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27
28#include <stdlib.h>
29
30#include "src/v8.h"
31
32#include "src/liveedit.h"
33#include "test/cctest/cctest.h"
34
35
36using namespace v8::internal;
37
38// Anonymous namespace.
39namespace {
40
41class StringCompareInput : public Comparator::Input {
42 public:
43  StringCompareInput(const char* s1, const char* s2) : s1_(s1), s2_(s2) {
44  }
45  int GetLength1() {
46    return StrLength(s1_);
47  }
48  int GetLength2() {
49    return StrLength(s2_);
50  }
51  bool Equals(int index1, int index2) {
52    return s1_[index1] == s2_[index2];
53  }
54
55 private:
56  const char* s1_;
57  const char* s2_;
58};
59
60
61class DiffChunkStruct : public ZoneObject {
62 public:
63  DiffChunkStruct(int pos1_param, int pos2_param,
64                  int len1_param, int len2_param)
65      : pos1(pos1_param), pos2(pos2_param),
66        len1(len1_param), len2(len2_param), next(NULL) {}
67  int pos1;
68  int pos2;
69  int len1;
70  int len2;
71  DiffChunkStruct* next;
72};
73
74
75class ListDiffOutputWriter : public Comparator::Output {
76 public:
77  explicit ListDiffOutputWriter(DiffChunkStruct** next_chunk_pointer,
78                                Zone* zone)
79      : next_chunk_pointer_(next_chunk_pointer), zone_(zone) {
80    (*next_chunk_pointer_) = NULL;
81  }
82  void AddChunk(int pos1, int pos2, int len1, int len2) {
83    current_chunk_ = new(zone_) DiffChunkStruct(pos1, pos2, len1, len2);
84    (*next_chunk_pointer_) = current_chunk_;
85    next_chunk_pointer_ = &current_chunk_->next;
86  }
87 private:
88  DiffChunkStruct** next_chunk_pointer_;
89  DiffChunkStruct* current_chunk_;
90  Zone* zone_;
91};
92
93
94void CompareStringsOneWay(const char* s1, const char* s2,
95                          int expected_diff_parameter = -1) {
96  StringCompareInput input(s1, s2);
97
98  Zone zone(CcTest::i_isolate());
99
100  DiffChunkStruct* first_chunk;
101  ListDiffOutputWriter writer(&first_chunk, &zone);
102
103  Comparator::CalculateDifference(&input, &writer);
104
105  int len1 = StrLength(s1);
106  int len2 = StrLength(s2);
107
108  int pos1 = 0;
109  int pos2 = 0;
110
111  int diff_parameter = 0;
112
113  for (DiffChunkStruct* chunk = first_chunk;
114      chunk != NULL;
115      chunk = chunk->next) {
116    int diff_pos1 = chunk->pos1;
117    int similar_part_length = diff_pos1 - pos1;
118    int diff_pos2 = pos2 + similar_part_length;
119
120    DCHECK_EQ(diff_pos2, chunk->pos2);
121
122    for (int j = 0; j < similar_part_length; j++) {
123      DCHECK(pos1 + j < len1);
124      DCHECK(pos2 + j < len2);
125      DCHECK_EQ(s1[pos1 + j], s2[pos2 + j]);
126    }
127    diff_parameter += chunk->len1 + chunk->len2;
128    pos1 = diff_pos1 + chunk->len1;
129    pos2 = diff_pos2 + chunk->len2;
130  }
131  {
132    // After last chunk.
133    int similar_part_length = len1 - pos1;
134    DCHECK_EQ(similar_part_length, len2 - pos2);
135    USE(len2);
136    for (int j = 0; j < similar_part_length; j++) {
137      DCHECK(pos1 + j < len1);
138      DCHECK(pos2 + j < len2);
139      DCHECK_EQ(s1[pos1 + j], s2[pos2 + j]);
140    }
141  }
142
143  if (expected_diff_parameter != -1) {
144    DCHECK_EQ(expected_diff_parameter, diff_parameter);
145  }
146}
147
148
149void CompareStrings(const char* s1, const char* s2,
150                    int expected_diff_parameter = -1) {
151  CompareStringsOneWay(s1, s2, expected_diff_parameter);
152  CompareStringsOneWay(s2, s1, expected_diff_parameter);
153}
154
155}  // Anonymous namespace.
156
157
158// --- T h e   A c t u a l   T e s t s
159
160TEST(LiveEditDiffer) {
161  CompareStrings("zz1zzz12zz123zzz", "zzzzzzzzzz", 6);
162  CompareStrings("zz1zzz12zz123zzz", "zz0zzz0zz0zzz", 9);
163  CompareStrings("123456789", "987654321", 16);
164  CompareStrings("zzz", "yyy", 6);
165  CompareStrings("zzz", "zzz12", 2);
166  CompareStrings("zzz", "21zzz", 2);
167  CompareStrings("cat", "cut", 2);
168  CompareStrings("ct", "cut", 1);
169  CompareStrings("cat", "ct", 1);
170  CompareStrings("cat", "cat", 0);
171  CompareStrings("", "", 0);
172  CompareStrings("cat", "", 3);
173  CompareStrings("a cat", "a capybara", 7);
174  CompareStrings("abbabababababaaabbabababababbabbbbbbbababa",
175                 "bbbbabababbbabababbbabababababbabbababa");
176}
177