Fix platform specifications not being used when resolving dependencies

CHANGELOG.md

@@ -17,6 +17,7 @@
 - Fixed python restricted dependencies not being checked agaisnt virtualenv version.
 - Fixed python restricted dependencies not being checked agaisnt virtualenv version.
 - Fixed python/platform constraint not being picked up for subdependencies.
 - Fixed python/platform constraint not being picked up for subdependencies.
 - Fixed skipped packages appearing as installing.
 - Fixed skipped packages appearing as installing.
+- Fixed platform specification not being used when resolving dependencies.
 
 
 
 
 ## [0.4.2] - 2018-03-10
 ## [0.4.2] - 2018-03-10

poetry/packages/constraints/platform_constraint.py

@@ -50,11 +50,14 @@ class PlatformConstraint(BaseConstraint):
         return self._platform
         return self._platform
 
 
     def matches(self, provider):
     def matches(self, provider):
-        if not isinstance(provider, PlatformConstraint):
+        if not isinstance(provider, (PlatformConstraint, EmptyConstraint)):
             raise ValueError(
             raise ValueError(
                 'Platform constraints can only be compared with each other'
                 'Platform constraints can only be compared with each other'
             )
             )
 
 
+        if isinstance(provider, EmptyConstraint):
+            return True
+
         is_equal_op = self.OP_EQ is self._operator
         is_equal_op = self.OP_EQ is self._operator
         is_non_equal_op = self.OP_NE is self._operator
         is_non_equal_op = self.OP_NE is self._operator
         is_provider_equal_op = self.OP_EQ is provider.operator
         is_provider_equal_op = self.OP_EQ is provider.operator

poetry/puzzle/provider.py

@@ -179,7 +179,10 @@ class Provider(SpecificationProvider):
             if not any([r.allows_prereleases() for r in vertex.requirements]):
             if not any([r.allows_prereleases() for r in vertex.requirements]):
                 return False
                 return False
 
 
-        return self._package.python_constraint.matches(package.python_constraint)
+        return (
+            self._package.python_constraint.matches(package.python_constraint)
+            and self._package.platform_constraint.matches(package.platform_constraint)
+        )
 
 
     def sort_dependencies(self,
     def sort_dependencies(self,
                           dependencies: List[Dependency],
                           dependencies: List[Dependency],

tests/puzzle/test_solver.py

@@ -326,6 +326,36 @@ def test_solver_solves_optional_and_compatible_packages(solver, repo, package):
     ])
     ])
 
 
 
 
+def test_solver_solves_while_respecting_root_platforms(solver, repo, package):
+    package.platform = 'darwin'
+    package_a = get_package('A', '1.0')
+    package_b = get_package('B', '1.0')
+    package_b.python_versions = '^3.6'
+    package_c12 = get_package('C', '1.2')
+    package_c12.platform = 'win32'
+    package_c10 = get_package('C', '1.0')
+    package_c10.platform = 'darwin'
+    package_b.add_dependency('C', '^1.0')
+
+    repo.add_package(package_a)
+    repo.add_package(package_b)
+    repo.add_package(package_c10)
+    repo.add_package(package_c12)
+
+    request = [
+        get_dependency('A'),
+        get_dependency('B')
+    ]
+
+    ops = solver.solve(request)
+
+    check_solver_result(ops, [
+        {'job': 'install', 'package': package_c10},
+        {'job': 'install', 'package': package_b},
+        {'job': 'install', 'package': package_a},
+    ])
+
+
 def test_solver_does_not_return_extras_if_not_requested(solver, repo):
 def test_solver_does_not_return_extras_if_not_requested(solver, repo):
     package_a = get_package('A', '1.0')
     package_a = get_package('A', '1.0')
     package_b = get_package('B', '1.0')
     package_b = get_package('B', '1.0')