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
|
# gzip-like LZSS compressor
# Copyright (C) 2018 Pacien TRAN-GIRARD
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
import unittest, sequtils
import lzss/matchring, lzss/matchtable, lzss/lzssnode, lzss/lzssencoder
suite "lzssencoder":
test "commonPrefixLength":
check commonPrefixLength([], [], 10) == 0
check commonPrefixLength([1'u8, 2], [1'u8, 2, 3], 10) == 2
check commonPrefixLength([1'u8, 2], [1'u8, 2, 3], 10) == 2
check commonPrefixLength([1'u8, 2, 3], [1'u8, 2, 4], 10) == 2
check commonPrefixLength([1'u8, 2, 3, 4], [1'u8, 2, 3, 4], 3) == 3
test "longestPrefix":
let buffer = [
0'u8, 1, 2, 9,
0, 1, 2, 3,
0, 1, 2,
0, 1, 2, 3, 4]
var candidatePos = [0, 4, 8]
var matchRing = initMatchRing()
for pos in candidatePos: matchRing.addMatch(pos)
let result = longestPrefix(matchRing, buffer.toOpenArray(0, 10), buffer.toOpenArray(11, buffer.len - 1))
check result.pos == 4
check result.length == 4
test "addGroups":
var matchTable = initMatchTable()
let buffer = toSeq(0'u8..10'u8)
matchTable.addGroups(buffer, 0, 1)
matchTable.addGroups(buffer, 2, 9)
check toSeq(matchTable.candidates([1'u8, 2, 3]).items).len == 0
check toSeq(matchTable.candidates([7'u8, 8, 9]).items).len == 0
check toSeq(matchTable.candidates([2'u8, 3, 4]).items) == [2]
check toSeq(matchTable.candidates([4'u8, 5, 6]).items) == [4]
check toSeq(matchTable.candidates([6'u8, 7, 8]).items) == [6]
test "lzssEncode":
let buffer = [0'u8, 1, 2, 3, 4, 5, 0, 1, 2, 3, 0, 1, 4, 5, 0, 5, 5, 0, 5, 5]
check lzssEncode(buffer) == [
lzssCharacter(0), lzssCharacter(1), lzssCharacter(2),
lzssCharacter(3), lzssCharacter(4), lzssCharacter(5),
lzssReference(4, 6), lzssCharacter(0), lzssCharacter(1),
lzssReference(3, 8), lzssCharacter(5),
lzssReference(3, 3), lzssCharacter(5)]
|