From 5f40ba47d55230719a91574eb67d3fac24f52bbf Mon Sep 17 00:00:00 2001
From: Robert Scott <code@humanleg.org.uk>
Date: Sat, 29 Aug 2020 12:55:49 +0100
Subject: [PATCH] pythonPackages.pint: add missing dependencies

importlib-metadata and packaging appear to have been falsely satisfied
by the inclusion of pytestCheckHook in checkInputs. this can be
demonstrated by attempting to build this package with doCheck = false.

also removed the isPy27 clause as package no longer seems to support <3.6
anyway now.
---
 pkgs/development/python-modules/pint/default.nix | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/pkgs/development/python-modules/pint/default.nix b/pkgs/development/python-modules/pint/default.nix
index 939eeafd9b9f..bb2a20cf62f3 100644
--- a/pkgs/development/python-modules/pint/default.nix
+++ b/pkgs/development/python-modules/pint/default.nix
@@ -1,10 +1,10 @@
 { lib
 , buildPythonPackage
 , fetchPypi
-, isPy27
 , pythonOlder
-, funcsigs
 , setuptools_scm
+, importlib-metadata
+, packaging
 # Check Inputs
 , pytestCheckHook
 , numpy
@@ -24,9 +24,10 @@ buildPythonPackage rec {
 
   disabled = pythonOlder "3.6";
 
-  propagatedBuildInputs = [
-    setuptools_scm
-  ] ++ lib.optional isPy27 funcsigs;
+  nativeBuildInputs = [ setuptools_scm ];
+  
+  propagatedBuildInputs = [ packaging ]
+    ++ lib.optionals (pythonOlder "3.8") [ importlib-metadata ];
 
   # Test suite explicitly requires pytest
   checkInputs = [