Allow using -p no:legacypath with pytest >= 7

The `-p no:legacypath` option for `pytest` prevents using legacy
`py.path` and forces using `pathlib` from the Python standard library
instead. 07e12f4 (Remove usage of
`py.path` with `pytest` 7) attempted to remove all uses of `py.path`
with `pytest` >= 7 so that downstream packages could use that option,
(at least with recent enough `pytest`). That commit introduced using
`getattr()` to access the `path` attribute of `_pytest.nodes.Node`
instances and falling back to the `fspath` attribute if `path` does not
exist (which happens with `pytest` < 7). However, evaluating the
`default` for `getattr()` then guarantees that `fspath` is accessed,
which is incompatible with `-p no:legacypath`. The simplest way of
avoiding accessing `fspath` is to use explicitly version-dependent code.

Author: eerovaher

pytest_mpl/plugin.py

@@ -41,6 +41,7 @@
 from urllib.request import urlopen
 
 import pytest
+from packaging.version import Version
 
 from pytest_mpl.summary.html import generate_summary_basic_html, generate_summary_html
 
@@ -56,6 +57,8 @@
   Actual shape: {actual_shape}
     {actual_path}"""
 
+PYTEST_LT_7 = Version(pytest.__version__) < Version("7.0.0")
+
 # The following are the subsets of formats supported by the Matplotlib image
 # comparison machinery
 RASTER_IMAGE_FORMATS = ['png']
@@ -64,8 +67,8 @@
 
 
 def _get_item_dir(item):
-    # .path is available starting from pytest 7, .fspath is for older versions.
-    return getattr(item, "path", Path(item.fspath)).parent
+    path = Path(item.fspath) if PYTEST_LT_7 else item.path
+    return path.parent
 
 
 def _hash_file(in_stream):