[fix] Ignore setuptools deprecation warnings

The testing framework, some individual tests and 'buildout:develop'
call python setup.py <command> manually, which is deprecated by
setuptools. Depending on the setuptools version, suppress the
warning for now to avoid polluting the logs.

src/zc/buildout/easy_install.py

@@ -47,16 +47,20 @@ from contextlib import closing
 from setuptools.package_index import distros_for_location, URL_SCHEME
 import csv
 
+from setuptools import __version__ as setuptools_version
+setuptools_version = pkg_resources.parse_version(setuptools_version)
+
 try:
     from setuptools.wheel import Wheel  # This is the important import
-    from setuptools import __version__ as setuptools_version
     # Now we need to check if we have at least 38.2.3 for namespace support.
     SETUPTOOLS_SUPPORTS_WHEELS = (
-        pkg_resources.parse_version(setuptools_version) >=
-        pkg_resources.parse_version('38.2.3'))
+        setuptools_version >= pkg_resources.parse_version('38.2.3'))
 except ImportError:
     SETUPTOOLS_SUPPORTS_WHEELS = False
 
+SETUPTOOLS_IGNORE_WARNINGS = (
+  setuptools_version >= pkg_resources.parse_version('67.7.0'))
+
 
 BIN_SCRIPTS = 'Scripts' if WINDOWS else 'bin'
 
@@ -1229,7 +1233,11 @@ def develop(setup, dest,
         if log_level < logging.DEBUG:
             logger.debug("in: %r\n%s", directory, ' '.join(args))
 
-        call_subprocess(args)
+        if SETUPTOOLS_IGNORE_WARNINGS:
+            env = dict(os.environ, PYTHONWARNINGS='ignore')
+        else:
+            env=None
+        call_subprocess(args, env=env)
         _detect_distutils_scripts(tmp3)
         return _copyeggs(tmp3, dest, '.egg-link', undo)
 

src/zc/buildout/testing.py

@@ -166,12 +166,14 @@ def _runsetup(setup, *args):
     args = list(args)
     args.insert(0, '-q')
     here = os.getcwd()
+    ignore_warnings = zc.buildout.easy_install.SETUPTOOLS_IGNORE_WARNINGS
     try:
         os.chdir(os.path.dirname(setup))
         zc.buildout.easy_install.call_subprocess(
             [sys.executable, setup] + args,
             env=dict(os.environ,
                      PYTHONPATH=zc.buildout.easy_install.pip_pythonpath,
+                     PYTHONWARNINGS='ignore' if ignore_warnings else ''
                      ),
             )
         if os.path.exists('build'):

src/zc/buildout/tests/runsetup.txt

@@ -33,7 +33,8 @@ To illustrate this, we'll create a package in a sample buildout:
 
 We can use the buildout command to generate the hello egg:
 
-    >>> print_(system(buildout +' setup hello -q bdist_egg'), end='')
+    >>> print_(system(buildout +' setup hello -q bdist_egg',
+    ... env={'PYTHONWARNINGS':'ignore'}), end='')
     Running setup script 'hello/setup.py'.
     zip_safe flag not set; analyzing archive contents...