1 /*
2  * Copyright 2013 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "SkTDynamicHash.h"
9 #include "Test.h"
10 
11 namespace {
12 
13 struct Entry {
14     int key;
15     double value;
16 
GetKey__anon776810e40111::Entry17     static const int& GetKey(const Entry& entry) { return entry.key; }
Hash__anon776810e40111::Entry18     static uint32_t Hash(const int& key) { return key; }
19 };
20 
21 
22 class Hash : public SkTDynamicHash<Entry, int> {
23 public:
Hash()24     Hash() : INHERITED() {}
25 
26     // Promote protected methods to public for this test.
capacity() const27     int capacity() const { return this->INHERITED::capacity(); }
countCollisions(const int & key) const28     int countCollisions(const int& key) const { return this->INHERITED::countCollisions(key); }
29 
30 private:
31     typedef SkTDynamicHash<Entry, int> INHERITED;
32 };
33 
34 }  // namespace
35 
36 #define ASSERT(x) REPORTER_ASSERT(reporter, x)
37 
DEF_TEST(DynamicHash_growth,reporter)38 DEF_TEST(DynamicHash_growth, reporter) {
39     Entry a = { 1, 2.0 };
40     Entry b = { 2, 3.0 };
41     Entry c = { 3, 4.0 };
42     Entry d = { 4, 5.0 };
43     Entry e = { 5, 6.0 };
44 
45     Hash hash;
46     ASSERT(hash.capacity() == 0);
47 
48     hash.add(&a);
49     ASSERT(hash.capacity() == 4);
50 
51     hash.add(&b);
52     ASSERT(hash.capacity() == 4);
53 
54     hash.add(&c);
55     ASSERT(hash.capacity() == 4);
56 
57     hash.add(&d);
58     ASSERT(hash.capacity() == 8);
59 
60     hash.add(&e);
61     ASSERT(hash.capacity() == 8);
62 
63     ASSERT(hash.count() == 5);
64 }
65 
DEF_TEST(DynamicHash_add,reporter)66 DEF_TEST(DynamicHash_add, reporter) {
67     Hash hash;
68     Entry a = { 1, 2.0 };
69     Entry b = { 2, 3.0 };
70 
71     ASSERT(hash.count() == 0);
72     hash.add(&a);
73     ASSERT(hash.count() == 1);
74     hash.add(&b);
75     ASSERT(hash.count() == 2);
76 }
77 
DEF_TEST(DynamicHash_lookup,reporter)78 DEF_TEST(DynamicHash_lookup, reporter) {
79     Hash hash;
80 
81     // These collide.
82     Entry a = { 1, 2.0 };
83     Entry b = { 5, 3.0 };
84 
85     // Before we insert anything, nothing can collide.
86     ASSERT(hash.countCollisions(1) == 0);
87     ASSERT(hash.countCollisions(5) == 0);
88     ASSERT(hash.countCollisions(9) == 0);
89 
90     // First is easy.
91     hash.add(&a);
92     ASSERT(hash.countCollisions(1) == 0);
93     ASSERT(hash.countCollisions(5) == 1);
94     ASSERT(hash.countCollisions(9) == 1);
95 
96     // Second is one step away.
97     hash.add(&b);
98     ASSERT(hash.countCollisions(1) == 0);
99     ASSERT(hash.countCollisions(5) == 1);
100     ASSERT(hash.countCollisions(9) == 2);
101 
102     // We can find our data right?
103     ASSERT(hash.find(1) != nullptr);
104     ASSERT(hash.find(1)->value == 2.0);
105     ASSERT(hash.find(5) != nullptr);
106     ASSERT(hash.find(5)->value == 3.0);
107 
108     // These aren't in the hash.
109     ASSERT(hash.find(2) == nullptr);
110     ASSERT(hash.find(9) == nullptr);
111 }
112 
DEF_TEST(DynamicHash_remove,reporter)113 DEF_TEST(DynamicHash_remove, reporter) {
114     Hash hash;
115 
116     // These collide.
117     Entry a = { 1, 2.0 };
118     Entry b = { 5, 3.0 };
119     Entry c = { 9, 4.0 };
120 
121     hash.add(&a);
122     hash.add(&b);
123     hash.remove(1);
124     // a should be marked deleted, and b should still be findable.
125 
126     ASSERT(hash.find(1) == nullptr);
127     ASSERT(hash.find(5) != nullptr);
128     ASSERT(hash.find(5)->value == 3.0);
129 
130     // This will go in the same slot as 'a' did before.
131     ASSERT(hash.countCollisions(9) == 0);
132     hash.add(&c);
133     ASSERT(hash.find(9) != nullptr);
134     ASSERT(hash.find(9)->value == 4.0);
135     ASSERT(hash.find(5) != nullptr);
136     ASSERT(hash.find(5)->value == 3.0);
137 }
138 
TestIter(skiatest::Reporter * reporter)139 template<typename T> static void TestIter(skiatest::Reporter* reporter) {
140     Hash hash;
141 
142     int count = 0;
143     // this should fall out of loop immediately
144     for (T iter(&hash); !iter.done(); ++iter) {
145         ++count;
146     }
147     ASSERT(0 == count);
148 
149     // These collide.
150     Entry a = { 1, 2.0 };
151     Entry b = { 5, 3.0 };
152     Entry c = { 9, 4.0 };
153 
154     hash.add(&a);
155     hash.add(&b);
156     hash.add(&c);
157 
158     // should see all 3 unique keys when iterating over hash
159     count = 0;
160     int keys[3] = {0, 0, 0};
161     for (T iter(&hash); !iter.done(); ++iter) {
162         int key = (*iter).key;
163         keys[count] = key;
164         ASSERT(hash.find(key) != nullptr);
165         ++count;
166     }
167     ASSERT(3 == count);
168     ASSERT(keys[0] != keys[1]);
169     ASSERT(keys[0] != keys[2]);
170     ASSERT(keys[1] != keys[2]);
171 
172     // should see 2 unique keys when iterating over hash that aren't 1
173     hash.remove(1);
174     count = 0;
175     memset(keys, 0, sizeof(keys));
176     for (T iter(&hash); !iter.done(); ++iter) {
177         int key = (*iter).key;
178         keys[count] = key;
179         ASSERT(key != 1);
180         ASSERT(hash.find(key) != nullptr);
181         ++count;
182     }
183     ASSERT(2 == count);
184     ASSERT(keys[0] != keys[1]);
185 }
186 
DEF_TEST(DynamicHash_iterator,reporter)187 DEF_TEST(DynamicHash_iterator, reporter) {
188     TestIter<Hash::Iter>(reporter);
189     TestIter<Hash::ConstIter>(reporter);
190 }
191 
TestResetOrRewind(skiatest::Reporter * reporter,bool testReset)192 static void TestResetOrRewind(skiatest::Reporter* reporter, bool testReset) {
193     Hash hash;
194     Entry a = { 1, 2.0 };
195     Entry b = { 2, 3.0 };
196 
197     ASSERT(hash.capacity() == 0);
198     hash.add(&a);
199     hash.add(&b);
200     ASSERT(hash.count() == 2);
201     ASSERT(hash.capacity() == 4);
202 
203     if (testReset) {
204         hash.reset();
205         ASSERT(hash.capacity() == 0);
206     } else {
207         hash.rewind();
208         ASSERT(hash.capacity() == 4);
209     }
210     ASSERT(hash.count() == 0);
211 
212     // make sure things still work
213     hash.add(&a);
214     hash.add(&b);
215     ASSERT(hash.count() == 2);
216     ASSERT(hash.capacity() == 4);
217 
218     ASSERT(hash.find(1) != nullptr);
219     ASSERT(hash.find(2) != nullptr);
220 }
221 
DEF_TEST(DynamicHash_reset,reporter)222 DEF_TEST(DynamicHash_reset, reporter) {
223     TestResetOrRewind(reporter, true);
224 }
225 
DEF_TEST(DynamicHash_rewind,reporter)226 DEF_TEST(DynamicHash_rewind, reporter) {
227     TestResetOrRewind(reporter, false);
228 }
229