Add Podfile#target which scopes dependencies to static libraries.

lib/cocoapods/podfile.rb

 module Pod
   class Podfile
+    class Target
+      attr_reader :name, :parent, :target_dependencies
+
+      def initialize(name, parent = nil)
+        @name, @parent, @target_dependencies = name, parent, []
+      end
+
+      def lib_name
+        name == :default ? "libPods" : "libPods-#{name}"
+      end
+
+      # Returns *all* dependencies of this target, not only the target specific
+      # ones in `target_dependencies`.
+      def dependencies
+        @target_dependencies + (@parent ? @parent.dependencies : [])
+      end
+    end
+
     def self.from_file(path)
       podfile = Podfile.new do
         eval(path.read, nil, path.to_s)
@@ -10,7 +28,7 @@ module Pod
     end
 
     def initialize(&block)
-      @dependencies = []
+      @targets = { :default => (@target = Target.new(:default)) }
       instance_eval(&block)
     end
 
@@ -58,10 +76,12 @@ module Pod
     # * http://semver.org
     # * http://docs.rubygems.org/read/chapter/7
     def dependency(name, *version_requirements)
-      @dependencies << Dependency.new(name, *version_requirements)
+      @target.target_dependencies << Dependency.new(name, *version_requirements)
     end
 
-    attr_reader :dependencies
+    def dependencies
+      @targets.values.map(&:target_dependencies).flatten
+    end
 
     # Specifies that a BridgeSupport metadata should be generated from the
     # headers of all installed Pods.
@@ -72,6 +92,15 @@ module Pod
       @generate_bridge_support = true
     end
 
+    attr_reader :targets
+
+    def target(name, options = {})
+      @targets[name] = @target = Target.new(name, @target)
+      yield
+    ensure
+      @target = @target.parent
+    end
+
     # This is to be compatible with a Specification for use in the Installer and
     # Resolver.
 
@@ -86,13 +115,13 @@ module Pod
     end
 
     def dependency_by_name(name)
-      @dependencies.find { |d| d.name == name }
+      dependencies.find { |d| d.name == name }
     end
 
     def validate!
       lines = []
       lines << "* the `platform` attribute should be either `:osx` or `:ios`" unless [:osx, :ios].include?(@platform)
-      lines << "* no dependencies were specified, which is, well, kinda pointless" if @dependencies.empty?
+      lines << "* no dependencies were specified, which is, well, kinda pointless" if dependencies.empty?
       raise(Informative, (["The Podfile at `#{@defined_in_file}' is invalid:"] + lines).join("\n")) unless lines.empty?
     end
   end

spec/unit/podfile_spec.rb

@@ -23,6 +23,41 @@ describe "Pod::Podfile" do
     podfile.generate_bridge_support?.should == true
   end
 
+  describe "concerning targets (dependency groups)" do
+    before do
+      @podfile = Pod::Podfile.new do
+        target :debug do
+          dependency 'SSZipArchive'
+        end
+
+        target :test, :exclusive => true do
+          dependency 'JSONKit'
+        end
+
+        dependency 'ASIHTTPRequest'
+      end
+    end
+
+    it "returns all dependencies of all targets combined, which is used during resolving to enusre compatible dependencies" do
+      @podfile.dependencies.map(&:name).sort.should == %w{ ASIHTTPRequest JSONKit SSZipArchive }
+    end
+
+    it "adds dependencies outside of any explicit target block to the default target" do
+      target = @podfile.targets[:default]
+      target.lib_name.should == 'libPods'
+      target.dependencies.should == [Pod::Dependency.new('ASIHTTPRequest')]
+    end
+
+    it "adds dependencies of the outer target to non-exclusive targets" do
+      target = @podfile.targets[:debug]
+      target.lib_name.should == 'libPods-debug'
+      target.dependencies.sort_by(&:name).should == [
+        Pod::Dependency.new('ASIHTTPRequest'),
+        Pod::Dependency.new('SSZipArchive')
+      ]
+    end
+  end
+
   describe "concerning validations" do
     it "raises if no platform is specified" do
       exception = lambda {