• File size measurements show the distribution of size of files.
• Files are classified in four categories based on their size (lines of code): 1-100 (very small files), 101-200 (small files), 201-500 (medium size files), 501-1000 (long files), 1001+(very long files).
• It is a good practice to keep files small. Long files may become "bloaters", code that have increased to such gargantuan proportions that they are hard to work with.

• There are 490 files with 240,473 lines of code.
• 50 very long files (147,537 lines of code)
• 55 long files (39,560 lines of code)
• 106 medium size files (33,950 lines of codeclsfd_ftr_w_mp_ins)
• 66 small files (9,393 lines of code)
• 213 very small files (10,033 lines of code)

There are 390 files with lines longer than 120 characters. In total, there are 14609 long lines.

File	# lines	# units	# long lines
checker.ts in src/compiler	35866	2160	3669
types.ts in src/compiler	6196	1	363
fourslashImpl.ts in src/harness	3844	301	362
nodeFactory.ts in src/compiler/factory	5397	477	346
program.ts in src/compiler	3356	188	337
parser.ts in src/compiler	7108	518	331
utilities.ts in src/compiler	6035	660	313
moduleNameResolver.ts in src/compiler	1874	132	213
completions.ts in src/services	3183	161	213
session.ts in src/server	2838	228	184
es2015.ts in src/compiler/transformers	2852	155	181
commandLineParser.ts in src/compiler	3054	133	177
emitter.ts in src/compiler	4796	411	177
findAllReferences.ts in src/services	1751	107	174
binder.ts in src/compiler	2802	183	168
editorServices.ts in src/server	3091	169	156
rules.ts in src/services/formatting	643	68	155
utilities.ts in src/services	2525	281	150
services.ts in src/services	2203	204	149
textChanges.ts in src/services	1224	134	136
importFixes.ts in src/services/codefixes	1085	69	135
declarations.ts in src/compiler/transformers	1526	74	117
tsbuildPublic.ts in src/compiler	1792	86	106
projectReferenceCompileOnSave.ts in src/testRunner/unittests/tsserver	1993	10	92
builder.ts in src/compiler	962	52	91
core.ts in src/compiler	1709	185	85
deprecations.ts in src/deprecatedCompat	620	-	84
extractSymbol.ts in src/services/refactors	1544	65	84
project.ts in src/server	1907	151	82
stringCompletions.ts in src/services	603	47	82
reuseProgramStructure.ts in src/testRunner/unittests	1058	28	82
classFields.ts in src/compiler/transformers	1710	75	78
compileOnSave.ts in src/testRunner/unittests/tsserver	955	18	78
projectReferencesSourcemap.ts in src/testRunner/unittests/tsserver	3769	121	78
resolutionCache.ts in src/compiler	779	47	77
diagnostics.ts in src/compiler/transformers/declarations	432	18	77
fixAddMissingMember.ts in src/services/codefixes	515	22	77
inferFromUsage.ts in src/services/codefixes	966	58	77
moduleSpecifiers.ts in src/compiler	688	41	76
moveToNewFile.ts in src/services/refactors	743	52	74
resolutionCache.ts in src/testRunner/unittests/tsserver	798	17	74
utilities.ts in src/compiler/factory	875	86	72
signatureHelp.ts in src/services	488	38	71
module.ts in src/compiler/transformers/module	1432	62	70
harnessIO.ts in src/harness	1179	65	70
textChanges.ts in src/testRunner/unittests/services	746	24	67
ts.ts in src/compiler/transformers	2067	149	66
convertToAsyncFunction.ts in src/services/codefixes	615	49	66
moduleResolution.ts in src/testRunner/unittests	1373	37	64
sys.ts in src/compiler	1614	107	60