• There are 35 files with units, with 3,728 lines of code.
• 0 very complex files (McCabe index sum 251+; 0 lines of code)
• 1 complex files (McCabe index sum 126-250; 464 lines of code)
• 8 medium complex files (McCabe index sum 51-125; 1,757 lines of code)
• 9 slightly complex files (McCabe index sum 26-50; 883 lines of code)
• 17 simple files (McCabe index sum 1-25; 624 lines of code)
• 79 main files have no units (e.g. languages without unit analysis, or files without functions) and are not classified.

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
worker.cxx in engine/native	464	19	162	35	38
lok.cxx in engine/wasm-source	335	40	90	27	22
minimize-ui-resources.py in scripts	176	4	72	41	51
fonts.ts in packages/entry/src	335	15	70	21	12
index.ts in packages/entry/src	385	26	69	18	11
wasm.ts in packages/entry/src	210	10	60	29	26
font-metadata-cache.ts in packages/entry/src	85	6	58	68	25
engine.ts in packages/entry/src	145	9	54	37	15
image-operations.ts in packages/entry/src	86	2	51	59	44
ooxml.ts in packages/entry/src	68	2	45	66	44
sheet-geometry.ts in packages/entry/src	85	7	41	48	12
image-renderer.ts in packages/entry/src	109	2	39	36	23
native-image-renderer.ts in packages/entry/src	202	6	36	18	31
rendering.ts in packages/entry/src	68	2	34	50	21
options.ts in packages/entry/src	96	5	32	33	14
operations.ts in packages/entry/src	44	2	29	66	21
font-loader.ts in packages/entry/src	112	5	27	24	12
native.ts in packages/entry/src	99	10	26	26	8
office-fonts.ts in packages/entry/src	53	4	25	47	12
font-cache-compare.py in benchmarks	59	3	20	34	10
document-operations.hxx in engine	46	3	18	39	11
engine-rendering.ts in packages/entry/src	46	4	15	33	7
font-full.ts in packages/entry/src	42	2	14	33	8
png.ts in packages/entry/src	36	2	13	36	11
font-snapshot-state.ts in packages/entry/src	75	2	12	16	6
document.ts in packages/entry/src	22	1	12	55	12
fixtures.py in benchmarks	77	1	5	6	5
errors.ts in packages/entry/src	16	2	4	25	3
font-snapshot-validation.ts in packages/entry/src	14	1	4	29	4
font-snapshot.ts in packages/entry/src	28	1	4	14	4
runtime.ts in packages/entry/src	19	1	2	11	2
font-file-identity.ts in packages/entry/src	9	2	2	22	1
worker.ts in packages/entry/src	68	1	2	3	2
tsdown.config.ts in packages/entry	11	1	1	9	1
profile.ts in packages/entry/src	3	1	1	33	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.