From 7a709b6d30dac9409707b1b9bf50cd7022e35118 Mon Sep 17 00:00:00 2001
From: "Jason R. Coombs" <jaraco@jaraco.com>
Date: Sun, 1 Dec 2019 09:14:49 -0500
Subject: [PATCH] Restore build-backend and remove switch to avoid pep517. Ref
 #1644.

---
 pyproject.toml   | 3 ++-
 tools/tox_pip.py | 6 ------
 2 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/pyproject.toml b/pyproject.toml
index 07c23bb5f5..5a2d7d3b67 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,5 +1,6 @@
 [build-system]
-requires = ["wheel"]
+requires = ["setuptools >= 40.8", "wheel"]
+build-backend = "setuptools.build_meta"
 
 [tool.towncrier]
     package = "setuptools"
diff --git a/tools/tox_pip.py b/tools/tox_pip.py
index 5aeca80503..63518f927e 100644
--- a/tools/tox_pip.py
+++ b/tools/tox_pip.py
@@ -21,12 +21,6 @@ def pip(args):
     pypath = pypath.split(os.pathsep) if pypath is not None else []
     pypath.insert(0, TOX_PIP_DIR)
     os.environ['PYTHONPATH'] = os.pathsep.join(pypath)
-    # Disable PEP 517 support when using editable installs.
-    for n, a in enumerate(args):
-        if not a.startswith('-'):
-            if a in 'install' and '-e' in args[n:]:
-                args.insert(n + 1, '--no-use-pep517')
-            break
     # Fix call for setuptools editable install.
     for n, a in enumerate(args):
         if a == '.':