check: check and use all available distributions

Not only the local ones.
Fix #4083

CHANGES.txt

@@ -4,6 +4,9 @@
   uses the correct setting name (``format``) rather than the incorrect one
   (``list_format``) (:issue:`4058`).
 
+* Fix ``pip check`` to check all available distributions and not just the
+  local ones (:issue:`4083`).
+
 
 **9.0.0 (2016-11-02)**
 

pip/commands/check.py

 import logging
 
 from pip.basecommand import Command
-from pip.operations.check import (
-    check_requirements, get_installed_distributions)
+from pip.operations.check import check_requirements
+from pip.utils import get_installed_distributions
 
 
 logger = logging.getLogger(__name__)
@@ -16,10 +16,10 @@ class CheckCommand(Command):
     summary = 'Verify installed packages have compatible dependencies.'
 
     def run(self, options, args):
-        installed = get_installed_distributions(skip=())
-        missing_reqs_dict, incompatible_reqs_dict = check_requirements()
+        dists = get_installed_distributions(local_only=False, skip=())
+        missing_reqs_dict, incompatible_reqs_dict = check_requirements(dists)
 
-        for dist in installed:
+        for dist in dists:
             key = '%s==%s' % (dist.project_name, dist.version)
 
             for requirement in missing_reqs_dict.get(key, []):

pip/operations/check.py

-from pip.utils import get_installed_distributions
 
 
-def check_requirements():
-    installed = get_installed_distributions(skip=())
+def check_requirements(installed_dists):
     missing_reqs_dict = {}
     incompatible_reqs_dict = {}
 
-    for dist in installed:
+    for dist in installed_dists:
         key = '%s==%s' % (dist.project_name, dist.version)
 
-        missing_reqs = list(get_missing_reqs(dist, installed))
+        missing_reqs = list(get_missing_reqs(dist, installed_dists))
         if missing_reqs:
             missing_reqs_dict[key] = missing_reqs
 
-        incompatible_reqs = list(get_incompatible_reqs(dist, installed))
+        incompatible_reqs = list(get_incompatible_reqs(
+            dist, installed_dists))
         if incompatible_reqs:
             incompatible_reqs_dict[key] = incompatible_reqs