[Installer] Ensure no duplicate target deps are created

CHANGELOG.md

@@ -42,6 +42,10 @@ To install release candidates run `[sudo] gem install cocoapods --pre`
   [Samuel Giddins](https://github.com/segiddins)
   [#3537](https://github.com/CocoaPods/CocoaPods/issues/3537)
 
+* Ensure that no duplicate framework or target dependencies are created.  
+  [Samuel Giddins](https://github.com/segiddins)
+  [#3763](https://github.com/CocoaPods/CocoaPods/issues/3763)
+
 
 ## 0.38.0.beta.1
 

Gemfile.lock

@@ -24,7 +24,7 @@ GIT
 
 GIT
   remote: https://github.com/CocoaPods/Xcodeproj.git
-  revision: e5d74992284d75e25b3a19d02a943133852f0a9f
+  revision: be12faf76853e46ca84767c890feda08415495db
   branch: master
   specs:
     xcodeproj (0.26.0)

lib/cocoapods/installer.rb

@@ -626,7 +626,7 @@ module Pod
               if pod_target.requires_frameworks?
                 product_ref = frameworks_group.files.find { |f| f.path == pod_dependency_target.product_name } ||
                   frameworks_group.new_product_ref_for_target(pod_dependency_target.product_basename, pod_dependency_target.product_type)
-                pod_target.native_target.frameworks_build_phase.add_file_reference(product_ref)
+                pod_target.native_target.frameworks_build_phase.add_file_reference(product_ref, true)
               end
             end
           end

lib/cocoapods/installer/user_project_integrator/target_integrator.rb

@@ -126,7 +126,7 @@ module Pod
             new_product_ref = frameworks.files.find { |f| f.path == target.product_name } ||
               frameworks.new_product_ref_for_target(target_basename, target.product_type)
             build_file = build_phase.build_file(new_product_ref) ||
-              build_phase.add_file_reference(new_product_ref)
+              build_phase.add_file_reference(new_product_ref, true)
             if target.requires_frameworks?
               # Weak link the aggregate target's product, because as it contains
               # no symbols, it isn't copied into the app bundle. dyld will so

lib/cocoapods/target/pod_target.rb

@@ -153,9 +153,9 @@ module Pod
     #         depends.
     #
     def dependencies
-      spec_consumers.map do |consumer|
+      spec_consumers.flat_map do |consumer|
         consumer.dependencies.map { |dep| Specification.root_name(dep.name) }
-      end.flatten
+      end.uniq
     end
 
     # Checks if the target should be included in the build configuration with