Refactor setup.py

Removes all workarounds from setup.py in order to avoid bugs like #590

Prevents regressions by adding extra testing on Travis:
- installation from source
- installation as editable
- installation as pre-commit hook

Signed-off-by: Sorin Sbarnea <ssbarnea@redhat.com>

.gitignore

@@ -35,3 +35,4 @@ pip-log.txt
 # Coverage artifacts
 .coverage
 coverage.xml
+pip-wheel-metadata

pyproject.toml

@@ -0,0 +1,9 @@
+[build-system]
+requires = [
+  "pip>=19.1.1",
+  "setuptools >= 41.0.0",
+  "setuptools_scm >= 1.15.0",
+  "setuptools_scm_git_archive >= 1.0",
+  "wheel",
+]
+build-backend = "setuptools.build_meta"

setup.cfg

@@ -20,6 +20,7 @@ project_urls =
   Source Code = https://github.com/ansible/ansible-lint
 description = Checks playbooks for practices and behaviour that could potentially be improved
 long_description = file: README.rst
+long_description_content_type = text/x-rst
 author = Will Thames
 author_email = will@thames.id.au
 maintainer = Ansible by Red Hat

setup.py

@@ -1,147 +1,19 @@
 #! /usr/bin/env python
-"""Ansible-lint distribution package setuptools installer."""
-
 import setuptools
 
 
-try:
-    from setuptools.config import read_configuration, ConfigOptionsHandler
-    import setuptools.config
-    import setuptools.dist
-
-    # Set default value for 'use_scm_version'
-    setattr(setuptools.dist.Distribution, 'use_scm_version', False)
-
-    # Attach bool parser to 'use_scm_version' option
-    class ShimConfigOptionsHandler(ConfigOptionsHandler):
-        """Extension class for ConfigOptionsHandler."""
-
-        @property
-        def parsers(self):
-            """Return an option mapping with default data type parsers."""
-            _orig_parsers = super(ShimConfigOptionsHandler, self).parsers
-            return dict(use_scm_version=self._parse_bool, **_orig_parsers)
-
-    setuptools.config.ConfigOptionsHandler = ShimConfigOptionsHandler
-except ImportError:
-    """This is a shim for setuptools<30.3."""
-    import io
-    import json
-
-    try:
-        from configparser import ConfigParser, NoSectionError
-    except ImportError:
-        from ConfigParser import ConfigParser, NoSectionError
-        ConfigParser.read_file = ConfigParser.readfp
-
-    def maybe_read_files(d):
-        """Read files if the string starts with `file:` marker."""
-        d = d.strip()
-        if not d.startswith('file:'):
-            return d
-        descs = []
-        for fname in map(str.strip, str(d[5:]).split(',')):
-            with io.open(fname, encoding='utf-8') as f:
-                descs.append(f.read())
-        return ''.join(descs)
-
-    def cfg_val_to_list(v):
-        """Turn config val to list and filter out empty lines."""
-        return list(filter(bool, map(str.strip, str(v).strip().splitlines())))
-
-    def cfg_val_to_dict(v):
-        """Turn config val to dict and filter out empty lines."""
-        return dict(
-            map(lambda l: list(map(str.strip, l.split('=', 1))),
-                filter(bool, map(str.strip, str(v).strip().splitlines())))
-        )
-
-    def cfg_val_to_primitive(v):
-        """Parse primitive config val to appropriate data type."""
-        return json.loads(v.strip().lower())
-
-    def read_configuration(filepath):
-        """Read metadata and options from setup.cfg located at filepath."""
-        cfg = ConfigParser()
-        with io.open(filepath, encoding='utf-8') as f:
-            cfg.read_file(f)
-
-        md = dict(cfg.items('metadata'))
-        for list_key in 'classifiers', 'keywords':
-            try:
-                md[list_key] = cfg_val_to_list(md[list_key])
-            except KeyError:
-                pass
-        try:
-            md['long_description'] = maybe_read_files(md['long_description'])
-        except KeyError:
-            pass
-        opt = dict(cfg.items('options'))
-        for list_key in 'use_scm_version', 'zip_safe':
-            try:
-                opt[list_key] = cfg_val_to_primitive(opt[list_key])
-            except KeyError:
-                pass
-        for list_key in 'scripts', 'install_requires', 'setup_requires':
-            try:
-                opt[list_key] = cfg_val_to_list(opt[list_key])
-            except KeyError:
-                pass
-        try:
-            opt['package_dir'] = cfg_val_to_dict(opt['package_dir'])
-        except KeyError:
-            pass
-        try:
-            opt_package_data = dict(cfg.items('options.package_data'))
-            if not opt_package_data.get('', '').strip():
-                opt_package_data[''] = opt_package_data['*']
-                del opt_package_data['*']
-        except (KeyError, NoSectionError):
-            opt_package_data = {}
-        try:
-            opt_extras_require = dict(cfg.items('options.extras_require'))
-            opt['extras_require'] = {}
-            for k, v in opt_extras_require.items():
-                opt['extras_require'][k] = cfg_val_to_list(v)
-        except NoSectionError:
-            pass
-        opt['package_data'] = {}
-        for k, v in opt_package_data.items():
-            opt['package_data'][k] = cfg_val_to_list(v)
-        cur_pkgs = opt.get('packages', '').strip()
-        if '\n' in cur_pkgs:
-            opt['packages'] = cfg_val_to_list(opt['packages'])
-        elif cur_pkgs.startswith('find:'):
-            opt_packages_find = dict(cfg.items('options.packages.find'))
-            opt['packages'] = setuptools.find_packages(**opt_packages_find)
-        return {'metadata': md, 'options': opt}
-
-
-setup_params = {}
-declarative_setup_params = read_configuration('setup.cfg')
-
-# Patch incorrectly decoded package_dir option
-# ``egg_info`` demands native strings failing with unicode under Python 2
-# Ref https://github.com/pypa/setuptools/issues/1136
-declarative_setup_params['options']['package_dir'] = {
-    str(k): str(v)
-    for k, v in declarative_setup_params['options']['package_dir'].items()
-}
-
-setup_params = dict(setup_params, **declarative_setup_params['metadata'])
-setup_params = dict(setup_params, **declarative_setup_params['options'])
-
-
 def cut_local_version_on_upload(version):
+    """Generate a PEP440 local version if uploading to PyPI."""
     import os
     import setuptools_scm.version  # only present during setup time
-    IS_PYPI_UPLOAD = os.getenv('PYPI_UPLOAD') == 'true'
+    IS_PYPI_UPLOAD = os.getenv('PYPI_UPLOAD') == 'true'  # set in tox.ini
     return (
         '' if IS_PYPI_UPLOAD
         else setuptools_scm.version.get_local_node_and_date(version)
     )
 
 
+setup_params = {}
 setup_params['use_scm_version'] = {
     'local_scheme': cut_local_version_on_upload,
 }

tox.ini

@@ -2,6 +2,8 @@
 minversion = 3.5.3
 envlist = flake8,py{37,36,35,27}-ansible{28,27,26,devel}
 skip_missing_interpreters = True
+requires =
+  setuptools >= 41.4.0
 
 [testenv]
 deps =
@@ -35,10 +37,18 @@ usedevelop = True
 
 [testenv:metadata-validation]
 deps =
-  collective.checkdocs
-  twine
+  collective.checkdocs >= 0.2
+  path.py
+  pep517 >= 0.5.0
+  twine >= 1.13.0
 usedevelop = False
 # Ref: https://twitter.com/di_codes/status/1044358639081975813
+isolated_build = True
 commands =
-  python -m setup checkdocs check --metadata --restructuredtext --strict --verbose
-  twine check .tox/dist/*
+  python -c "import path; path.Path('{toxinidir}/dist').rmtree_p()"
+  python -m pep517.build \
+    --source \
+    --binary \
+    --out-dir {toxinidir}/dist/ \
+    {toxinidir}
+  python -m twine check {toxinidir}/dist/*