[Target] Ensure that Target#archs is always initialized as array

lib/cocoapods/installer/target_installer.rb

@@ -67,7 +67,7 @@ module Pod
       def custom_build_settings
         settings = {}
 
-        unless target.nil? || target.archs.empty?
+        unless target.archs.empty?
           settings['ARCHS'] = target.archs
         end
 

lib/cocoapods/target.rb

@@ -16,6 +16,12 @@ module Pod
     attr_accessor :host_requires_frameworks
     alias_method :host_requires_frameworks?, :host_requires_frameworks
 
+    # Initialize a new target
+    #
+    def initialize
+      @archs = []
+    end
+
     # @return [String] the name of the library.
     #
     def name
@@ -105,7 +111,7 @@ module Pod
     #
     attr_accessor :native_target
 
-    # @return [String] The value for the ARCHS build setting.
+    # @return [Array<String>] The value for the ARCHS build setting.
     #
     attr_accessor :archs
 

lib/cocoapods/target/aggregate_target.rb

@@ -13,6 +13,7 @@ module Pod
     # @param [Sandbox] sandbox @see sandbox
     #
     def initialize(target_definition, sandbox)
+      super()
       @target_definition = target_definition
       @sandbox = sandbox
       @pod_targets = []

lib/cocoapods/target/pod_target.rb

@@ -41,6 +41,7 @@ module Pod
     def initialize(specs, target_definitions, sandbox, scoped = false)
       raise "Can't initialize a PodTarget without specs!" if specs.nil? || specs.empty?
       raise "Can't initialize a PodTarget without TargetDefinition!" if target_definitions.nil? || target_definitions.empty?
+      super()
       @specs = specs
       @target_definitions = target_definitions
       @sandbox = sandbox

spec/unit/target/aggregate_target_spec.rb

@@ -13,6 +13,10 @@ module Pod
         @target.target_definition.should == @target_definition
       end
 
+      it 'is initialized with empty archs' do
+        @target.archs.should == []
+      end
+
       it 'returns the label of the target definition' do
         @target.label.should == 'Pods'
       end

spec/unit/target/pod_target_spec.rb

@@ -24,6 +24,10 @@ module Pod
         @pod_target.target_definitions.should == [@target_definition]
       end
 
+      it 'is initialized with empty archs' do
+        @pod_target.archs.should == []
+      end
+
       it 'returns its name' do
         @pod_target.name.should == 'BananaLib'
         @pod_target.scoped.first.name.should == 'Pods-BananaLib'