AK: Define HashMap::take to find and remove a value from the map

This commit is contained in:
Timothy Flynn 2023-02-02 10:55:50 -05:00 committed by Linus Groh
parent f31bd190b0
commit 2af7447dfd
2 changed files with 57 additions and 0 deletions

View file

@ -199,6 +199,31 @@ public:
m_table.remove(it);
}
Optional<V> take(K const& key)
{
if (auto it = find(key); it != end()) {
auto value = move(it->value);
m_table.remove(it);
return value;
}
return {};
}
template<Concepts::HashCompatible<K> Key>
requires(IsSame<KeyTraits, Traits<K>>) Optional<V> take(Key const& key)
{
if (auto it = find(key); it != end()) {
auto value = move(it->value);
m_table.remove(it);
return value;
}
return {};
}
V& ensure(K const& key)
{
auto it = find(key);

View file

@ -9,6 +9,7 @@
#include <AK/DeprecatedString.h>
#include <AK/HashMap.h>
#include <AK/OwnPtr.h>
#include <AK/String.h>
TEST_CASE(construct)
{
@ -219,3 +220,34 @@ TEST_CASE(in_place_rehashing_ordered_loop_bug)
map.set("yt.innertube::nextId", "");
VERIFY(map.keys().size() == 2);
}
TEST_CASE(take)
{
HashMap<String, int> map;
EXPECT(!map.take("foo"sv).has_value());
EXPECT(!map.take("bar"sv).has_value());
EXPECT(!map.take(String::from_utf8_short_string("baz"sv)).has_value());
map.set(String::from_utf8_short_string("foo"sv), 1);
map.set(String::from_utf8_short_string("bar"sv), 2);
map.set(String::from_utf8_short_string("baz"sv), 3);
auto foo = map.take("foo"sv);
EXPECT_EQ(foo, 1);
foo = map.take("foo"sv);
EXPECT(!foo.has_value());
auto bar = map.take("bar"sv);
EXPECT_EQ(bar, 2);
bar = map.take("bar"sv);
EXPECT(!bar.has_value());
auto baz = map.take(String::from_utf8_short_string("baz"sv));
EXPECT_EQ(baz, 3);
baz = map.take(String::from_utf8_short_string("baz"sv));
EXPECT(!baz.has_value());
}