Make the WheelCache FormatControl argument optional

This commit does not change behaviour, but makes the fact
that --no-binary does not disable the cache anymore (when
always-install-via-wheel is set) more explicit.

src/pip/_internal/cache.py

@@ -231,8 +231,10 @@ class WheelCache(Cache):
  when a certain link is not found in the simple wheel cache first.
  """
 
- def __init__(self, cache_dir, format_control):
- # type: (str, FormatControl) -> None
+ def __init__(self, cache_dir, format_control=None):
+ # type: (str, Optional[FormatControl]) -> None
+ if format_control is None:
+ format_control = FormatControl()
  super().__init__(cache_dir, format_control, {'binary'})
  self._wheel_cache = SimpleWheelCache(cache_dir, format_control)
  self._ephem_cache = EphemWheelCache(format_control)

src/pip/_internal/commands/install.py

@@ -275,7 +275,12 @@ def run(self, options, args):
  target_python=target_python,
  ignore_requires_python=options.ignore_requires_python,
  )
- wheel_cache = WheelCache(options.cache_dir, options.format_control)
+ if "always-install-via-wheel" in options.features_enabled:
+ wheel_cache = WheelCache(options.cache_dir)
+ else:
+ # TODO when removing this branch, also remove format control support
+ # in WheelCache.
+ wheel_cache = WheelCache(options.cache_dir, options.format_control)
 
  req_tracker = self.enter_context(get_requirement_tracker())
 

src/pip/_internal/commands/wheel.py

@@ -103,7 +103,12 @@ def run(self, options, args):
  session = self.get_default_session(options)
 
  finder = self._build_package_finder(options, session)
- wheel_cache = WheelCache(options.cache_dir, options.format_control)
+ if "always-install-via-wheel" in options.features_enabled:
+ wheel_cache = WheelCache(options.cache_dir)
+ else:
+ # TODO when removing this branch, also remove format control support
+ # in WheelCache.
+ wheel_cache = WheelCache(options.cache_dir, options.format_control)
 
  options.wheel_dir = normalize_path(options.wheel_dir)
  ensure_dir(options.wheel_dir)