From 7c460061af140a9e19a1b1a757272851f597b38b Mon Sep 17 00:00:00 2001
From: Albert Tugushev <albert@tugushev.ru>
Date: Thu, 24 Jan 2019 11:03:30 +0300
Subject: [PATCH] Prevent to uninstall stdlib and dev packages

---
 piptools/_compat/__init__.py   | 2 ++
 piptools/_compat/pip_compat.py | 2 ++
 piptools/sync.py               | 5 ++---
 tests/test_sync.py             | 3 ++-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/piptools/_compat/__init__.py b/piptools/_compat/__init__.py
index 1fa380529..e4ac71711 100644
--- a/piptools/_compat/__init__.py
+++ b/piptools/_compat/__init__.py
@@ -29,4 +29,6 @@
     PyPI,
     install_req_from_line,
     install_req_from_editable,
+    stdlib_pkgs,
+    DEV_PKGS,
 )
diff --git a/piptools/_compat/pip_compat.py b/piptools/_compat/pip_compat.py
index 187c6ea12..82ccb8b60 100644
--- a/piptools/_compat/pip_compat.py
+++ b/piptools/_compat/pip_compat.py
@@ -36,6 +36,8 @@ def do_import(module_path, subimport=None, old_path=None):
 cmdoptions = do_import('cli.cmdoptions', old_path='cmdoptions')
 get_installed_distributions = do_import('utils.misc', 'get_installed_distributions', old_path='utils')
 PyPI = do_import('models.index', 'PyPI')
+stdlib_pkgs = do_import('utils.compat', 'stdlib_pkgs', old_path='compat')
+DEV_PKGS = do_import('commands.freeze', 'DEV_PKGS')
 
 # pip 18.1 has refactored InstallRequirement constructors use by pip-tools.
 if pkg_resources.parse_version(pip.__version__) < pkg_resources.parse_version('18.1'):
diff --git a/piptools/sync.py b/piptools/sync.py
index f4f1a23f8..619ada06d 100644
--- a/piptools/sync.py
+++ b/piptools/sync.py
@@ -4,6 +4,7 @@
 import tempfile
 from subprocess import check_call
 
+from piptools._compat import stdlib_pkgs, DEV_PKGS
 from . import click
 from .exceptions import IncompatibleRequirements, UnsupportedConstraint
 from .utils import flat_map, format_requirement, key_from_ireq, key_from_req, get_hashes_from_ireq
@@ -14,9 +15,7 @@
     'pip-tools',
     'pip-review',
     'pkg-resources',
-    'setuptools',
-    'wheel',
-]
+] + list(stdlib_pkgs) + list(DEV_PKGS)
 
 
 def dependency_tree(installed_keys, root_key):
diff --git a/tests/test_sync.py b/tests/test_sync.py
index 72b1e046e..51d7efd69 100644
--- a/tests/test_sync.py
+++ b/tests/test_sync.py
@@ -111,7 +111,8 @@ def test_diff_should_uninstall(fake_dist):
 
 def test_diff_should_not_uninstall(fake_dist):
     ignored = ('pip==7.1.0', 'pip-tools==1.1.1', 'pip-review==1.1.1',
-               'pkg-resources==0.0.0', 'setuptools==34.0.0', 'wheel==0.29.0')
+               'pkg-resources==0.0.0', 'setuptools==34.0.0', 'wheel==0.29.0',
+               'python==3.0', 'distribute==0.1', 'wsgiref==0.1', 'argparse==0.1')
     installed = [fake_dist(pkg) for pkg in ignored]
     reqs = []