File

spec/util_cache_spec.lua @ 13186:affaf6d08d26

util.datamanager: Pad list writes to avoid crossing block boundaries By padding items so that they do not cross block boundaries, it becomes eaiser to delete whole blocks with fallocate() without cutting items in half, improving efficiency of such operations. Since list stores are used for message archives, where the most common deletion operation would be of the oldest entires, at the top of the file. With this, all blocks that contain items to be removed could be deleted without needing to read, delete and write out the whole file.
author Kim Alvefur <zash@zash.se>
date Wed, 07 Jun 2023 00:39:30 +0200
parent 13175:bbdaa770b955
line wrap: on
line source


local cache = require "util.cache";

describe("util.cache", function()
	describe("#new()", function()
		it("should work", function()
			do
				local c = cache.new(1);
				assert.is_not_nil(c);

				assert.has_error(function ()
					cache.new(0);
				end);
				assert.has_error(function ()
					cache.new(-1);
				end);
				assert.has_error(function ()
					cache.new("foo");
				end);
			end

			local c = cache.new(5);

			local function expect_kv(key, value, actual_key, actual_value)
				assert.are.equal(key, actual_key, "key incorrect");
				assert.are.equal(value, actual_value, "value incorrect");
			end

			expect_kv(nil, nil, c:head());
			expect_kv(nil, nil, c:tail());

			assert.are.equal(c:count(), 0);

			c:set("one", 1)
			assert.are.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.are.equal(c:count(), 5);
			expect_kv("five", 5, c:head());
			expect_kv("one", 1, c:tail());

			c:set("foo", nil);
			assert.are.equal(c:count(), 5);
			expect_kv("five", 5, c:head());
			expect_kv("one", 1, c:tail());

			assert.are.equal(c:get("one"), 1);
			expect_kv("five", 5, c:head());
			expect_kv("one", 1, c:tail());

			assert.are.equal(c:get("two"), 2);
			assert.are.equal(c:get("three"), 3);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), 5);

			assert.are.equal(c:get("foo"), nil);
			assert.are.equal(c:get("bar"), nil);

			c:set("six", 6);
			assert.are.equal(c:count(), 5);
			expect_kv("six", 6, c:head());
			expect_kv("two", 2, c:tail());

			assert.are.equal(c:get("one"), nil);
			assert.are.equal(c:get("two"), 2);
			assert.are.equal(c:get("three"), 3);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), 5);
			assert.are.equal(c:get("six"), 6);

			c:set("three", nil);
			assert.are.equal(c:count(), 4);

			assert.are.equal(c:get("one"), nil);
			assert.are.equal(c:get("two"), 2);
			assert.are.equal(c:get("three"), nil);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), 5);
			assert.are.equal(c:get("six"), 6);

			c:set("seven", 7);
			assert.are.equal(c:count(), 5);

			assert.are.equal(c:get("one"), nil);
			assert.are.equal(c:get("two"), 2);
			assert.are.equal(c:get("three"), nil);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), 5);
			assert.are.equal(c:get("six"), 6);
			assert.are.equal(c:get("seven"), 7);

			c:set("eight", 8);
			assert.are.equal(c:count(), 5);

			assert.are.equal(c:get("one"), nil);
			assert.are.equal(c:get("two"), nil);
			assert.are.equal(c:get("three"), nil);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), 5);
			assert.are.equal(c:get("six"), 6);
			assert.are.equal(c:get("seven"), 7);
			assert.are.equal(c:get("eight"), 8);

			c:set("four", 4);
			assert.are.equal(c:count(), 5);

			assert.are.equal(c:get("one"), nil);
			assert.are.equal(c:get("two"), nil);
			assert.are.equal(c:get("three"), nil);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), 5);
			assert.are.equal(c:get("six"), 6);
			assert.are.equal(c:get("seven"), 7);
			assert.are.equal(c:get("eight"), 8);

			c:set("nine", 9);
			assert.are.equal(c:count(), 5);

			assert.are.equal(c:get("one"), nil);
			assert.are.equal(c:get("two"), nil);
			assert.are.equal(c:get("three"), nil);
			assert.are.equal(c:get("four"), 4);
			assert.are.equal(c:get("five"), nil);
			assert.are.equal(c:get("six"), 6);
			assert.are.equal(c:get("seven"), 7);
			assert.are.equal(c:get("eight"), 8);
			assert.are.equal(c:get("nine"), 9);

			do
				local keys = { "nine", "four", "eight", "seven", "six" };
				local values = { 9, 4, 8, 7, 6 };
				local i = 0;
				for k, v in c:items() do
					i = i + 1;
					assert.are.equal(k, keys[i]);
					assert.are.equal(v, values[i]);
				end
				assert.are.equal(i, 5);

				c:set("four", "2+2");
				assert.are.equal(c:count(), 5);

				assert.are.equal(c:get("one"), nil);
				assert.are.equal(c:get("two"), nil);
				assert.are.equal(c:get("three"), nil);
				assert.are.equal(c:get("four"), "2+2");
				assert.are.equal(c:get("five"), nil);
				assert.are.equal(c:get("six"), 6);
				assert.are.equal(c:get("seven"), 7);
				assert.are.equal(c:get("eight"), 8);
				assert.are.equal(c:get("nine"), 9);
			end

			do
				local keys = { "four", "nine", "eight", "seven", "six" };
				local values = { "2+2", 9, 8, 7, 6 };
				local i = 0;
				for k, v in c:items() do
					i = i + 1;
					assert.are.equal(k, keys[i]);
					assert.are.equal(v, values[i]);
				end
				assert.are.equal(i, 5);

				c:set("foo", nil);
				assert.are.equal(c:count(), 5);

				assert.are.equal(c:get("one"), nil);
				assert.are.equal(c:get("two"), nil);
				assert.are.equal(c:get("three"), nil);
				assert.are.equal(c:get("four"), "2+2");
				assert.are.equal(c:get("five"), nil);
				assert.are.equal(c:get("six"), 6);
				assert.are.equal(c:get("seven"), 7);
				assert.are.equal(c:get("eight"), 8);
				assert.are.equal(c:get("nine"), 9);
			end

			do
				local keys = { "four", "nine", "eight", "seven", "six" };
				local values = { "2+2", 9, 8, 7, 6 };
				local i = 0;
				for k, v in c:items() do
					i = i + 1;
					assert.are.equal(k, keys[i]);
					assert.are.equal(v, values[i]);
				end
				assert.are.equal(i, 5);

				c:set("four", nil);

				assert.are.equal(c:get("one"), nil);
				assert.are.equal(c:get("two"), nil);
				assert.are.equal(c:get("three"), nil);
				assert.are.equal(c:get("four"), nil);
				assert.are.equal(c:get("five"), nil);
				assert.are.equal(c:get("six"), 6);
				assert.are.equal(c:get("seven"), 7);
				assert.are.equal(c:get("eight"), 8);
				assert.are.equal(c:get("nine"), 9);
			end

			do
				local keys = { "nine", "eight", "seven", "six" };
				local values = { 9, 8, 7, 6 };
				local i = 0;
				for k, v in c:items() do
					i = i + 1;
					assert.are.equal(k, keys[i]);
					assert.are.equal(v, values[i]);
				end
				assert.are.equal(i, 4);
			end

			do
				local evicted_key, evicted_value;
				local c2 = cache.new(3, function (_key, _value)
					evicted_key, evicted_value = _key, _value;
				end);
				local function set(k, v, should_evict_key, should_evict_value)
					evicted_key, evicted_value = nil, nil;
					c2:set(k, v);
					assert.are.equal(evicted_key, should_evict_key);
					assert.are.equal(evicted_value, should_evict_value);
				end
				set("a", 1)
				set("a", 1)
				set("a", 1)
				set("a", 1)
				set("a", 1)

				set("b", 2)
				set("c", 3)
				set("b", 2)
				set("d", 4, "a", 1)
				set("e", 5, "c", 3)
			end

			do
				local evicted_key, evicted_value;
				local c3 = cache.new(1, function (_key, _value)
					evicted_key, evicted_value = _key, _value;
					if _key == "a" then
						-- Sanity check for what we're evicting
						assert.are.equal(_key, "a");
						assert.are.equal(_value, 1);
						-- We're going to block eviction of this key/value, so set to nil...
						evicted_key, evicted_value = nil, nil;
						-- Returning false to block eviction
						return false
					end
				end);
				local function set(k, v, should_evict_key, should_evict_value)
					evicted_key, evicted_value = nil, nil;
					local ret = c3:set(k, v);
					assert.are.equal(evicted_key, should_evict_key);
					assert.are.equal(evicted_value, should_evict_value);
					return ret;
				end
				set("a", 1)
				set("a", 1)
				set("a", 1)
				set("a", 1)
				set("a", 1)

				-- Our on_evict prevents "a" from being evicted, causing this to fail...
				assert.are.equal(set("b", 2), false, "Failed to prevent eviction, or signal result");

				expect_kv("a", 1, c3:head());
				expect_kv("a", 1, c3:tail());

				-- Check the final state is what we expect
				assert.are.equal(c3:get("a"), 1);
				assert.are.equal(c3:get("b"), nil);
				assert.are.equal(c3:count(), 1);
			end


			local c4 = cache.new(3, false);

			assert.are.equal(c4:set("a", 1), true);
			assert.are.equal(c4:set("a", 1), true);
			assert.are.equal(c4:set("a", 1), true);
			assert.are.equal(c4:set("a", 1), true);
			assert.are.equal(c4:set("b", 2), true);
			assert.are.equal(c4:set("c", 3), true);
			assert.are.equal(c4:set("d", 4), false);
			assert.are.equal(c4:set("d", 4), false);
			assert.are.equal(c4:set("d", 4), false);

			expect_kv("c", 3, c4:head());
			expect_kv("a", 1, c4:tail());

			local c5 = cache.new(3, function (k, v) --luacheck: ignore 212/v
				if k == "a" then
					return nil;
				elseif k == "b" then
					return true;
				end
				return false;
			end);

			assert.are.equal(c5:set("a", 1), true);
			assert.are.equal(c5:set("a", 1), true);
			assert.are.equal(c5:set("a", 1), true);
			assert.are.equal(c5:set("a", 1), true);
			assert.are.equal(c5:set("b", 2), true);
			assert.are.equal(c5:set("c", 3), true);
			assert.are.equal(c5:set("d", 4), true); -- "a" evicted (cb returned nil)
			assert.are.equal(c5:set("d", 4), true); -- nop
			assert.are.equal(c5:set("d", 4), true); -- nop
			assert.are.equal(c5:set("e", 5), true); -- "b" evicted (cb returned true)
			assert.are.equal(c5:set("f", 6), false); -- "c" won't evict (cb returned false)

			expect_kv("e", 5, c5:head());
			expect_kv("c", 3, c5:tail());

		end);

		it(":table works", function ()
			local t = cache.new(3):table();
			assert.is.table(t);
			t["a"] = "1";
			assert.are.equal(t["a"], "1");
			t["b"] = "2";
			assert.are.equal(t["b"], "2");
			t["c"] = "3";
			assert.are.equal(t["c"], "3");
			t["d"] = "4";
			assert.are.equal(t["d"], "4");
			assert.are.equal(t["a"], nil);

				local i = spy.new(function () end);
				for k, v in pairs(t) do
					i(k,v)
				end
				assert.spy(i).was_called();
				assert.spy(i).was_called_with("b", "2");
				assert.spy(i).was_called_with("c", "3");
				assert.spy(i).was_called_with("d", "4");
		end);

		local function vs(t)
			local vs_ = {};
			for v in t:values() do
				vs_[#vs_+1] = v;
			end
			return vs_;
		end

		it(":values works", function ()
			local t = cache.new(3);
			t:set("k1", "v1");
			t:set("k2", "v2");
			assert.same({"v2", "v1"}, vs(t));
			t:set("k3", "v3");
			assert.same({"v3", "v2", "v1"}, vs(t));
			t:set("k4", "v4");
			assert.same({"v4", "v3", "v2"}, vs(t));
		end);

		it(":resize works", function ()
			local c = cache.new(5);
			for i = 1, 5 do
				c:set(("k%d"):format(i), ("v%d"):format(i));
			end
			assert.same({"v5", "v4", "v3", "v2", "v1"}, vs(c));
			assert.has_error(function ()
				c:resize(-1);
			end);
			assert.has_error(function ()
				c:resize(0);
			end);
			assert.has_error(function ()
				c:resize("foo");
			end);
			c:resize(3);
			assert.same({"v5", "v4", "v3"}, vs(c));
		end);

		it("eviction stuff", function ()
			local c = cache.new(4, function(_k,_v,c)
				if c.size < 10 then
					c:resize(c.size*2);
				end
			end)
			for i = 1,20 do
				c:set(i,i)
			end
			assert.equal(16, c.size);
			assert.is_nil(c:get(1))
			assert.is_nil(c:get(4))
			assert.equal(5, c:get(5))
			assert.equal(20, c:get(20))
			c:resize(4)
			assert.equal(20, c:get(20))
			assert.equal(17, c:get(17))
			assert.is_nil(c:get(10))
		end)
	end);
end);