If browser is disconnected and not all tests run then it looks like all tests passed about karma-junit-reporter

[davidparsson]

That may actually be an issue on Jenkins' end. This reporter produces errors="1" on the testsuite tag in the XML report when a browser is disconnected.

See the full example below, produced by karma-junit-runner version 0.2.2, which is the latest version at time of writing:

<?xml version="1.0"?>
<testsuites>
  <testsuite name="PhantomJS 1.9.8 (Mac OS X)" package="tests" timestamp="2015-02-27T10:18:20" id="0" hostname="localhost" tests="1" errors="1" failures="0" time="0">
    <properties>
      <property name="browser.fullName" value="Mozilla/5.0 (Macintosh; Intel Mac OS X) AppleWebKit/534.34 (KHTML, like Gecko) PhantomJS/1.9.8 Safari/534.34"/>
    </properties>
    <system-out><![CDATA[
]]></system-out>
    <system-err/>
  </testsuite>
</testsuites>

[davidparsson]

Jenkins ignores the errors attribute on the testsuite tag, but adding an error tag will make Jenkins see this error.