From 969d159bd712c8d974f5122492a9615e66c0be9c Mon Sep 17 00:00:00 2001 From: Matthew Wild Date: Thu, 17 Mar 2016 19:07:40 +0000 Subject: [PATCH] util.cache: Add head() and tail() methods (and tests) --- tests/test_util_cache.lua | 27 ++++++++++++++++++++++++++- util/cache.lua | 12 ++++++++++++ 2 files changed, 38 insertions(+), 1 deletion(-) diff --git a/tests/test_util_cache.lua b/tests/test_util_cache.lua index 72cb5a85..ecdc2dc0 100644 --- a/tests/test_util_cache.lua +++ b/tests/test_util_cache.lua @@ -1,21 +1,44 @@ - function new(new) local c = new(5); + local function expect_kv(key, value, actual_key, actual_value) + assert_equal(key, actual_key, "key incorrect"); + assert_equal(value, actual_value, "value incorrect"); + end + + expect_kv(nil, nil, c:head()); + expect_kv(nil, nil, c:tail()); + assert_equal(c:count(), 0); c:set("one", 1) assert_equal(c:count(), 1); + expect_kv("one", 1, c:head()); + expect_kv("one", 1, c:tail()); + c:set("two", 2) + expect_kv("two", 2, c:head()); + expect_kv("one", 1, c:tail()); + c:set("three", 3) + expect_kv("three", 3, c:head()); + expect_kv("one", 1, c:tail()); + c:set("four", 4) c:set("five", 5); assert_equal(c:count(), 5); + expect_kv("five", 5, c:head()); + expect_kv("one", 1, c:tail()); c:set("foo", nil); assert_equal(c:count(), 5); + expect_kv("five", 5, c:head()); + expect_kv("one", 1, c:tail()); assert_equal(c:get("one"), 1); + expect_kv("five", 5, c:head()); + expect_kv("one", 1, c:tail()); + assert_equal(c:get("two"), 2); assert_equal(c:get("three"), 3); assert_equal(c:get("four"), 4); @@ -26,6 +49,8 @@ function new(new) c:set("six", 6); assert_equal(c:count(), 5); + expect_kv("six", 6, c:head()); + expect_kv("two", 2, c:tail()); assert_equal(c:get("one"), nil); assert_equal(c:get("two"), 2); diff --git a/util/cache.lua b/util/cache.lua index d3639b3f..e53bf4bf 100644 --- a/util/cache.lua +++ b/util/cache.lua @@ -92,6 +92,18 @@ function cache_methods:count() return self._count; end +function cache_methods:head() + local head = self._head; + if not head then return nil, nil; end + return head.key, head.value; +end + +function cache_methods:tail() + local tail = self._tail; + if not tail then return nil, nil; end + return tail.key, tail.value; +end + local function new(size, on_evict) size = assert(tonumber(size), "cache size must be a number"); size = math.floor(size); -- 2.30.2