1	const NEWLINE = /\r?\n/;
2	const WHITE_SPACE = /[\t\f\v ]+/;
3	const ANYTHING = /[^\r\n]+/;
4
5	module.exports = grammar({
6	name: "gitdiff",
7
8	extras: ($) => [WHITE_SPACE],
9
10	rules: {
11	source: ($) => repeat(seq($._line, NEWLINE)),
12
13	_line: ($) =>
14	choice(
15	$.command,
16	$.file_change,
17	$.binary_change,
18	$.index,
19	$.similarity,
20	$.file,
21	$.location,
22	$.addition,
23	$.deletion,
24	$.context
25	),
26
27	command: ($) => iseq("diff", "--git", $.filename),
28
29	file_change: ($) =>
30	iseq(
31	field("kind", choice("new", "deleted", "rename")),
32	choice(
33	seq("file", "mode", $.mode),
34	seq(choice("from", "to"), $.filename)
35	)
36	),
37
38	binary_change: ($) =>
39	iseq("Binary", "files", $.filename, "and", $.filename, "differ"),
40
41	index: ($) => iseq("index", $.commit, "..", $.commit, optional($.mode)),
42
43	similarity: ($) => iseq("similarity", "index", field("score", /\d+/), "%"),
44
45	file: ($) => iseq(field("kind", choice("---", "+++")), $.filename),
46
47	location: ($) => iseq("@@", $.linerange, $.linerange, "@@", ANYTHING),
48
49	addition: ($) => iseq("+", optional(ANYTHING)),
50
51	deletion: ($) => iseq("-", optional(ANYTHING)),
52
53	context: ($) => token(prec(-1, ANYTHING)),
54
55	linerange: ($) => /[-\+]\d+,\d+/,
56	filename: ($) => repeat1(/\S+/),
57	commit: ($) => /[a-f0-9]{7,40}/,
58	mode: ($) => /\d+/,
59	},
60	});
61
62	function iseq(start_token, ...tokens) {
63	return seq(token.immediate(start_token), ...tokens);
64	}