Do not raise an exception on a Swift Package dependency

CHANGELOG.md

@@ -32,6 +32,10 @@
   [lemonspike](https://github.com/LemonSpike)
   [#709](https://github.com/CocoaPods/Xcodeproj/issues/709)
 
+* Do not raise an exception on a Swift Package dependency.
+  [Vincent Isambart](https://github.com/vincentisambart)
+  [#743](https://github.com/CocoaPods/Xcodeproj/issues/743)
+
 ##### Bug Fixes
 
 * Fix undefined method 'downcase' for `nil`  

lib/xcodeproj/project/object/target_dependency.rb

@@ -34,9 +34,10 @@ class PBXTargetDependency < AbstractObject
         #
         attribute :platform_filters, Array
 
-        # @return [String] the product reference for this target dependency.
+        # @return [XCSwiftPackageProductDependency] the Swift Package product
+        #         for this target dependency.
         #
-        attribute :product_ref, String
+        has_one :product_ref, XCSwiftPackageProductDependency
 
         public
 
@@ -49,20 +50,22 @@ def display_name
           return name if name
           return target.name if target
           return target_proxy.remote_info if target_proxy
+          return product_ref.product_name if product_ref
         end
 
         def ascii_plist_annotation
           " #{isa} "
         end
 
-        # @return [String] uuid of the target, if the dependency
-        #         is a native target, otherwise the uuid of the
-        #         target in the sub-project if the dependency is
-        #         a target proxy
+        # @return [String] the uuid of the target if the dependency is a native
+        #         target, the uuid of the target in the sub-project if the
+        #         dependency is a target proxy, nil if the dependency is a Swift
+        #         Package.
         #
         def native_target_uuid
           return target.uuid if target
           return target_proxy.remote_global_id_string if target_proxy
+          return nil if product_ref
           raise "Expected target or target_proxy, from which to fetch a uuid for target '#{display_name}'." \
             "Find and clear the PBXTargetDependency entry with uuid '#{@uuid}' in your .xcodeproj."
         end

spec/project/object/target_dependency_spec.rb

@@ -85,6 +85,13 @@ module ProjectSpecs
         @target_dependency.target_proxy = proxy
         @target_dependency.display_name.should == 'Pods'
       end
+
+      it 'returns the product name if needed' do
+        product_ref = @project.new(XCSwiftPackageProductDependency)
+        product_ref.product_name = 'SwiftPackage'
+        @target_dependency.product_ref = product_ref
+        @target_dependency.display_name.should == 'SwiftPackage'
+      end
     end
 
     #----------------------------------------#
@@ -111,10 +118,19 @@ module ProjectSpecs
         @target_dependency.native_target_uuid.should == @target_dependency.target.uuid
       end
 
-      it "raises if target and target_proxy aren't set" do
+      it 'returns nil for a Swift Package product' do
+        product_ref = @project.new(XCSwiftPackageProductDependency)
+        product_ref.product_name = 'SwiftPackage'
+
+        @target_dependency.product_ref = product_ref
+        @target_dependency.native_target_uuid.nil?.should == true
+      end
+
+      it "raises if target, target_proxy, and product_ref aren't set" do
         @target_dependency.name = 'TargetName'
         @target_dependency.target.nil?.should == true
         @target_dependency.target_proxy.nil?.should == true
+        @target_dependency.product_ref.nil?.should == true
         should.raise do
           @target_dependency.native_target_uuid
         end.message.should.include "Expected target or target_proxy, from which to fetch a uuid for target 'TargetName'." \