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
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
|
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package flate
import (
"bytes"
"strings"
"testing"
)
func TestDictDecoder(t *testing.T) {
const (
abc = "ABC\n"
fox = "The quick brown fox jumped over the lazy dog!\n"
poem = "The Road Not Taken\nRobert Frost\n" +
"\n" +
"Two roads diverged in a yellow wood,\n" +
"And sorry I could not travel both\n" +
"And be one traveler, long I stood\n" +
"And looked down one as far as I could\n" +
"To where it bent in the undergrowth;\n" +
"\n" +
"Then took the other, as just as fair,\n" +
"And having perhaps the better claim,\n" +
"Because it was grassy and wanted wear;\n" +
"Though as for that the passing there\n" +
"Had worn them really about the same,\n" +
"\n" +
"And both that morning equally lay\n" +
"In leaves no step had trodden black.\n" +
"Oh, I kept the first for another day!\n" +
"Yet knowing how way leads on to way,\n" +
"I doubted if I should ever come back.\n" +
"\n" +
"I shall be telling this with a sigh\n" +
"Somewhere ages and ages hence:\n" +
"Two roads diverged in a wood, and I-\n" +
"I took the one less traveled by,\n" +
"And that has made all the difference.\n"
)
poemRefs := []struct {
dist int // Backward distance (0 if this is an insertion)
length int // Length of copy or insertion
}{
{0, 38},
{33, 3},
{0, 48},
{79, 3},
{0, 11},
{34, 5},
{0, 6},
{23, 7},
{0, 8},
{50, 3},
{0, 2},
{69, 3},
{34, 5},
{0, 4},
{97, 3},
{0, 4},
{43, 5},
{0, 6},
{7, 4},
{88, 7},
{0, 12},
{80, 3},
{0, 2},
{141, 4},
{0, 1},
{196, 3},
{0, 3},
{157, 3},
{0, 6},
{181, 3},
{0, 2},
{23, 3},
{77, 3},
{28, 5},
{128, 3},
{110, 4},
{70, 3},
{0, 4},
{85, 6},
{0, 2},
{182, 6},
{0, 4},
{133, 3},
{0, 7},
{47, 5},
{0, 20},
{112, 5},
{0, 1},
{58, 3},
{0, 8},
{59, 3},
{0, 4},
{173, 3},
{0, 5},
{114, 3},
{0, 4},
{92, 5},
{0, 2},
{71, 3},
{0, 2},
{76, 5},
{0, 1},
{46, 3},
{96, 4},
{130, 4},
{0, 3},
{360, 3},
{0, 3},
{178, 5},
{0, 7},
{75, 3},
{0, 3},
{45, 6},
{0, 6},
{299, 6},
{180, 3},
{70, 6},
{0, 1},
{48, 3},
{66, 4},
{0, 3},
{47, 5},
{0, 9},
{325, 3},
{0, 1},
{359, 3},
{318, 3},
{0, 2},
{199, 3},
{0, 1},
{344, 3},
{0, 3},
{248, 3},
{0, 10},
{310, 3},
{0, 3},
{93, 6},
{0, 3},
{252, 3},
{157, 4},
{0, 2},
{273, 5},
{0, 14},
{99, 4},
{0, 1},
{464, 4},
{0, 2},
{92, 4},
{495, 3},
{0, 1},
{322, 4},
{16, 4},
{0, 3},
{402, 3},
{0, 2},
{237, 4},
{0, 2},
{432, 4},
{0, 1},
{483, 5},
{0, 2},
{294, 4},
{0, 2},
{306, 3},
{113, 5},
{0, 1},
{26, 4},
{164, 3},
{488, 4},
{0, 1},
{542, 3},
{248, 6},
{0, 5},
{205, 3},
{0, 8},
{48, 3},
{449, 6},
{0, 2},
{192, 3},
{328, 4},
{9, 5},
{433, 3},
{0, 3},
{622, 25},
{615, 5},
{46, 5},
{0, 2},
{104, 3},
{475, 10},
{549, 3},
{0, 4},
{597, 8},
{314, 3},
{0, 1},
{473, 6},
{317, 5},
{0, 1},
{400, 3},
{0, 3},
{109, 3},
{151, 3},
{48, 4},
{0, 4},
{125, 3},
{108, 3},
{0, 2},
}
var got, want bytes.Buffer
var dd dictDecoder
dd.init(1<<11, nil)
writeCopy := func(dist, length int) {
for length > 0 {
cnt := dd.tryWriteCopy(dist, length)
if cnt == 0 {
cnt = dd.writeCopy(dist, length)
}
length -= cnt
if dd.availWrite() == 0 {
got.Write(dd.readFlush())
}
}
}
writeString := func(str string) {
for len(str) > 0 {
cnt := copy(dd.writeSlice(), str)
str = str[cnt:]
dd.writeMark(cnt)
if dd.availWrite() == 0 {
got.Write(dd.readFlush())
}
}
}
writeString(".")
want.WriteByte('.')
str := poem
for _, ref := range poemRefs {
if ref.dist == 0 {
writeString(str[:ref.length])
} else {
writeCopy(ref.dist, ref.length)
}
str = str[ref.length:]
}
want.WriteString(poem)
writeCopy(dd.histSize(), 33)
want.Write(want.Bytes()[:33])
writeString(abc)
writeCopy(len(abc), 59*len(abc))
want.WriteString(strings.Repeat(abc, 60))
writeString(fox)
writeCopy(len(fox), 9*len(fox))
want.WriteString(strings.Repeat(fox, 10))
writeString(".")
writeCopy(1, 9)
want.WriteString(strings.Repeat(".", 10))
writeString(strings.ToUpper(poem))
writeCopy(len(poem), 7*len(poem))
want.WriteString(strings.Repeat(strings.ToUpper(poem), 8))
writeCopy(dd.histSize(), 10)
want.Write(want.Bytes()[want.Len()-dd.histSize():][:10])
got.Write(dd.readFlush())
if got.String() != want.String() {
t.Errorf("final string mismatch:\ngot %q\nwant %q", got.String(), want.String())
}
}
|
