Use Black code style

.pre-commit-config.yaml

@@ -0,0 +1,6 @@
+repos:
+-   repo: https://github.com/ambv/black
+    rev: stable
+    hooks:
+    - id: black
+      language_version: python3.6

.travis.yml

@@ -14,6 +14,7 @@ install:
 script:
   - pyflakes pyhf
   - pytest -r sx --ignore tests/benchmarks/ --ignore tests/test_notebooks.py
+  - if [[ $TRAVIS_PYTHON_VERSION == '3.6' ]]; then black --check --diff --verbose .; fi
 after_success: coveralls
 
 # always test (on both 'push' and 'pr' builds in Travis)

README.md

@@ -5,6 +5,7 @@
 [![Build Status](https://travis-ci.org/diana-hep/pyhf.svg?branch=master)](https://travis-ci.org/diana-hep/pyhf)
 [![Docker Automated](https://img.shields.io/docker/automated/pyhf/pyhf.svg)](https://hub.docker.com/r/pyhf/pyhf/)
 [![Coverage Status](https://coveralls.io/repos/github/diana-hep/pyhf/badge.svg?branch=master)](https://coveralls.io/github/diana-hep/pyhf?branch=master) [![Code Health](https://landscape.io/github/diana-hep/pyhf/master/landscape.svg?style=flat)](https://landscape.io/github/diana-hep/pyhf/master)
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/ambv/black)
 
 [![Docs](https://img.shields.io/badge/docs-master-blue.svg)](https://diana-hep.github.io/pyhf)
 [![Binder](https://mybinder.org/badge.svg)](https://mybinder.org/v2/gh/diana-hep/pyhf/master?filepath=docs%2Fexamples%2Fnotebooks%2Fbinderexample%2FStatisticalAnalysis.ipynb)

binder/trigger_binder.py

@@ -8,14 +8,15 @@
 from selenium.webdriver.support.expected_conditions import staleness_of
 
 
-class SeleniumSession():
+class SeleniumSession:
     def __init__(self, args):
         self.options = Options()
         self.options.set_headless()
         self.options.add_argument('--no-sandbox')
         if args.chromedriver_path is not None:
             self.browser = webdriver.Chrome(
-                args.chromedriver_path, chrome_options=self.options)
+                args.chromedriver_path, chrome_options=self.options
+            )
         else:
             self.browser = webdriver.Chrome(chrome_options=self.options)
 
@@ -39,13 +40,23 @@ def main(args):
 
 if __name__ == '__main__':
     parser = argparse.ArgumentParser()
-    parser.add_argument('-v', '--verbose', dest='is_verbose',
-                        action='store_true',
-                        help='Print out more information')
-    parser.add_argument('--chromedriver-path', dest='chromedriver_path',
-                        type=str, default=None, help='System path to ChromeDriver')
-    parser.add_argument('--url', dest='url',
-                        type=str, default=None, help='URL for Selinium to open')
+    parser.add_argument(
+        '-v',
+        '--verbose',
+        dest='is_verbose',
+        action='store_true',
+        help='Print out more information',
+    )
+    parser.add_argument(
+        '--chromedriver-path',
+        dest='chromedriver_path',
+        type=str,
+        default=None,
+        help='System path to ChromeDriver',
+    )
+    parser.add_argument(
+        '--url', dest='url', type=str, default=None, help='URL for Selinium to open'
+    )
     args = parser.parse_args()
 
     main(args)

docs/conf.py

@@ -18,10 +18,15 @@
 #
 import os
 import sys
+
 sys.path.insert(0, os.path.abspath('..'))
 
+
 def setup(app):
-    app.add_stylesheet('https://cdnjs.cloudflare.com/ajax/libs/github-fork-ribbon-css/0.2.2/gh-fork-ribbon.min.css')
+    app.add_stylesheet(
+        'https://cdnjs.cloudflare.com/ajax/libs/github-fork-ribbon-css/0.2.2/gh-fork-ribbon.min.css'
+    )
+
 
 # -- General configuration ------------------------------------------------
 
@@ -257,29 +262,31 @@ def setup(app):
 # -- Options for LaTeX output ---------------------------------------------
 
 latex_elements = {
-     # The paper size ('letterpaper' or 'a4paper').
-     #
-     # 'papersize': 'letterpaper',
-
-     # The font size ('10pt', '11pt' or '12pt').
-     #
-     # 'pointsize': '10pt',
-
-     # Additional stuff for the LaTeX preamble.
-     #
-     # 'preamble': '',
-
-     # Latex figure (float) alignment
-     #
-     # 'figure_align': 'htbp',
+    # The paper size ('letterpaper' or 'a4paper').
+    #
+    # 'papersize': 'letterpaper',
+    # The font size ('10pt', '11pt' or '12pt').
+    #
+    # 'pointsize': '10pt',
+    # Additional stuff for the LaTeX preamble.
+    #
+    # 'preamble': '',
+    # Latex figure (float) alignment
+    #
+    # 'figure_align': 'htbp',
 }
 
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
-    (master_doc, 'pyhf.tex', u'pyhf Documentation',
-     u'Lukas Heinrich, Matthew Feickert', 'manual'),
+    (
+        master_doc,
+        'pyhf.tex',
+        u'pyhf Documentation',
+        u'Lukas Heinrich, Matthew Feickert',
+        'manual',
+    )
 ]
 
 # The name of an image file (relative to this directory) to place at the top of
@@ -319,10 +326,7 @@ def setup(app):
 
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
-man_pages = [
-    (master_doc, 'pyhf', u'pyhf Documentation',
-     [author], 1)
-]
+man_pages = [(master_doc, 'pyhf', u'pyhf Documentation', [author], 1)]
 
 # If true, show URL addresses after external links.
 #
@@ -335,9 +339,15 @@ def setup(app):
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-    (master_doc, 'pyhf', u'pyhf Documentation',
-     author, 'pyhf', 'One line description of project.',
-     'Miscellaneous'),
+    (
+        master_doc,
+        'pyhf',
+        u'pyhf Documentation',
+        author,
+        'pyhf',
+        'One line description of project.',
+        'Miscellaneous',
+    )
 ]
 
 # Documents to append as an appendix to all manuals.

docs/development.rst

@@ -4,3 +4,7 @@ Developing
 To develop, we suggest using `virtual environments <https://virtualenvwrapper.readthedocs.io/en/latest/>`__ together with ``pip`` or using `pipenv <https://pipenv.readthedocs.io/en/latest/>`__. To get all necessary packages for development::
 
     pip install --ignore-installed -U -e .[complete]
+
+Then setup the Git pre-commit hook for `Black <https://github.com/ambv/black>`__  by running::
+
+    pre-commit install

pyhf/__init__.py

@@ -1,6 +1,7 @@
 from . import tensor, optimize
 from .version import __version__
 from . import events
+
 tensorlib = tensor.numpy_backend()
 default_backend = tensorlib
 optimizer = optimize.scipy_optimizer()
@@ -49,24 +50,36 @@ def set_backend(backend, custom_optimizer=None):
     optimizer_changed = False
 
     if backend.name == 'tensorflow':
-        new_optimizer = custom_optimizer if custom_optimizer else optimize.tflow_optimizer(backend)
+        new_optimizer = (
+            custom_optimizer if custom_optimizer else optimize.tflow_optimizer(backend)
+        )
         if tensorlib.name == 'tensorflow':
             tensorlib_changed |= bool(backend.session != tensorlib.session)
     elif backend.name == 'pytorch':
-        new_optimizer = custom_optimizer if custom_optimizer else optimize.pytorch_optimizer(tensorlib=backend)
+        new_optimizer = (
+            custom_optimizer
+            if custom_optimizer
+            else optimize.pytorch_optimizer(tensorlib=backend)
+        )
     # TODO: Add support for mxnet_optimizer()
     # elif tensorlib.name == 'mxnet':
     #     new_optimizer = custom_optimizer if custom_optimizer else mxnet_optimizer()
     else:
-        new_optimizer = custom_optimizer if custom_optimizer else optimize.scipy_optimizer()
+        new_optimizer = (
+            custom_optimizer if custom_optimizer else optimize.scipy_optimizer()
+        )
 
     optimizer_changed = bool(optimizer != new_optimizer)
     # set new backend
     tensorlib = backend
     optimizer = new_optimizer
     # trigger events
-    if tensorlib_changed: events.trigger("tensorlib_changed")()
-    if optimizer_changed: events.trigger("optimizer_changed")()
+    if tensorlib_changed:
+        events.trigger("tensorlib_changed")()
+    if optimizer_changed:
+        events.trigger("optimizer_changed")()
+
 
 from .pdf import Model
+
 __all__ = ['Model', 'utils', 'modifiers', '__version__']

pyhf/commandline.py

@@ -1,6 +1,4 @@
 import logging
-logging.basicConfig()
-log = logging.getLogger(__name__)
 
 import click
 import json
@@ -14,16 +12,29 @@
 from .pdf import Model
 from .version import __version__
 
+logging.basicConfig()
+log = logging.getLogger(__name__)
+
 
 @click.group(context_settings=dict(help_option_names=['-h', '--help']))
 @click.version_option(version=__version__)
 def pyhf():
     pass
 
+
 @pyhf.command()
 @click.argument('entrypoint-xml', type=click.Path(exists=True))
-@click.option('--basedir', help='The base directory for the XML files to point relative to.', type=click.Path(exists=True), default=os.getcwd())
-@click.option('--output-file', help='The location of the output json file. If not specified, prints to screen.', default=None)
+@click.option(
+    '--basedir',
+    help='The base directory for the XML files to point relative to.',
+    type=click.Path(exists=True),
+    default=os.getcwd(),
+)
+@click.option(
+    '--output-file',
+    help='The location of the output json file. If not specified, prints to screen.',
+    default=None,
+)
 @click.option('--track-progress/--hide-progress', default=True)
 def xml2json(entrypoint_xml, basedir, output_file, track_progress):
     """ Entrypoint XML: The top-level XML file for the PDF definition. """
@@ -36,6 +47,7 @@ def xml2json(entrypoint_xml, basedir, output_file, track_progress):
         log.debug("Written to {0:s}".format(output_file))
     sys.exit(0)
 
+
 @pyhf.command()
 @click.argument('workspace', default='-')
 @click.argument('xmlfile', default='-')
@@ -45,12 +57,19 @@ def json2xml(workspace, xmlfile, specroot, dataroot):
     with click.open_file(workspace, 'r') as specstream:
         d = json.load(specstream)
         with click.open_file(xmlfile, 'w') as outstream:
-            outstream.write(writexml.writexml(d, specroot, dataroot,'').decode('utf-8'))
+            outstream.write(
+                writexml.writexml(d, specroot, dataroot, '').decode('utf-8')
+            )
     sys.exit(0)
 
+
 @pyhf.command()
 @click.argument('workspace', default='-')
-@click.option('--output-file', help='The location of the output json file. If not specified, prints to screen.', default=None)
+@click.option(
+    '--output-file',
+    help='The location of the output json file. If not specified, prints to screen.',
+    default=None,
+)
 @click.option('--measurement', default=None)
 @click.option('-p', '--patch', multiple=True)
 @click.option('--qualify-names/--no-qualify-names', default=False)
@@ -60,10 +79,14 @@ def cls(workspace, output_file, measurement, qualify_names, patch):
     measurements = d['toplvl']['measurements']
     measurement_names = [m['name'] for m in measurements]
     measurement_index = 0
-        
+
     log.debug('measurements defined:\n\t{0:s}'.format('\n\t'.join(measurement_names)))
     if measurement and measurement not in measurement_names:
-        log.error('no measurement by name \'{0:s}\' exists, pick from one of the valid ones above'.format(measurement))
+        log.error(
+            'no measurement by name \'{0:s}\' exists, pick from one of the valid ones above'.format(
+                measurement
+            )
+        )
         sys.exit(1)
     else:
         if not measurement and len(measurements) > 1:
@@ -72,16 +95,27 @@ def cls(workspace, output_file, measurement, qualify_names, patch):
         elif measurement:
             measurement_index = measurement_names.index(measurement)
 
-        log.debug('calculating CLs for measurement {0:s}'.format(measurements[measurement_index]['name']))
-        spec = {'channels':d['channels']}
+        log.debug(
+            'calculating CLs for measurement {0:s}'.format(
+                measurements[measurement_index]['name']
+            )
+        )
+        spec = {'channels': d['channels']}
         for p in patch:
             with click.open_file(p, 'r') as read_file:
                 p = jsonpatch.JsonPatch(json.loads(read_file.read()))
             spec = p.apply(spec)
-        p = Model(spec, poiname=measurements[measurement_index]['config']['poi'], qualify_names=qualify_names)
-        observed = sum((d['data'][c] for c in p.config.channels),[]) + p.config.auxdata
+        p = Model(
+            spec,
+            poiname=measurements[measurement_index]['config']['poi'],
+            qualify_names=qualify_names,
+        )
+        observed = sum((d['data'][c] for c in p.config.channels), []) + p.config.auxdata
         result = runOnePoint(1.0, observed, p)
-        result = {'CLs_obs': result[-2].tolist()[0], 'CLs_exp': result[-1].ravel().tolist()}
+        result = {
+            'CLs_obs': result[-2].tolist()[0],
+            'CLs_exp': result[-1].ravel().tolist(),
+        }
         if output_file is None:
             print(json.dumps(result, indent=4, sort_keys=True))
         else: