title: Why can't I import Pod Unit Tests file into host application Unit Tests file
body: <p>I have a project which depends on a cocoapod dependency, this dependency has a Unit Tests target that contains some mocking files I want to use in the tests of my host application.
  Example:</p>
  
  <pre><code>@import testable MyPod_Unit_Tests
  class HostApplicationTestCase: XCTestCase {
      func setup() {
          let mockObj = UsefulPodMockObject()
  ....
  </code></pre>
  
  <p>then I get the following building error:</p>
  
  <blockquote>
    <p>ld: warning: directory not found for option '-F/Users/macuser/dev/projs/HostProject/Pods/pod-library/pod-library/Frameworks'
    ld: warning: Could not find or use auto-linked framework 'RandomCocoapodsDependencyFromPodfile'
    Undefined symbols for architecture x86_64:
      "MyPod_Unit_Tests.UsefulPodMockObject.init() -> MyPod_Unit_Tests.UsefulPodMockObject", referenced from:
          closure #1 () -> () in HostApplicationUnitTests.HostApplicationTestsCase.spec() -> () in HostApplicationTestsCase.o
    ld: symbol(s) not found for architecture x86_64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)</p>
  </blockquote>
  
  <p>Thanks in advance.</p>