Merge branch '7.x'

22 files changed, 443 insertions, 370 deletions

diff --git a/examples/aliases/aliases.py b/examples/aliases/aliases.py
index 4125c03..e7f850d 100644
--- a/examples/aliases/aliases.py
+++ b/examples/aliases/aliases.py
@@ -1,10 +1,11 @@
 import os
+
 import click
 
 try:
-    import ConfigParser as configparser
-except ImportError:
     import configparser
+except ImportError:
+    import ConfigParser as configparser
 
 
 class Config(object):
@@ -21,16 +22,16 @@ class Config(object):
         parser = configparser.RawConfigParser()
         parser.read([filename])
         try:
-            self.aliases.update(parser.items('aliases'))
+            self.aliases.update(parser.items("aliases"))
         except configparser.NoSectionError:
             pass
 
     def write_config(self, filename):
         parser = configparser.RawConfigParser()
-        parser.add_section('aliases')
+        parser.add_section("aliases")
         for key, value in self.aliases.items():
-            parser.set('aliases', key, value)
-        with open(filename, 'wb') as file:
+            parser.set("aliases", key, value)
+        with open(filename, "wb") as file:
             parser.write(file)
 
 
@@ -61,13 +62,14 @@ class AliasedGroup(click.Group):
         # allow automatic abbreviation of the command.  "status" for
         # instance will match "st".  We only allow that however if
         # there is only one command.
-        matches = [x for x in self.list_commands(ctx)
-                   if x.lower().startswith(cmd_name.lower())]
+        matches = [
+            x for x in self.list_commands(ctx) if x.lower().startswith(cmd_name.lower())
+        ]
         if not matches:
             return None
         elif len(matches) == 1:
             return click.Group.get_command(self, ctx, matches[0])
-        ctx.fail('Too many matches: %s' % ', '.join(sorted(matches)))
+        ctx.fail("Too many matches: {}".format(", ".join(sorted(matches))))
 
 
 def read_config(ctx, param, value):
@@ -78,15 +80,19 @@ def read_config(ctx, param, value):
     """
     cfg = ctx.ensure_object(Config)
     if value is None:
-        value = os.path.join(os.path.dirname(__file__), 'aliases.ini')
+        value = os.path.join(os.path.dirname(__file__), "aliases.ini")
     cfg.read_config(value)
     return value
 
 
 @click.command(cls=AliasedGroup)
-@click.option('--config', type=click.Path(exists=True, dir_okay=False),
-              callback=read_config, expose_value=False,
-              help='The config file to use instead of the default.')
+@click.option(
+    "--config",
+    type=click.Path(exists=True, dir_okay=False),
+    callback=read_config,
+    expose_value=False,
+    help="The config file to use instead of the default.",
+)
 def cli():
     """An example application that supports aliases."""
 
@@ -94,42 +100,43 @@ def cli():
 @cli.command()
 def push():
     """Pushes changes."""
-    click.echo('Push')
+    click.echo("Push")
 
 
 @cli.command()
 def pull():
     """Pulls changes."""
-    click.echo('Pull')
+    click.echo("Pull")
 
 
 @cli.command()
 def clone():
     """Clones a repository."""
-    click.echo('Clone')
+    click.echo("Clone")
 
 
 @cli.command()
 def commit():
     """Commits pending changes."""
-    click.echo('Commit')
+    click.echo("Commit")
 
 
 @cli.command()
 @pass_config
 def status(config):
     """Shows the status."""
-    click.echo('Status for %s' % config.path)
+    click.echo("Status for {}".format(config.path))
 
 
 @cli.command()
 @pass_config
-@click.argument("alias_", metavar='ALIAS', type=click.STRING)
+@click.argument("alias_", metavar="ALIAS", type=click.STRING)
 @click.argument("cmd", type=click.STRING)
-@click.option('--config_file', type=click.Path(exists=True, dir_okay=False),
-              default="aliases.ini")
+@click.option(
+    "--config_file", type=click.Path(exists=True, dir_okay=False), default="aliases.ini"
+)
 def alias(config, alias_, cmd, config_file):
     """Adds an alias to the specified configuration file."""
     config.add_alias(alias_, cmd)
     config.write_config(config_file)
-    click.echo('Added %s as alias for %s' % (alias_, cmd))
+    click.echo("Added '{}' as alias for '{}'".format(alias_, cmd))
diff --git a/examples/aliases/setup.py b/examples/aliases/setup.py
index 8d1d6a4..a3d04e7 100644
--- a/examples/aliases/setup.py
+++ b/examples/aliases/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-aliases',
-    version='1.0',
-    py_modules=['aliases'],
+    name="click-example-aliases",
+    version="1.0",
+    py_modules=["aliases"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         aliases=aliases:cli
-    ''',
+    """,
 )
diff --git a/examples/bashcompletion/bashcompletion.py b/examples/bashcompletion/bashcompletion.py
index 1072840..0502dbc 100644
--- a/examples/bashcompletion/bashcompletion.py
+++ b/examples/bashcompletion/bashcompletion.py
@@ -1,6 +1,7 @@
-import click
 import os
 
+import click
+
 
 @click.group()
 def cli():
@@ -14,14 +15,14 @@ def get_env_vars(ctx, args, incomplete):
             yield key
 
 
-@cli.command(help='A command to print environment variables')
+@cli.command(help="A command to print environment variables")
 @click.argument("envvar", type=click.STRING, autocompletion=get_env_vars)
 def cmd1(envvar):
-    click.echo('Environment variable: %s' % envvar)
-    click.echo('Value: %s' % os.environ[envvar])
+    click.echo("Environment variable: {}".format(envvar))
+    click.echo("Value: {}".format(os.environ[envvar]))
 
 
-@click.group(help='A group that holds a subcommand')
+@click.group(help="A group that holds a subcommand")
 def group():
     pass
 
@@ -29,17 +30,16 @@ def group():
 def list_users(ctx, args, incomplete):
     # You can generate completions with descriptions by returning
     # tuples in the form (completion, description).
-    users = [('bob', 'butcher'),
-             ('alice', 'baker'),
-             ('jerry', 'candlestick maker')]
-    # Ths will allow completion matches based on matches within the description string too!
+    users = [("bob", "butcher"), ("alice", "baker"), ("jerry", "candlestick maker")]
+    # Ths will allow completion matches based on matches within the
+    # description string too!
     return [user for user in users if incomplete in user[0] or incomplete in user[1]]
 
 
-@group.command(help='Choose a user')
+@group.command(help="Choose a user")
 @click.argument("user", type=click.STRING, autocompletion=list_users)
 def subcmd(user):
-    click.echo('Chosen user is %s' % user)
+    click.echo("Chosen user is {}".format(user))
 
 
 cli.add_command(group)
diff --git a/examples/bashcompletion/setup.py b/examples/bashcompletion/setup.py
index ad20081..f9a2c29 100644
--- a/examples/bashcompletion/setup.py
+++ b/examples/bashcompletion/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-bashcompletion',
-    version='1.0',
-    py_modules=['bashcompletion'],
+    name="click-example-bashcompletion",
+    version="1.0",
+    py_modules=["bashcompletion"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         bashcompletion=bashcompletion:cli
-    ''',
+    """,
 )
diff --git a/examples/colors/colors.py b/examples/colors/colors.py
index 193b927..012538d 100644
--- a/examples/colors/colors.py
+++ b/examples/colors/colors.py
@@ -1,10 +1,24 @@
 import click
 
 
-all_colors = 'black', 'red', 'green', 'yellow', 'blue', 'magenta', \
-             'cyan', 'white', 'bright_black', 'bright_red', \
-             'bright_green', 'bright_yellow', 'bright_blue', \
-             'bright_magenta', 'bright_cyan', 'bright_white'
+all_colors = (
+    "black",
+    "red",
+    "green",
+    "yellow",
+    "blue",
+    "magenta",
+    "cyan",
+    "white",
+    "bright_black",
+    "bright_red",
+    "bright_green",
+    "bright_yellow",
+    "bright_blue",
+    "bright_magenta",
+    "bright_cyan",
+    "bright_white",
+)
 
 
 @click.command()
@@ -16,13 +30,15 @@ def cli():
     Give it a try!
     """
     for color in all_colors:
-        click.echo(click.style('I am colored %s' % color, fg=color))
+        click.echo(click.style("I am colored {}".format(color), fg=color))
     for color in all_colors:
-        click.echo(click.style('I am colored %s and bold' % color,
-                               fg=color, bold=True))
+        click.echo(
+            click.style("I am colored {} and bold".format(color), fg=color, bold=True)
+        )
     for color in all_colors:
-        click.echo(click.style('I am reverse colored %s' % color, fg=color,
-                               reverse=True))
+        click.echo(
+            click.style("I am reverse colored {}".format(color), fg=color, reverse=True)
+        )
 
-    click.echo(click.style('I am blinking', blink=True))
-    click.echo(click.style('I am underlined', underline=True))
+    click.echo(click.style("I am blinking", blink=True))
+    click.echo(click.style("I am underlined", underline=True))
diff --git a/examples/colors/setup.py b/examples/colors/setup.py
index 3f8e105..6d892dd 100644
--- a/examples/colors/setup.py
+++ b/examples/colors/setup.py
@@ -1,17 +1,17 @@
 from setuptools import setup
 
 setup(
-    name='click-example-colors',
-    version='1.0',
-    py_modules=['colors'],
+    name="click-example-colors",
+    version="1.0",
+    py_modules=["colors"],
     include_package_data=True,
     install_requires=[
-        'click',
+        "click",
         # Colorama is only required for Windows.
-        'colorama',
+        "colorama",
     ],
-    entry_points='''
+    entry_points="""
         [console_scripts]
         colors=colors:cli
-    ''',
+    """,
 )
diff --git a/examples/complex/complex/cli.py b/examples/complex/complex/cli.py
index 0d10c62..c539fe8 100644
--- a/examples/complex/complex/cli.py
+++ b/examples/complex/complex/cli.py
@@ -1,13 +1,13 @@
 import os
 import sys
+
 import click
 
 
-CONTEXT_SETTINGS = dict(auto_envvar_prefix='COMPLEX')
+CONTEXT_SETTINGS = dict(auto_envvar_prefix="COMPLEX")
 
 
 class Environment(object):
-
     def __init__(self):
         self.verbose = False
         self.home = os.getcwd()
@@ -25,17 +25,14 @@ class Environment(object):
 
 
 pass_environment = click.make_pass_decorator(Environment, ensure=True)
-cmd_folder = os.path.abspath(os.path.join(os.path.dirname(__file__),
-                                          'commands'))
+cmd_folder = os.path.abspath(os.path.join(os.path.dirname(__file__), "commands"))
 
 
 class ComplexCLI(click.MultiCommand):
-
     def list_commands(self, ctx):
         rv = []
         for filename in os.listdir(cmd_folder):
-            if filename.endswith('.py') and \
-               filename.startswith('cmd_'):
+            if filename.endswith(".py") and filename.startswith("cmd_"):
                 rv.append(filename[4:-3])
         rv.sort()
         return rv
@@ -43,20 +40,22 @@ class ComplexCLI(click.MultiCommand):
     def get_command(self, ctx, name):
         try:
             if sys.version_info[0] == 2:
-                name = name.encode('ascii', 'replace')
-            mod = __import__('complex.commands.cmd_' + name,
-                             None, None, ['cli'])
+                name = name.encode("ascii", "replace")
+            mod = __import__(
+                "complex.commands.cmd_{}".format(name), None, None, ["cli"]
+            )
         except ImportError:
             return
         return mod.cli
 
 
 @click.command(cls=ComplexCLI, context_settings=CONTEXT_SETTINGS)
-@click.option('--home', type=click.Path(exists=True, file_okay=False,
-                                        resolve_path=True),
-              help='Changes the folder to operate on.')
-@click.option('-v', '--verbose', is_flag=True,
-              help='Enables verbose mode.')
+@click.option(
+    "--home",
+    type=click.Path(exists=True, file_okay=False, resolve_path=True),
+    help="Changes the folder to operate on.",
+)
+@click.option("-v", "--verbose", is_flag=True, help="Enables verbose mode.")
 @pass_environment
 def cli(ctx, verbose, home):
     """A complex command line interface."""
diff --git a/examples/complex/complex/commands/cmd_init.py b/examples/complex/complex/commands/cmd_init.py
index a77116b..c2cf770 100644
--- a/examples/complex/complex/commands/cmd_init.py
+++ b/examples/complex/complex/commands/cmd_init.py
@@ -1,13 +1,13 @@
-import click
 from complex.cli import pass_environment
 
+import click
+
 
-@click.command('init', short_help='Initializes a repo.')
-@click.argument('path', required=False, type=click.Path(resolve_path=True))
+@click.command("init", short_help="Initializes a repo.")
+@click.argument("path", required=False, type=click.Path(resolve_path=True))
 @pass_environment
 def cli(ctx, path):
     """Initializes a repository."""
     if path is None:
         path = ctx.home
-    ctx.log('Initialized the repository in %s',
-            click.format_filename(path))
+    ctx.log("Initialized the repository in %s", click.format_filename(path))
diff --git a/examples/complex/complex/commands/cmd_status.py b/examples/complex/complex/commands/cmd_status.py
index 12229c4..92275bb 100644
--- a/examples/complex/complex/commands/cmd_status.py
+++ b/examples/complex/complex/commands/cmd_status.py
@@ -1,10 +1,11 @@
-import click
 from complex.cli import pass_environment
 
+import click
+
 
-@click.command('status', short_help='Shows file changes.')
+@click.command("status", short_help="Shows file changes.")
 @pass_environment
 def cli(ctx):
     """Shows file changes in the current working directory."""
-    ctx.log('Changed files: none')
-    ctx.vlog('bla bla bla, debug info')
+    ctx.log("Changed files: none")
+    ctx.vlog("bla bla bla, debug info")
diff --git a/examples/complex/setup.py b/examples/complex/setup.py
index dee002c..afe9728 100644
--- a/examples/complex/setup.py
+++ b/examples/complex/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-complex',
-    version='1.0',
-    packages=['complex', 'complex.commands'],
+    name="click-example-complex",
+    version="1.0",
+    packages=["complex", "complex.commands"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         complex=complex.cli:cli
-    ''',
+    """,
 )
diff --git a/examples/imagepipe/imagepipe.py b/examples/imagepipe/imagepipe.py
index cc35dca..d46c33f 100644
--- a/examples/imagepipe/imagepipe.py
+++ b/examples/imagepipe/imagepipe.py
@@ -1,6 +1,10 @@
-import click
 from functools import update_wrapper
-from PIL import Image, ImageFilter, ImageEnhance
+
+from PIL import Image
+from PIL import ImageEnhance
+from PIL import ImageFilter
+
+import click
 
 
 @click.group(chain=True)
@@ -39,10 +43,13 @@ def processor(f):
     """Helper decorator to rewrite a function so that it returns another
     function from it.
     """
+
     def new_func(*args, **kwargs):
         def processor(stream):
             return f(stream, *args, **kwargs)
+
         return processor
+
     return update_wrapper(new_func, f)
 
 
@@ -50,12 +57,14 @@ def generator(f):
     """Similar to the :func:`processor` but passes through old values
     unchanged and does not pass through the values as parameter.
     """
+
     @processor
     def new_func(stream, *args, **kwargs):
         for item in stream:
             yield item
         for item in f(*args, **kwargs):
             yield item
+
     return update_wrapper(new_func, f)
 
 
@@ -64,9 +73,15 @@ def copy_filename(new, old):
     return new
 
 
-@cli.command('open')
-@click.option('-i', '--image', 'images', type=click.Path(),
-              multiple=True, help='The image file to open.')
+@cli.command("open")
+@click.option(
+    "-i",
+    "--image",
+    "images",
+    type=click.Path(),
+    multiple=True,
+    help="The image file to open.",
+)
 @generator
 def open_cmd(images):
     """Loads one or multiple images for processing.  The input parameter
@@ -74,47 +89,52 @@ def open_cmd(images):
     """
     for image in images:
         try:
-            click.echo('Opening "%s"' % image)
-            if image == '-':
+            click.echo("Opening '{}'".format(image))
+            if image == "-":
                 img = Image.open(click.get_binary_stdin())
-                img.filename = '-'
+                img.filename = "-"
             else:
                 img = Image.open(image)
             yield img
         except Exception as e:
-            click.echo('Could not open image "%s": %s' % (image, e), err=True)
+            click.echo("Could not open image '{}': {}".format(image, e), err=True)
 
 
-@cli.command('save')
-@click.option('--filename', default='processed-%04d.png', type=click.Path(),
-              help='The format for the filename.',
-              show_default=True)
+@cli.command("save")
+@click.option(
+    "--filename",
+    default="processed-{:04}.png",
+    type=click.Path(),
+    help="The format for the filename.",
+    show_default=True,
+)
 @processor
 def save_cmd(images, filename):
     """Saves all processed images to a series of files."""
     for idx, image in enumerate(images):
         try:
-            fn = filename % (idx + 1)
-            click.echo('Saving "%s" as "%s"' % (image.filename, fn))
+            fn = filename.format(idx + 1)
+            click.echo("Saving '{}' as '{}'".format(image.filename, fn))
             yield image.save(fn)
         except Exception as e:
-            click.echo('Could not save image "%s": %s' %
-                       (image.filename, e), err=True)
+            click.echo(
+                "Could not save image '{}': {}".format(image.filename, e), err=True
+            )
 
 
-@cli.command('display')
+@cli.command("display")
 @processor
 def display_cmd(images):
     """Opens all images in an image viewer."""
     for image in images:
-        click.echo('Displaying "%s"' % image.filename)
+        click.echo("Displaying '{}'".format(image.filename))
         image.show()
         yield image
 
 
-@cli.command('resize')
-@click.option('-w', '--width', type=int, help='The new width of the image.')
-@click.option('-h', '--height', type=int, help='The new height of the image.')
+@cli.command("resize")
+@click.option("-w", "--width", type=int, help="The new width of the image.")
+@click.option("-h", "--height", type=int, help="The new height of the image.")
 @processor
 def resize_cmd(images, width, height):
     """Resizes an image by fitting it into the box without changing
@@ -122,14 +142,15 @@ def resize_cmd(images, width, height):
     """
     for image in images:
         w, h = (width or image.size[0], height or image.size[1])
-        click.echo('Resizing "%s" to %dx%d' % (image.filename, w, h))
+        click.echo("Resizing '{}' to {}x{}".format(image.filename, w, h))
         image.thumbnail((w, h))
         yield image
 
 
-@cli.command('crop')
-@click.option('-b', '--border', type=int, help='Crop the image from all '
-              'sides by this amount.')
+@cli.command("crop")
+@click.option(
+    "-b", "--border", type=int, help="Crop the image from all sides by this amount."
+)
 @processor
 def crop_cmd(images, border):
     """Crops an image from all edges."""
@@ -139,7 +160,7 @@ def crop_cmd(images, border):
         if border is not None:
             for idx, val in enumerate(box):
                 box[idx] = max(0, val - border)
-            click.echo('Cropping "%s" by %dpx' % (image.filename, border))
+            click.echo("Cropping '{}' by {}px".format(image.filename, border))
             yield copy_filename(image.crop(box), image)
         else:
             yield image
@@ -149,96 +170,104 @@ def convert_rotation(ctx, param, value):
     if value is None:
         return
     value = value.lower()
-    if value in ('90', 'r', 'right'):
+    if value in ("90", "r", "right"):
         return (Image.ROTATE_90, 90)
-    if value in ('180', '-180'):
+    if value in ("180", "-180"):
         return (Image.ROTATE_180, 180)
-    if value in ('-90', '270', 'l', 'left'):
+    if value in ("-90", "270", "l", "left"):
         return (Image.ROTATE_270, 270)
-    raise click.BadParameter('invalid rotation "%s"' % value)
+    raise click.BadParameter("invalid rotation '{}'".format(value))
 
 
 def convert_flip(ctx, param, value):
     if value is None:
         return
     value = value.lower()
-    if value in ('lr', 'leftright'):
-        return (Image.FLIP_LEFT_RIGHT, 'left to right')
-    if value in ('tb', 'topbottom', 'upsidedown', 'ud'):
-        return (Image.FLIP_LEFT_RIGHT, 'top to bottom')
-    raise click.BadParameter('invalid flip "%s"' % value)
-
-
-@cli.command('transpose')
-@click.option('-r', '--rotate', callback=convert_rotation,
-              help='Rotates the image (in degrees)')
-@click.option('-f', '--flip', callback=convert_flip,
-              help='Flips the image  [LR / TB]')
+    if value in ("lr", "leftright"):
+        return (Image.FLIP_LEFT_RIGHT, "left to right")
+    if value in ("tb", "topbottom", "upsidedown", "ud"):
+        return (Image.FLIP_LEFT_RIGHT, "top to bottom")
+    raise click.BadParameter("invalid flip '{}'".format(value))
+
+
+@cli.command("transpose")
+@click.option(
+    "-r", "--rotate", callback=convert_rotation, help="Rotates the image (in degrees)"
+)
+@click.option("-f", "--flip", callback=convert_flip, help="Flips the image  [LR / TB]")
 @processor
 def transpose_cmd(images, rotate, flip):
     """Transposes an image by either rotating or flipping it."""
     for image in images:
         if rotate is not None:
             mode, degrees = rotate
-            click.echo('Rotate "%s" by %ddeg' % (image.filename, degrees))
+            click.echo("Rotate '{}' by {}deg".format(image.filename, degrees))
             image = copy_filename(image.transpose(mode), image)
         if flip is not None:
             mode, direction = flip
-            click.echo('Flip "%s" %s' % (image.filename, direction))
+            click.echo("Flip '{}' {}".format(image.filename, direction))
             image = copy_filename(image.transpose(mode), image)
         yield image
 
 
-@cli.command('blur')
-@click.option('-r', '--radius', default=2, show_default=True,
-              help='The blur radius.')
+@cli.command("blur")
+@click.option("-r", "--radius", default=2, show_default=True, help="The blur radius.")
 @processor
 def blur_cmd(images, radius):
     """Applies gaussian blur."""
     blur = ImageFilter.GaussianBlur(radius)
     for image in images:
-        click.echo('Blurring "%s" by %dpx' % (image.filename, radius))
+        click.echo("Blurring '{}' by {}px".format(image.filename, radius))
         yield copy_filename(image.filter(blur), image)
 
 
-@cli.command('smoothen')
-@click.option('-i', '--iterations', default=1, show_default=True,
-              help='How many iterations of the smoothen filter to run.')
+@cli.command("smoothen")
+@click.option(
+    "-i",
+    "--iterations",
+    default=1,
+    show_default=True,
+    help="How many iterations of the smoothen filter to run.",
+)
 @processor
 def smoothen_cmd(images, iterations):
     """Applies a smoothening filter."""
     for image in images:
-        click.echo('Smoothening "%s" %d time%s' %
-                   (image.filename, iterations, iterations != 1 and 's' or '',))
-        for x in range(iterations):
+        click.echo(
+            "Smoothening '{}' {} time{}".format(
+                image.filename, iterations, "s" if iterations != 1 else ""
+            )
+        )
+        for _ in range(iterations):
             image = copy_filename(image.filter(ImageFilter.BLUR), image)
         yield image
 
 
-@cli.command('emboss')
+@cli.command("emboss")
 @processor
 def emboss_cmd(images):
     """Embosses an image."""
     for image in images:
-        click.echo('Embossing "%s"' % image.filename)
+        click.echo("Embossing '{}'".format(image.filename))
         yield copy_filename(image.filter(ImageFilter.EMBOSS), image)
 
 
-@cli.command('sharpen')
-@click.option('-f', '--factor', default=2.0,
-              help='Sharpens the image.', show_default=True)
+@cli.command("sharpen")
+@click.option(
+    "-f", "--factor", default=2.0, help="Sharpens the image.", show_default=True
+)
 @processor
 def sharpen_cmd(images, factor):
     """Sharpens an image."""
     for image in images:
-        click.echo('Sharpen "%s" by %f' % (image.filename, factor))
+        click.echo("Sharpen '{}' by {}".format(image.filename, factor))
         enhancer = ImageEnhance.Sharpness(image)
         yield copy_filename(enhancer.enhance(max(1.0, factor)), image)
 
 
-@cli.command('paste')
-@click.option('-l', '--left', default=0, help='Offset from left.')
-@click.option('-r', '--right', default=0, help='Offset from right.')
+@cli.command("paste")
+@click.option("-l", "--left", default=0, help="Offset from left.")
+@click.option("-r", "--right", default=0, help="Offset from right.")
 @processor
 def paste_cmd(images, left, right):
     """Pastes the second image on the first image and leaves the rest
@@ -253,13 +282,12 @@ def paste_cmd(images, left, right):
             yield image
         return
 
-    click.echo('Paste "%s" on "%s"' %
-               (to_paste.filename, image.filename))
+    click.echo("Paste '{}' on '{}'".format(to_paste.filename, image.filename))
     mask = None
-    if to_paste.mode == 'RGBA' or 'transparency' in to_paste.info:
+    if to_paste.mode == "RGBA" or "transparency" in to_paste.info:
         mask = to_paste
     image.paste(to_paste, (left, right), mask)
-    image.filename += '+' + to_paste.filename
+    image.filename += "+{}".format(to_paste.filename)
     yield image
 
     for image in imageiter:
diff --git a/examples/imagepipe/setup.py b/examples/imagepipe/setup.py
index d2d8d99..c42b5ff 100644
--- a/examples/imagepipe/setup.py
+++ b/examples/imagepipe/setup.py
@@ -1,16 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-imagepipe',
-    version='1.0',
-    py_modules=['imagepipe'],
+    name="click-example-imagepipe",
+    version="1.0",
+    py_modules=["imagepipe"],
     include_package_data=True,
-    install_requires=[
-        'click',
-        'pillow',
-    ],
-    entry_points='''
+    install_requires=["click", "pillow"],
+    entry_points="""
         [console_scripts]
         imagepipe=imagepipe:cli
-    ''',
+    """,
 )
diff --git a/examples/inout/inout.py b/examples/inout/inout.py
index b93f306..854c84e 100644
--- a/examples/inout/inout.py
+++ b/examples/inout/inout.py
@@ -2,8 +2,8 @@ import click
 
 
 @click.command()
-@click.argument('input', type=click.File('rb'), nargs=-1)
-@click.argument('output', type=click.File('wb'))
+@click.argument("input", type=click.File("rb"), nargs=-1)
+@click.argument("output", type=click.File("wb"))
 def cli(input, output):
     """This script works similar to the Unix `cat` command but it writes
     into a specific file (which could be the standard output as denoted by
diff --git a/examples/inout/setup.py b/examples/inout/setup.py
index 5c61364..ff673e3 100644
--- a/examples/inout/setup.py
+++ b/examples/inout/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-inout',
-    version='0.1',
-    py_modules=['inout'],
+    name="click-example-inout",
+    version="0.1",
+    py_modules=["inout"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         inout=inout:cli
-    ''',
+    """,
 )
diff --git a/examples/naval/naval.py b/examples/naval/naval.py
index 2d173d8..b8d31e1 100644
--- a/examples/naval/naval.py
+++ b/examples/naval/naval.py
@@ -17,54 +17,56 @@ def ship():
     """Manages ships."""
 
 
-@ship.command('new')
-@click.argument('name')
+@ship.command("new")
+@click.argument("name")
 def ship_new(name):
     """Creates a new ship."""
-    click.echo('Created ship %s' % name)
+    click.echo("Created ship {}".format(name))
 
 
-@ship.command('move')
-@click.argument('ship')
-@click.argument('x', type=float)
-@click.argument('y', type=float)
-@click.option('--speed', metavar='KN', default=10,
-              help='Speed in knots.')
+@ship.command("move")
+@click.argument("ship")
+@click.argument("x", type=float)
+@click.argument("y", type=float)
+@click.option("--speed", metavar="KN", default=10, help="Speed in knots.")
 def ship_move(ship, x, y, speed):
     """Moves SHIP to the new location X,Y."""
-    click.echo('Moving ship %s to %s,%s with speed %s' % (ship, x, y, speed))
+    click.echo("Moving ship {} to {},{} with speed {}".format(ship, x, y, speed))
 
 
-@ship.command('shoot')
-@click.argument('ship')
-@click.argument('x', type=float)
-@click.argument('y', type=float)
+@ship.command("shoot")
+@click.argument("ship")
+@click.argument("x", type=float)
+@click.argument("y", type=float)
 def ship_shoot(ship, x, y):
     """Makes SHIP fire to X,Y."""
-    click.echo('Ship %s fires to %s,%s' % (ship, x, y))
+    click.echo("Ship {} fires to {},{}".format(ship, x, y))
 
 
-@cli.group('mine')
+@cli.group("mine")
 def mine():
     """Manages mines."""
 
 
-@mine.command('set')
-@click.argument('x', type=float)
-@click.argument('y', type=float)
-@click.option('ty', '--moored', flag_value='moored',
-              default=True,
-              help='Moored (anchored) mine. Default.')
-@click.option('ty', '--drifting', flag_value='drifting',
-              help='Drifting mine.')
+@mine.command("set")
+@click.argument("x", type=float)
+@click.argument("y", type=float)
+@click.option(
+    "ty",
+    "--moored",
+    flag_value="moored",
+    default=True,
+    help="Moored (anchored) mine. Default.",
+)
+@click.option("ty", "--drifting", flag_value="drifting", help="Drifting mine.")
 def mine_set(x, y, ty):
     """Sets a mine at a specific coordinate."""
-    click.echo('Set %s mine at %s,%s' % (ty, x, y))
+    click.echo("Set {} mine at {},{}".format(ty, x, y))
 
 
-@mine.command('remove')
-@click.argument('x', type=float)
-@click.argument('y', type=float)
+@mine.command("remove")
+@click.argument("x", type=float)
+@click.argument("y", type=float)
 def mine_remove(x, y):
     """Removes a mine at a specific coordinate."""
-    click.echo('Removed mine at %s,%s' % (x, y))
+    click.echo("Removed mine at {},{}".format(x, y))
diff --git a/examples/naval/setup.py b/examples/naval/setup.py
index 124addf..37b39f5 100644
--- a/examples/naval/setup.py
+++ b/examples/naval/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-naval',
-    version='2.0',
-    py_modules=['naval'],
+    name="click-example-naval",
+    version="2.0",
+    py_modules=["naval"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         naval=naval:cli
-    ''',
+    """,
 )
diff --git a/examples/repo/repo.py b/examples/repo/repo.py
index 2b1992d..5fd6ead 100644
--- a/examples/repo/repo.py
+++ b/examples/repo/repo.py
@@ -1,12 +1,11 @@
 import os
-import sys
 import posixpath
+import sys
 
 import click
 
 
 class Repo(object):
-
     def __init__(self, home):
         self.home = home
         self.config = {}
@@ -15,23 +14,32 @@ class Repo(object):
     def set_config(self, key, value):
         self.config[key] = value
         if self.verbose:
-            click.echo('  config[%s] = %s' % (key, value), file=sys.stderr)
+            click.echo("  config[{}] = {}".format(key, value), file=sys.stderr)
 
     def __repr__(self):
-        return '<Repo %r>' % self.home
+        return "<Repo {}>".format(self.home)
 
 
 pass_repo = click.make_pass_decorator(Repo)
 
 
 @click.group()
-@click.option('--repo-home', envvar='REPO_HOME', default='.repo',
-              metavar='PATH', help='Changes the repository folder location.')
-@click.option('--config', nargs=2, multiple=True,
-              metavar='KEY VALUE', help='Overrides a config key/value pair.')
-@click.option('--verbose', '-v', is_flag=True,
-              help='Enables verbose mode.')
-@click.version_option('1.0')
+@click.option(
+    "--repo-home",
+    envvar="REPO_HOME",
+    default=".repo",
+    metavar="PATH",
+    help="Changes the repository folder location.",
+)
+@click.option(
+    "--config",
+    nargs=2,
+    multiple=True,
+    metavar="KEY VALUE",
+    help="Overrides a config key/value pair.",
+)
+@click.option("--verbose", "-v", is_flag=True, help="Enables verbose mode.")
+@click.version_option("1.0")
 @click.pass_context
 def cli(ctx, repo_home, config, verbose):
     """Repo is a command line tool that showcases how to build complex
@@ -50,12 +58,16 @@ def cli(ctx, repo_home, config, verbose):
 
 
 @cli.command()
-@click.argument('src')
-@click.argument('dest', required=False)
-@click.option('--shallow/--deep', default=False,
-              help='Makes a checkout shallow or deep.  Deep by default.')
-@click.option('--rev', '-r', default='HEAD',
-              help='Clone a specific revision instead of HEAD.')
+@click.argument("src")
+@click.argument("dest", required=False)
+@click.option(
+    "--shallow/--deep",
+    default=False,
+    help="Makes a checkout shallow or deep.  Deep by default.",
+)
+@click.option(
+    "--rev", "-r", default="HEAD", help="Clone a specific revision instead of HEAD."
+)
 @pass_repo
 def clone(repo, src, dest, shallow, rev):
     """Clones a repository.
@@ -65,12 +77,12 @@ def clone(repo, src, dest, shallow, rev):
     of SRC and create that folder.
     """
     if dest is None:
-        dest = posixpath.split(src)[-1] or '.'
-    click.echo('Cloning repo %s to %s' % (src, os.path.abspath(dest)))
+        dest = posixpath.split(src)[-1] or "."
+    click.echo("Cloning repo {} to {}".format(src, os.path.abspath(dest)))
     repo.home = dest
     if shallow:
-        click.echo('Making shallow checkout')
-    click.echo('Checking out revision %s' % rev)
+        click.echo("Making shallow checkout")
+    click.echo("Checking out revision {}".format(rev))
 
 
 @cli.command()
@@ -81,33 +93,35 @@ def delete(repo):
 
     This will throw away the current repository.
     """
-    click.echo('Destroying repo %s' % repo.home)
-    click.echo('Deleted!')
+    click.echo("Destroying repo {}".format(repo.home))
+    click.echo("Deleted!")
 
 
 @cli.command()
-@click.option('--username', prompt=True,
-              help='The developer\'s shown username.')
-@click.option('--email', prompt='E-Mail',
-              help='The developer\'s email address')
-@click.password_option(help='The login password.')
+@click.option("--username", prompt=True, help="The developer's shown username.")
+@click.option("--email", prompt="E-Mail", help="The developer's email address")
+@click.password_option(help="The login password.")
 @pass_repo
 def setuser(repo, username, email, password):
     """Sets the user credentials.
 
     This will override the current user config.
     """
-    repo.set_config('username', username)
-    repo.set_config('email', email)
-    repo.set_config('password', '*' * len(password))
-    click.echo('Changed credentials.')
+    repo.set_config("username", username)
+    repo.set_config("email", email)
+    repo.set_config("password", "*" * len(password))
+    click.echo("Changed credentials.")
 
 
 @cli.command()
-@click.option('--message', '-m', multiple=True,
-              help='The commit message.  If provided multiple times each '
-              'argument gets converted into a new line.')
-@click.argument('files', nargs=-1, type=click.Path())
+@click.option(
+    "--message",
+    "-m",
+    multiple=True,
+    help="The commit message.  If provided multiple times each"
+    " argument gets converted into a new line.",
+)
+@click.argument("files", nargs=-1, type=click.Path())
 @pass_repo
 def commit(repo, files, message):
     """Commits outstanding changes.
@@ -119,33 +133,34 @@ def commit(repo, files, message):
     will be committed.
     """
     if not message:
-        marker = '# Files to be committed:'
-        hint = ['', '', marker, '#']
+        marker = "# Files to be committed:"
+        hint = ["", "", marker, "#"]
         for file in files:
-            hint.append('#   U %s' % file)
-        message = click.edit('\n'.join(hint))
+            hint.append("#   U {}".format(file))
+        message = click.edit("\n".join(hint))
         if message is None:
-            click.echo('Aborted!')
+            click.echo("Aborted!")
             return
         msg = message.split(marker)[0].rstrip()
         if not msg:
-            click.echo('Aborted! Empty commit message')
+            click.echo("Aborted! Empty commit message")
             return
     else:
-        msg = '\n'.join(message)
-    click.echo('Files to be committed: %s' % (files,))
-    click.echo('Commit message:\n' + msg)
+        msg = "\n".join(message)
+    click.echo("Files to be committed: {}".format(files))
+    click.echo("Commit message:\n{}".format(msg))
 
 
-@cli.command(short_help='Copies files.')
-@click.option('--force', is_flag=True,
-              help='forcibly copy over an existing managed file')
-@click.argument('src', nargs=-1, type=click.Path())
-@click.argument('dst', type=click.Path())
+@cli.command(short_help="Copies files.")
+@click.option(
+    "--force", is_flag=True, help="forcibly copy over an existing managed file"
+)
+@click.argument("src", nargs=-1, type=click.Path())
+@click.argument("dst", type=click.Path())
 @pass_repo
 def copy(repo, src, dst, force):
     """Copies one or multiple files to a new location.  This copies all
     files from SRC to DST.
     """
     for fn in src:
-        click.echo('Copy from %s -> %s' % (fn, dst))
+        click.echo("Copy from {} -> {}".format(fn, dst))
diff --git a/examples/repo/setup.py b/examples/repo/setup.py
index 19aab70..3028020 100644
--- a/examples/repo/setup.py
+++ b/examples/repo/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-repo',
-    version='0.1',
-    py_modules=['repo'],
+    name="click-example-repo",
+    version="0.1",
+    py_modules=["repo"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         repo=repo:cli
-    ''',
+    """,
 )
diff --git a/examples/termui/setup.py b/examples/termui/setup.py
index 14558e8..7791bae 100644
--- a/examples/termui/setup.py
+++ b/examples/termui/setup.py
@@ -1,17 +1,17 @@
 from setuptools import setup
 
 setup(
-    name='click-example-termui',
-    version='1.0',
-    py_modules=['termui'],
+    name="click-example-termui",
+    version="1.0",
+    py_modules=["termui"],
     include_package_data=True,
     install_requires=[
-        'click',
+        "click",
         # Colorama is only required for Windows.
-        'colorama',
+        "colorama",
     ],
-    entry_points='''
+    entry_points="""
         [console_scripts]
         termui=termui:cli
-    ''',
+    """,
 )
diff --git a/examples/termui/termui.py b/examples/termui/termui.py
index 793afa4..7b3da43 100644
--- a/examples/termui/termui.py
+++ b/examples/termui/termui.py
@@ -1,13 +1,9 @@
 # coding: utf-8
-import click
 import math
-import time
 import random
+import time
 
-try:
-    range_type = xrange
-except NameError:
-    range_type = range
+import click
 
 
 @click.group()
@@ -19,26 +15,30 @@ def cli():
 @cli.command()
 def colordemo():
     """Demonstrates ANSI color support."""
-    for color in 'red', 'green', 'blue':
-        click.echo(click.style('I am colored %s' % color, fg=color))
-        click.echo(click.style('I am background colored %s' % color, bg=color))
+    for color in "red", "green", "blue":
+        click.echo(click.style("I am colored {}".format(color), fg=color))
+        click.echo(click.style("I am background colored {}".format(color), bg=color))
 
 
 @cli.command()
 def pager():
     """Demonstrates using the pager."""
     lines = []
-    for x in range_type(200):
-        lines.append('%s. Hello World!' % click.style(str(x), fg='green'))
-    click.echo_via_pager('\n'.join(lines))
+    for x in range(200):
+        lines.append("{}. Hello World!".format(click.style(str(x), fg="green")))
+    click.echo_via_pager("\n".join(lines))
 
 
 @cli.command()
-@click.option('--count', default=8000, type=click.IntRange(1, 100000),
-              help='The number of items to process.')
+@click.option(
+    "--count",
+    default=8000,
+    type=click.IntRange(1, 100000),
+    help="The number of items to process.",
+)
 def progress(count):
     """Demonstrates the progress bar."""
-    items = range_type(count)
+    items = range(count)
 
     def process_slowly(item):
         time.sleep(0.002 * random.random())
@@ -48,54 +48,68 @@ def progress(count):
             if random.random() > 0.3:
                 yield item
 
-    with click.progressbar(items, label='Processing accounts',
-                           fill_char=click.style('#', fg='green')) as bar:
+    with click.progressbar(
+        items, label="Processing accounts", fill_char=click.style("#", fg="green")
+    ) as bar:
         for item in bar:
             process_slowly(item)
 
     def show_item(item):
         if item is not None:
-            return 'Item #%d' % item
-
-    with click.progressbar(filter(items), label='Committing transaction',
-                           fill_char=click.style('#', fg='yellow'),
-                           item_show_func=show_item) as bar:
+            return "Item #{}".format(item)
+
+    with click.progressbar(
+        filter(items),
+        label="Committing transaction",
+        fill_char=click.style("#", fg="yellow"),
+        item_show_func=show_item,
+    ) as bar:
         for item in bar:
             process_slowly(item)
 
-    with click.progressbar(length=count, label='Counting',
-                           bar_template='%(label)s  %(bar)s | %(info)s',
-                           fill_char=click.style(u'█', fg='cyan'),
-                           empty_char=' ') as bar:
+    with click.progressbar(
+        length=count,
+        label="Counting",
+        bar_template="%(label)s  %(bar)s | %(info)s",
+        fill_char=click.style(u"█", fg="cyan"),
+        empty_char=" ",
+    ) as bar:
         for item in bar:
             process_slowly(item)
 
-    with click.progressbar(length=count, width=0, show_percent=False,
-                           show_eta=False,
-                           fill_char=click.style('#', fg='magenta')) as bar:
+    with click.progressbar(
+        length=count,
+        width=0,
+        show_percent=False,
+        show_eta=False,
+        fill_char=click.style("#", fg="magenta"),
+    ) as bar:
         for item in bar:
             process_slowly(item)
 
     # 'Non-linear progress bar'
-    steps = [math.exp( x * 1. / 20) - 1 for x in range(20)]
+    steps = [math.exp(x * 1.0 / 20) - 1 for x in range(20)]
     count = int(sum(steps))
-    with click.progressbar(length=count, show_percent=False,
-                           label='Slowing progress bar',
-                           fill_char=click.style(u'█', fg='green')) as bar:
+    with click.progressbar(
+        length=count,
+        show_percent=False,
+        label="Slowing progress bar",
+        fill_char=click.style(u"█", fg="green"),
+    ) as bar:
         for item in steps:
             time.sleep(item)
             bar.update(item)
 
 
 @cli.command()
-@click.argument('url')
+@click.argument("url")
 def open(url):
     """Opens a file or URL In the default application."""
     click.launch(url)
 
 
 @cli.command()
-@click.argument('url')
+@click.argument("url")
 def locate(url):
     """Opens a file or URL In the default application."""
     click.launch(url, locate=True)
@@ -104,16 +118,16 @@ def locate(url):
 @cli.command()
 def edit():
     """Opens an editor with some text in it."""
-    MARKER = '# Everything below is ignored\n'
-    message = click.edit('\n\n' + MARKER)
+    MARKER = "# Everything below is ignored\n"
+    message = click.edit("\n\n{}".format(MARKER))
     if message is not None:
-        msg = message.split(MARKER, 1)[0].rstrip('\n')
+        msg = message.split(MARKER, 1)[0].rstrip("\n")
         if not msg:
-            click.echo('Empty message!')
+            click.echo("Empty message!")
         else:
-            click.echo('Message:\n' + msg)
+            click.echo("Message:\n{}".format(msg))
     else:
-        click.echo('You did not enter anything!')
+        click.echo("You did not enter anything!")
 
 
 @cli.command()
@@ -131,26 +145,26 @@ def pause():
 @cli.command()
 def menu():
     """Shows a simple menu."""
-    menu = 'main'
+    menu = "main"
     while 1:
-        if menu == 'main':
-            click.echo('Main menu:')
-            click.echo('  d: debug menu')
-            click.echo('  q: quit')
+        if menu == "main":
+            click.echo("Main menu:")
+            click.echo("  d: debug menu")
+            click.echo("  q: quit")
             char = click.getchar()
-            if char == 'd':
-                menu = 'debug'
-            elif char == 'q':
-                menu = 'quit'
+            if char == "d":
+                menu = "debug"
+            elif char == "q":
+                menu = "quit"
             else:
-                click.echo('Invalid input')
-        elif menu == 'debug':
-            click.echo('Debug menu')
-            click.echo('  b: back')
+                click.echo("Invalid input")
+        elif menu == "debug":
+            click.echo("Debug menu")
+            click.echo("  b: back")
             char = click.getchar()
-            if char == 'b':
-                menu = 'main'
+            if char == "b":
+                menu = "main"
             else:
-                click.echo('Invalid input')
-        elif menu == 'quit':
+                click.echo("Invalid input")
+        elif menu == "quit":
             return
diff --git a/examples/validation/setup.py b/examples/validation/setup.py
index 9491f70..b7698f6 100644
--- a/examples/validation/setup.py
+++ b/examples/validation/setup.py
@@ -1,15 +1,13 @@
 from setuptools import setup
 
 setup(
-    name='click-example-validation',
-    version='1.0',
-    py_modules=['validation'],
+    name="click-example-validation",
+    version="1.0",
+    py_modules=["validation"],
     include_package_data=True,
-    install_requires=[
-        'click',
-    ],
-    entry_points='''
+    install_requires=["click"],
+    entry_points="""
         [console_scripts]
         validation=validation:cli
-    ''',
+    """,
 )
diff --git a/examples/validation/validation.py b/examples/validation/validation.py
index 00fa0a6..c4f7352 100644
--- a/examples/validation/validation.py
+++ b/examples/validation/validation.py
@@ -1,4 +1,5 @@
 import click
+
 try:
     from urllib import parse as urlparse
 except ImportError:
@@ -7,27 +8,32 @@ except ImportError:
 
 def validate_count(ctx, param, value):
     if value < 0 or value % 2 != 0:
-        raise click.BadParameter('Should be a positive, even integer.')
+        raise click.BadParameter("Should be a positive, even integer.")
     return value
 
 
 class URL(click.ParamType):
-    name = 'url'
+    name = "url"
 
     def convert(self, value, param, ctx):
         if not isinstance(value, tuple):
             value = urlparse.urlparse(value)
-            if value.scheme not in ('http', 'https'):
-                self.fail('invalid URL scheme (%s).  Only HTTP URLs are '
-                          'allowed' % value.scheme, param, ctx)
+            if value.scheme not in ("http", "https"):
+                self.fail(
+                    "invalid URL scheme ({}).  Only HTTP URLs are"
+                    " allowed".format(value.scheme),
+                    param,
+                    ctx,
+                )
         return value
 
 
 @click.command()
-@click.option('--count', default=2, callback=validate_count,
-              help='A positive even number.')
-@click.option('--foo', help='A mysterious parameter.')
-@click.option('--url', help='A URL', type=URL())
+@click.option(
+    "--count", default=2, callback=validate_count, help="A positive even number."
+)
+@click.option("--foo", help="A mysterious parameter.")
+@click.option("--url", help="A URL", type=URL())
 @click.version_option()
 def cli(count, foo, url):
     """Validation.
@@ -36,9 +42,11 @@ def cli(count, foo, url):
     through callbacks, through a custom type as well as by validating
     manually in the function.
     """
-    if foo is not None and foo != 'wat':
-        raise click.BadParameter('If a value is provided it needs to be the '
-                                 'value "wat".', param_hint=['--foo'])
-    click.echo('count: %s' % count)
-    click.echo('foo: %s' % foo)
-    click.echo('url: %s' % repr(url))
+    if foo is not None and foo != "wat":
+        raise click.BadParameter(
+            'If a value is provided it needs to be the value "wat".',
+            param_hint=["--foo"],
+        )
+    click.echo("count: {}".format(count))
+    click.echo("foo: {}".format(foo))
+    click.echo("url: {!r}".format(url))