How does KDevelop's quick open match names??

Okay, this has been bothering me for some time. Can someone explain the
logic behind how Quick Open decides what it thinks you want to open? In
particular, can someone explain why it "prefers" more distant matches,
at least when typing file names?

See attached example. I've typed "options.p", which Quick Open thinks is
a better match for "options_for_QT.cpp", which is a "split" match (if I
divide the input string into three parts, each part matches, in order)
than for "make_options.py", an exact substring match.

I notice this almost constantly; given an input like "abc", Quick Open
almost always "prefers" matches like "qabdcx" (that only match when
additional text is inserted e.g. between 'b' and 'c') over a match like
"abc.x" that not only contains, but *starts with*, the exact string
"abc". Why is this?

-- 
Matthew