Test: Changed collection of .yaml files to address pytest Deprecation…

…Warning

Details:

* The collection of .yaml files in function tests that is implemented in
  tests/functiontest/conftest.py directly created the YamlItem and YamlFile
  objects using their constructors. Pytest 6.0.0 has deprecated that
  approach and has introduced class methods 'from_parent()' for this
  purpose, and they also do support additional kwargs like the ctors do.

  This change uses the from_parent() methods in both cases if the
  method exists on the object, and uses direct creation otherwise.
  The latter was necessary because we have to pin pytest to <5.0.0 on
  py27 and py34, and to <6.0.0 on py35.

Signed-off-by: Andreas Maier <andreas.r.maier@gmx.de>

docs/changes.rst

@@ -32,6 +32,9 @@ Released: not yet
 
 * Windows install: Upgraded WinOpenSSL to 1.1.1h.
 
+* Test: Changed collection of .yaml files in function tests to address
+  DeprecationWarning issued by pytest (see issue #2430).
+
 **Enhancements:**
 
 * Removed dependency on package custom-inherit and removed package from

tests/functiontest/conftest.py

@@ -218,7 +218,13 @@ def pytest_collect_file(parent, path):
     https://docs.pytest.org/en/latest/example/nonpython.html
     """
     if path.ext == ".yaml":
-        return YamlFile(path, parent)
+        if hasattr(YamlFile, 'from_parent'):
+            # pylint: disable=no-member
+            return YamlFile.from_parent(fspath=path, parent=parent)
+        # Direct creation has been deprecated in pytest, but
+        # from_parent() was introduced only in pytest 6.0.0 and we
+        # have to pin to lower pytest versions on py27/py34/py35.
+        return YamlFile(fspath=path, parent=parent)
     return None  # to avoid pylint inconsistent-return-statements
 
 
@@ -246,7 +252,18 @@ def collect(self):
                 except KeyError:
                     raise ClientTestError("Test case #%s does not have a "
                                           "'name' attribute" % i + 1)
-                yield YamlItem(tc_name, self, testcase, filepath)
+                if hasattr(YamlItem, 'from_parent'):
+                    # pylint: disable=no-member
+                    yield YamlItem.from_parent(
+                        name=tc_name, parent=self,
+                        testcase=testcase, filepath=filepath)
+                else:
+                    # Direct creation has been deprecated in pytest, but
+                    # from_parent() was introduced only in pytest 6.0.0 and we
+                    # have to pin to lower pytest versions on py27/py34/py35.
+                    yield YamlItem(
+                        name=tc_name, parent=self,
+                        testcase=testcase, filepath=filepath)
 
 
 class YamlItem(pytest.Item):