1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
module Gitlab
module Diff
class InlineDiff
attr_accessor :old_line, :new_line, :offset
def self.for_lines(lines)
local_edit_indexes = self.find_local_edits(lines)
inline_diffs = []
local_edit_indexes.each do |index|
old_index = index
new_index = index + 1
old_line = lines[old_index]
new_line = lines[new_index]
old_diffs, new_diffs = new(old_line, new_line, offset: 1).inline_diffs
inline_diffs[old_index] = old_diffs
inline_diffs[new_index] = new_diffs
end
inline_diffs
end
def initialize(old_line, new_line, offset: 0)
@old_line = old_line[offset..-1]
@new_line = new_line[offset..-1]
@offset = offset
end
def inline_diffs
# Skip inline diff if empty line was replaced with content
return if old_line == ""
lcp = longest_common_prefix(old_line, new_line)
lcs = longest_common_suffix(old_line[lcp..-1], new_line[lcp..-1])
lcp += offset
old_length = old_line.length + offset
new_length = new_line.length + offset
old_diff_range = lcp..(old_length - lcs - 1)
new_diff_range = lcp..(new_length - lcs - 1)
old_diffs = [old_diff_range] if old_diff_range.begin <= old_diff_range.end
new_diffs = [new_diff_range] if new_diff_range.begin <= new_diff_range.end
[old_diffs, new_diffs]
end
private
def self.find_local_edits(lines)
line_prefixes = lines.map { |line| line.match(/\A([+-])/) ? $1 : ' ' }
joined_line_prefixes = " #{line_prefixes.join} "
offset = 0
local_edit_indexes = []
while index = joined_line_prefixes.index(" -+ ", offset)
local_edit_indexes << index
offset = index + 1
end
local_edit_indexes
end
def longest_common_prefix(a, b)
max_length = [a.length, b.length].max
length = 0
(0..max_length - 1).each do |pos|
old_char = a[pos]
new_char = b[pos]
break if old_char != new_char
length += 1
end
length
end
def longest_common_suffix(a, b)
longest_common_prefix(a.reverse, b.reverse)
end
end
end
end
|
