Some usability ideas around SkTHash.
- By default, use new SkGoodHash to hash keys, which is:
* for 4 byte values, use SkChecksum::Mix,
* for SkStrings, use SkChecksum::Murmur3 on the data,
* for other structs, shallow hash the struct with Murmur3.
- Expand SkChecksum::Murmur3 to support non-4-byte-aligned data.
- Add const foreach() methods.
- Have foreach() take a functor, which allows lambdas.
BUG=skia:
Review URL: https://codereview.chromium.org/1021033002
diff --git a/tests/HashTest.cpp b/tests/HashTest.cpp
index 623e597..5abf3db 100644
--- a/tests/HashTest.cpp
+++ b/tests/HashTest.cpp
@@ -3,12 +3,15 @@
#include "SkTHash.h"
#include "Test.h"
-namespace { uint32_t hash_int(const int& k) { return SkChecksum::Mix(k); } }
-
-static void set_negative_key(int key, double* d) { *d = -key; }
+// Tests use of const foreach(). map.count() is of course the better way to do this.
+static int count(const SkTHashMap<int, double>& map) {
+ int n = 0;
+ map.foreach([&n](int, double) { n++; });
+ return n;
+}
DEF_TEST(HashMap, r) {
- SkTHashMap<int, double, hash_int> map;
+ SkTHashMap<int, double> map;
map.set(3, 4.0);
REPORTER_ASSERT(r, map.count() == 1);
@@ -17,7 +20,9 @@
REPORTER_ASSERT(r, found);
REPORTER_ASSERT(r, *found == 4.0);
- map.foreach(set_negative_key);
+ map.foreach([](int key, double* d){ *d = -key; });
+ REPORTER_ASSERT(r, count(map) == 1);
+
found = map.find(3);
REPORTER_ASSERT(r, found);
REPORTER_ASSERT(r, *found == -3.0);
@@ -44,10 +49,8 @@
REPORTER_ASSERT(r, map.count() == 0);
}
-namespace { uint32_t hash_string(const SkString& s) { return SkToInt(s.size()); } }
-
DEF_TEST(HashSet, r) {
- SkTHashSet<SkString, hash_string> set;
+ SkTHashSet<SkString> set;
set.add(SkString("Hello"));
set.add(SkString("World"));