Fix for https://github.com/CocoaPods/CocoaPods/issues/141

lib/cocoapods/dependency.rb

@@ -19,7 +19,7 @@ module Pod
 
       elsif !name_and_version_requirements.empty? && block.nil?
         if name_and_version_requirements.last.is_a?(Hash)
-          @external_source = ExternalSources.from_params(name_and_version_requirements[0], name_and_version_requirements.pop)
+          @external_source = ExternalSources.from_params(name_and_version_requirements[0].split('/').first, name_and_version_requirements.pop)
         end
         super(*name_and_version_requirements)
 

lib/cocoapods/resolver.rb

@@ -49,7 +49,11 @@ module Pod
           # that's being used behind the scenes, but passing it anyways for
           # completeness sake.
           specification = external_source.specification_from_sandbox(@sandbox, platform)
-          Specification::Set::External.new(specification)
+          set = Specification::Set::External.new(specification)
+          if dependency.subspec_dependency?
+            @cached_sets[dependency.top_level_spec_name] ||= set
+          end
+          set
         else
           @cached_sources.search(dependency)
         end

spec/unit/podfile_spec.rb

@@ -25,6 +25,14 @@ describe "Pod::Podfile" do
     dep = podfile.dependency_by_top_level_spec_name('SomeExternalPod')
     dep.external_source.params.should == { :git => 'GIT-URL', :commit => '1234' }
   end
+  
+  it "adds a subspec dependency on a Pod repo outside of a spec repo (the repo is expected to contain a podspec)" do
+    podfile = Pod::Podfile.new do
+      dependency 'MainSpec/FirstSubSpec', :git => 'GIT-URL', :commit => '1234'
+    end
+    dep = podfile.dependency_by_top_level_spec_name('MainSpec')
+    dep.external_source.name.should == 'MainSpec'
+  end
 
   it "adds a dependency on a library outside of a spec repo (the repo does not need to contain a podspec)" do
     podfile = Pod::Podfile.new do

spec/unit/resolver_spec.rb

@@ -90,5 +90,35 @@ describe "Pod::Resolver" do
       cocoa-oauth
     }
   end
+  
+  it "resolves subspecs with external constraints" do
+    @podfile = Pod::Podfile.new do
+      platform :ios
+      dependency 'MainSpec/FirstSubSpec', :git => 'GIT-URL'
+    end
+    spec = Pod::Spec.new do |s|
+      s.name    = 'MainSpec'
+      s.version = '1.2.3'
+      s.platform = :ios
+      s.license = 'MIT'
+      s.author = 'Joe the Plumber'
+      s.summary = 'A spec with subspecs'
+      s.source  = { :git => '/some/url' }
+      s.requires_arc = true
+
+      s.subspec 'FirstSubSpec' do |fss|
+        fss.source_files = 'some/file'
+
+        fss.subspec 'SecondSubSpec' do |sss|
+        end
+      end
+    end
+    @podfile.dependencies.first.external_source.stubs(:specification_from_sandbox).returns(spec)
+    resolver = Pod::Resolver.new(@podfile, stub('sandbox'))
+    resolver.resolve.values.flatten.map(&:name).sort.should == %w{
+      MainSpec
+      MainSpec/FirstSubSpec
+    }
+  end
 end