but returns a legacy py path instance.
+        """
+        return legacy_path(self.mkdir(name))
 
     def _getvaluepath(self, key: str) -> Path:
         return self._cachedir.joinpath(self._CACHE_PREFIX_VALUES, Path(key))
@@ -572,8 +581,8 @@ def cacheshow(config: Config, session: Session) -> int:
         contents = sorted(ddir.rglob(glob))
         tw.sep("-", "cache directories for %r" % glob)
         for p in contents:
-            # if p.check(dir=1):
-            #    print("%s/" % p.relto(basedir))
+            # if p.is_dir():
+            #    print("%s/" % p.relative_to(basedir))
             if p.is_file():
                 key = str(p.relative_to(basedir))
                 tw.line(f"{key} is a file of length {p.stat().st_size:d}")

testing/test_cacheprovider.py

@@ -14,15 +14,15 @@ pytest_plugins = ("pytester",)
 
 
 class TestNewAPI:
-    def test_config_cache_makedir(self, pytester: Pytester) -> None:
+    def test_config_cache_mkdir(self, pytester: Pytester) -> None:
         pytester.makeini("[pytest]")
         config = pytester.parseconfigure()
         assert config.cache is not None
         with pytest.raises(ValueError):
-            config.cache.makedir("key/name")
+            config.cache.mkdir("key/name")
 
-        p = config.cache.makedir("name")
-        assert p.check()
+        p = config.cache.mkdir("name")
+        assert p.is_dir()
 
     def test_config_cache_dataerror(self, pytester: Pytester) -> None:
         pytester.makeini("[pytest]")
@@ -217,9 +217,9 @@ def test_cache_show(pytester: Pytester) -> None:
             config.cache.set("my/name", [1,2,3])
             config.cache.set("my/hello", "world")
             config.cache.set("other/some", {1:2})
-            dp = config.cache.makedir("mydb")
-            dp.ensure("hello")
-            dp.ensure("world")
+            dp = config.cache.mkdir("mydb")
+            dp.joinpath("hello").touch()
+            dp.joinpath("world").touch()
     """
     )
     result = pytester.runpytest()