Xcode 9 - Test target X encountered an error (Unable to connect to Test Manager) : <p>I'm trying to run some of my Unit Tests but it kept giving me error:</p>

<pre><code>Showing Recent Issues
Test target X encountered an error (Unable to connect to test manager on d7306c4130298fbc17bc0985ec02f808dcdc1374 If you believe this error represents a bug, please attach the log file at /var/folders/2h/0y4yjs6s7l307mbr6pk1xdl00000gn/T/com.apple.dt.XCTest/IDETestRunSession-CF80FA05-C8ED-4FCE-A04B-4A8070F21059/X-E8F39B10-0CDC-43D5-9BED-CD2D0F6081DA/Session-X-2018-01-08_161733-D3YlRc.log)
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<p>I've tried searching for this type of error but to no avail. Anybody got any ideas? </p>
