Clean up code style changes

Toward minimizing style changes in the overall PR diff, or toward
consistency with the future use of black (in cases where I wasn't sure
of a good way to minimize the diff).

src/pip/_internal/cache.py

@@ -230,7 +230,8 @@ class SimpleWheelCache(Cache):
                 logger.debug(
                     "Ignoring cached wheel %s for %s as it "
                     "does not match the expected distribution name %s.",
-                    wheel_name, link, package_name)
+                    wheel_name, link, package_name,
+                )
                 continue
             if not wheel.supported(supported_tags):
                 # Built for a different python/arch/etc

src/pip/_internal/commands/cache.py

@@ -59,8 +59,10 @@ class CacheCommand(Command):
 
         # Determine action
         if not args or args[0] not in handlers:
-            logger.error("Need an action (%s) to perform.",
-                         ", ".join(sorted(handlers)))
+            logger.error(
+                "Need an action (%s) to perform.",
+                ", ".join(sorted(handlers)),
+            )
             return ERROR
 
         action = args[0]

src/pip/_internal/commands/configuration.py

@@ -105,8 +105,10 @@ class ConfigurationCommand(Command):
 
         # Determine action
         if not args or args[0] not in handlers:
-            logger.error("Need an action (%s) to perform.",
-                         ", ".join(sorted(handlers)))
+            logger.error(
+                "Need an action (%s) to perform.",
+                ", ".join(sorted(handlers)),
+            )
             return ERROR
 
         action = args[0]
@@ -265,8 +267,9 @@ class ConfigurationCommand(Command):
         try:
             self.configuration.save()
         except Exception:
-            logger.exception("Unable to save configuration. "
-                             "Please report this as a bug.")
+            logger.exception(
+                "Unable to save configuration. Please report this as a bug."
+            )
             raise PipError("Internal Error.")
 
     def _determine_editor(self, options):

src/pip/_internal/index/collector.py

@@ -529,7 +529,8 @@ def group_locations(locations, expand_dir=False):
                     urls.append(url)
                 else:
                     logger.warning(
-                        "Path '%s' is ignored: it is a directory.", path)
+                        "Path '%s' is ignored: it is a directory.", path,
+                    )
             elif os.path.isfile(path):
                 sort_path(path)
             else:

src/pip/_internal/req/constructors.py

@@ -173,8 +173,9 @@ def deduce_helpful_msg(req):
                     " the packages specified within it."
                 ).format(req)
         except RequirementParseError:
-            logger.debug("Cannot parse '%s' as requirements file",
-                         req, exc_info=True)
+            logger.debug(
+                "Cannot parse '%s' as requirements file", req, exc_info=True
+            )
     else:
         msg += " File '{}' does not exist.".format(req)
     return msg

src/pip/_internal/req/req_uninstall.py

@@ -612,7 +612,8 @@ class UninstallPthEntries(object):
         # If the file doesn't exist, log a warning and return
         if not os.path.isfile(self.file):
             logger.warning(
-                "Cannot remove entries from nonexistent file %s", self.file)
+                "Cannot remove entries from nonexistent file %s", self.file
+            )
             return
         with open(self.file, 'rb') as fh:
             # windows uses '\r\n' with py3k, but uses '\n' with py2.x

src/pip/_internal/utils/compat.py

@@ -121,8 +121,11 @@ def str_to_display(data, desc=None):
     try:
         decoded_data = data.decode(encoding)
     except UnicodeDecodeError:
-        logger.warning('%s does not appear to be encoded as %s',
-                       desc or 'Bytes object', encoding)
+        logger.warning(
+            '%s does not appear to be encoded as %s',
+            desc or 'Bytes object',
+            encoding,
+        )
         decoded_data = data.decode(encoding, errors=backslashreplace_decode)
 
     # Make sure we can print the output, by encoding it to the output

src/pip/_internal/utils/subprocess.py

@@ -241,8 +241,12 @@ def call_subprocess(
             ).format(proc.returncode, command_desc)
             raise InstallationError(exc_msg)
         elif on_returncode == 'warn':
-            subprocess_logger.warning('Command "%s" had error code %s in %s',
-                                      command_desc, proc.returncode, cwd)
+            subprocess_logger.warning(
+                'Command "%s" had error code %s in %s',
+                command_desc,
+                proc.returncode,
+                cwd,
+            )
         elif on_returncode == 'ignore':
             pass
         else:

src/pip/_internal/utils/temp_dir.py

@@ -183,7 +183,8 @@ class TempDirectory(object):
         # scripts, so we canonicalize the path by traversing potential
         # symlinks here.
         path = os.path.realpath(
-            tempfile.mkdtemp(prefix="pip-{}-".format(kind)))
+            tempfile.mkdtemp(prefix="pip-{}-".format(kind))
+        )
         logger.debug("Created temporary directory: %s", path)
         return path
 
@@ -266,7 +267,8 @@ class AdjacentTempDirectory(TempDirectory):
         else:
             # Final fallback on the default behavior.
             path = os.path.realpath(
-                tempfile.mkdtemp(prefix="pip-{}-".format(kind)))
+                tempfile.mkdtemp(prefix="pip-{}-".format(kind))
+            )
 
         logger.debug("Created temporary directory: %s", path)
         return path