  Eye tracking tools are used in software engineering research to study various
software development activities. However, a major limitation of these tools is
their inability to track gaze data for activities that involve source code
editing. We present a novel solution to support eye tracking experiments for
tasks involving source code edits as an extension of the iTrace community
infrastructure. We introduce the iTrace-Atom plugin and gazel -- a Python data
processing pipeline that maps gaze information to changing source code elements
and provides researchers with a way to query this dynamic data. iTrace-Atom is
evaluated via a series of simulations and is over 99% accurate at high
eye-tracking speeds of over 1,000Hz. iTrace and gazel completely revolutionize
the way eye tracking studies are conducted in realistic settings with the
presence of scrolling, context switching, and now editing. This opens the doors
to support many day-to-day software engineering tasks such as bug fixing,
adding new features, and refactoring.
