Experimental implementation of supporting [] disabling default extras

Author: astrofrog

src/pip/_internal/req/constructors.py

@@ -31,10 +31,13 @@
 from pip._internal.utils.urls import path_to_url
 from pip._internal.vcs import is_url, vcs
 
+EXPLICIT_EMPTY_EXTRAS = 'explicit-no-default-extras'
+
 __all__ = [
     "install_req_from_editable",
     "install_req_from_line",
     "parse_editable",
+    "EXPLICIT_EMPTY_EXTRAS"
 ]
 
 logger = logging.getLogger(__name__)
@@ -48,7 +51,11 @@ def _strip_extras(path: str) -> Tuple[str, Optional[str]]:
         path_no_extras = m.group(1)
         extras = m.group(2)
     else:
-        path_no_extras = path
+        if '[]' in path:
+            extras = f'[{EXPLICIT_EMPTY_EXTRAS}]'
+            path_no_extras = path.replace('[]', '')
+        else:
+            path_no_extras = path
 
     return path_no_extras, extras
 

src/pip/_internal/resolution/legacy/resolver.py

@@ -38,6 +38,7 @@
     InstallRequirement,
     check_invalid_constraint_type,
 )
+from pip._internal.req.constructors import EXPLICIT_EMPTY_EXTRAS
 from pip._internal.req.req_set import RequirementSet
 from pip._internal.resolution.base import BaseResolver, InstallRequirementProvider
 from pip._internal.utils import compatibility_tags
@@ -552,12 +553,13 @@ def add_req(subreq: Requirement, extras_requested: Iterable[str]) -> None:
                     set(req_to_install.extras) - set(dist.iter_provided_extras())
                 )
                 for missing in missing_requested:
-                    logger.warning(
-                        "%s %s does not provide the extra '%s'",
-                        dist.raw_name,
-                        dist.version,
-                        missing,
-                    )
+                    if missing != EXPLICIT_EMPTY_EXTRAS:
+                        logger.warning(
+                            "%s %s does not provide the extra '%s'",
+                            dist.raw_name,
+                            dist.version,
+                            missing,
+                        )
 
                 available_requested = sorted(
                     set(dist.iter_provided_extras()) & set(req_to_install.extras)

src/pip/_internal/resolution/resolvelib/candidates.py

@@ -21,6 +21,7 @@
     install_req_from_line,
 )
 from pip._internal.req.req_install import InstallRequirement
+from pip._internal.req.constructors import EXPLICIT_EMPTY_EXTRAS
 from pip._internal.utils.direct_url_helpers import direct_url_from_link
 from pip._internal.utils.misc import normalize_version_info
 
@@ -515,12 +516,13 @@ def iter_dependencies(self, with_requires: bool) -> Iterable[Optional[Requiremen
         valid_extras = self.extras.intersection(self.base.dist.iter_provided_extras())
         invalid_extras = self.extras.difference(self.base.dist.iter_provided_extras())
         for extra in sorted(invalid_extras):
-            logger.warning(
-                "%s %s does not provide the extra '%s'",
-                self.base.name,
-                self.version,
-                extra,
-            )
+            if extra != EXPLICIT_EMPTY_EXTRAS:
+                logger.warning(
+                    "%s %s does not provide the extra '%s'",
+                    self.base.name,
+                    self.version,
+                    extra,
+                )
 
         for r in self.base.dist.iter_dependencies(valid_extras):
             yield from factory.make_requirements_from_spec(