[Resolver] Add filtering for subspecs included via subspec_dependencies

Gemfile

@@ -15,7 +15,7 @@ gem 'json', '1.7.7'
 
 group :development do
   cp_gem 'claide',               'CLAide'
-  cp_gem 'cocoapods-core',       'Core'
+  cp_gem 'cocoapods-core',       'Core', 'seg-from-subspec-dependencies'
   cp_gem 'cocoapods-downloader', 'cocoapods-downloader'
   cp_gem 'cocoapods-plugins',    'cocoapods-plugins'
   cp_gem 'cocoapods-trunk',      'cocoapods-trunk'
@@ -44,4 +44,3 @@ group :debugging do
   gem 'pry'
   gem 'ruby-prof'
 end
-

Gemfile.lock

@@ -7,8 +7,8 @@ GIT
 
 GIT
   remote: https://github.com/CocoaPods/Core.git
-  revision: 8b554d8dd184e75bb79dcc86a7056e9fef35e952
-  branch: master
+  revision: afa6cd5ea769a8044d36a002f7e1e2ec2710da00
+  branch: seg-from-subspec-dependencies
   specs:
     cocoapods-core (0.34.4)
       activesupport (>= 3.2.15)
@@ -17,7 +17,7 @@ GIT
 
 GIT
   remote: https://github.com/CocoaPods/Molinillo.git
-  revision: 67d09200c8baca9547f54a0145b405c658e0ba07
+  revision: e86cec392a75c577f2c803d8cc87debe41a9bdbe
   branch: master
   specs:
     molinillo (0.1.0)

lib/cocoapods/resolver.rb

@@ -68,9 +68,20 @@ module Pod
         specs_by_target = {}
         podfile.target_definition_list.each do |target|
           specs = target.dependencies.map(&:name).map do |name|
+            s = lambda do |node|
+              d_nodes = node.outgoing_edges.select do |edge|
+                edge.requirements.any? do |dependency|
+                  !dependency.from_subspec_dependency? || edge.destination.payload.available_platforms.any? { |p| target.platform.supports?(p) }
+                end
+              end.map(&:destination)
+
+              d_nodes + d_nodes.flat_map { |n| s.call(n) }
+            end
+
             node = @activated.vertex_named(name)
-            (node.recursive_successors << node).to_a
+            s.call(node).to_a << node
           end
+
           specs_by_target[target] = specs.
             flatten.
             map(&:payload).