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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 
36 using namespace v8::internal;
37 
38 // Anonymous namespace.
39 namespace {
40 
41 class StringCompareInput : public Comparator::Input {
42  public:
StringCompareInput(const char * s1,const char * s2)43   StringCompareInput(const char* s1, const char* s2) : s1_(s1), s2_(s2) {
44   }
GetLength1()45   int GetLength1() {
46     return StrLength(s1_);
47   }
GetLength2()48   int GetLength2() {
49     return StrLength(s2_);
50   }
Equals(int index1,int index2)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 
61 class DiffChunkStruct : public ZoneObject {
62  public:
DiffChunkStruct(int pos1_param,int pos2_param,int len1_param,int len2_param)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 
75 class ListDiffOutputWriter : public Comparator::Output {
76  public:
ListDiffOutputWriter(DiffChunkStruct ** next_chunk_pointer,Zone * zone)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   }
AddChunk(int pos1,int pos2,int len1,int len2)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 
CompareStringsOneWay(const char * s1,const char * s2,int expected_diff_parameter=-1)94 void 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 
CompareStrings(const char * s1,const char * s2,int expected_diff_parameter=-1)149 void 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 
TEST(LiveEditDiffer)160 TEST(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