From f9ea3b242721fd071d033b8aa3fb36caaf3f764c Mon Sep 17 00:00:00 2001
From: Marius Bakke <mbakke@fastmail.com>
Date: Tue, 21 Apr 2020 13:08:41 +0200
Subject: [PATCH] gnu: python-pyrsistent: Fix build with Pytest 5.

* gnu/packages/python-xyz.scm (python-pyrsistent)[arguments]: New field.
---
 gnu/packages/python-xyz.scm | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/gnu/packages/python-xyz.scm b/gnu/packages/python-xyz.scm
index 0636b2b3ea..c5e9c8e6d7 100644
--- a/gnu/packages/python-xyz.scm
+++ b/gnu/packages/python-xyz.scm
@@ -2264,6 +2264,16 @@ from git information.
                (base32
                 "1lrsjgblnapfimd0alsi1as5nz2lfqv97131l7d6anbjzq2rjri8"))))
     (build-system python-build-system)
+    (arguments
+     '(#:phases (modify-phases %standard-phases
+                  ;; The package works fine with newer Pytest and Hypothesis, but
+                  ;; has pinned older versions to stay compatible with Python 2.
+                  (add-before 'check 'loosen-pytest-requirement
+                    (lambda _
+                      (substitute* "setup.py"
+                        (("pytest<5") "pytest")
+                        (("hypothesis<5") "hypothesis"))
+                      #t)))))
     (native-inputs
      `(("python-hypothesis" ,python-hypothesis)
        ("python-pytest" ,python-pytest)
-- 
2.20.1