• There are 35 files with units, with 1,226 lines of code.
• 0 very complex files (McCabe index sum 251+; 0 lines of code)
• 0 complex files (McCabe index sum 126-250; 0 lines of code)
• 1 medium complex files (McCabe index sum 51-125; 302 lines of code)
• 2 slightly complex files (McCabe index sum 26-50; 178 lines of code)
• 32 simple files (McCabe index sum 1-25; 746 lines of code)

The McCabe index of a file grows with its size: per 100 lines tells a large but plain file from a dense one, and most complex unit whether the complexity sits in one unit or is spread over many.

File	# lines	# units	McCabe index (sum)	per 100 lines	most complex unit
Promise.js in core	302	38	64	21	5
Array.js in compatibility	92	4	31	34	14
state.js in core	86	7	28	33	10
facebook.js in sharing	83	8	17	20	4
addWheelListener.js in compatibility	51	5	15	29	6
deepEqual.js in core	44	1	14	32	14
analytics.js in root	49	8	12	24	2
csvToJson.js in data	48	1	12	25	12
events.js in core	32	5	10	31	3
requestAnimationFrame.js in compatibility	31	4	9	29	6
Function.js in compatibility	21	4	8	38	3
throttle.js in timing	35	2	7	20	6
get.js in ajax	29	3	7	24	3
twitter.js in sharing	46	2	6	13	3
csvToArray.js in data	34	1	6	18	6
group.js in data	21	1	6	29	6
getNode.js in sharing	17	1	5	29	5
find.js in array	17	2	5	29	4
pad.js in string	22	1	5	23	5
reindex.js in data	20	1	5	25	5
email.js in sharing	28	2	4	14	2
extend.js in core	15	1	4	27	4
uid.js in core	13	1	3	23	3
preload.js in image	15	3	3	20	1
Date.js in compatibility	8	1	2	25	2
loopForever.js in timing	11	2	2	18	1
isVisible.js in dom	7	1	2	29	2
cancelAnimationFrame.js in compatibility	5	1	1	20	1
touch.js in detect	4	1	1	25	1
compatibility.js in root	8	1	1	13	1
forceRedraw.js in dom	8	1	1	13	1
qsa.js in dom	6	1	1	17	1
qs.js in dom	6	1	1	17	1
addCommas.js in string	6	1	1	17	1
toTitleCase.js in string	6	1	1	17	1

• File complexity is the sum of the McCabe indexes (conditional complexity) of the units (methods, functions...) in a file.
• Files are classified in five categories based on that sum: 1-25 (simple files), 26-50 (slightly complex files), 51-125 (medium complex files), 126-250 (complex files), 251+ (very complex files). The default bands are five times the unit complexity bands, as a file is a group of units.
• Only main code files with units are classified. Files without units (languages without unit analysis, or files without functions) have no complexity to measure and are left out rather than counted as simple.
• A very complex file holds many decisions, which often means it has too many responsibilities: a candidate to split, and a place where changes need more testing.