PKG: Add test extra (#27039)

Author: TomAugspurger

setup.cfg

@@ -57,6 +57,7 @@ split_penalty_after_opening_bracket = 1000000
 split_penalty_logical_operator = 30
 
 [tool:pytest]
+# sync minversion with setup.cfg & install.rst
 minversion = 4.0.2
 testpaths = pandas
 markers =

setup.py

@@ -784,4 +784,12 @@ def srcpath(name=None, suffix='.pyx', subdir='src'):
       classifiers=CLASSIFIERS,
       platforms='any',
       python_requires='>=3.5',
+      extras_require={
+          'test': [
+              # sync with setup.cfg minversion & install.rst
+              'pytest>=4.0.2',
+              'pytest-xdist',
+              'hypothesis>=3.58',
+          ]
+      },
       **setuptools_kwargs)