File

spec/util_queue_spec.lua @ 10571:cfeb0077c9e9

net.server_epoll: Avoid concatenating buffer with single item Saves creating a string that'll be identical to buffer[1] anyways, as well as a C function call. Depending on Lua version and length of the string, this could be reusing an interned string, but a longer one would probably be duplicated for no reason. Having exactly one item in the buffer seems like it would be fairly common, but I have not done an extensive study. If opportunistic writes are enabled then it will be even more likely. This special case could be optimized like this in table.concat but it does not look like it is.
author Kim Alvefur <zash@zash.se>
date Sat, 28 Dec 2019 06:18:58 +0100 (2019-12-28)
parent 9901:c8b75239846c
child 13558:56e112b890ea
line wrap: on
line source

local queue = require "util.queue";

describe("util.queue", function()
	describe("#new()", function()
		it("should work", function()

			do
				local q = queue.new(10);

				assert.are.equal(q.size, 10);
				assert.are.equal(q:count(), 0);

				assert.is_true(q:push("one"));
				assert.is_true(q:push("two"));
				assert.is_true(q:push("three"));

				for i = 4, 10 do
					assert.is_true(q:push("hello"));
					assert.are.equal(q:count(), i, "count is not "..i.."("..q:count()..")");
				end
				assert.are.equal(q:push("hello"), nil, "queue overfull!");
				assert.are.equal(q:push("hello"), nil, "queue overfull!");
				assert.are.equal(q:pop(), "one", "queue item incorrect");
				assert.are.equal(q:pop(), "two", "queue item incorrect");
				assert.is_true(q:push("hello"));
				assert.is_true(q:push("hello"));
				assert.are.equal(q:pop(), "three", "queue item incorrect");
				assert.is_true(q:push("hello"));
				assert.are.equal(q:push("hello"), nil, "queue overfull!");
				assert.are.equal(q:push("hello"), nil, "queue overfull!");

				assert.are.equal(q:count(), 10, "queue count incorrect");

				for _ = 1, 10 do
					assert.are.equal(q:pop(), "hello", "queue item incorrect");
				end

				assert.are.equal(q:count(), 0, "queue count incorrect");
				assert.are.equal(q:pop(), nil, "empty queue pops non-nil result");
				assert.are.equal(q:count(), 0, "popping empty queue affects count");

				assert.are.equal(q:peek(), nil, "empty queue peeks non-nil result");
				assert.are.equal(q:count(), 0, "peeking empty queue affects count");

				assert.is_true(q:push(1));
				for i = 1, 1001 do
					assert.are.equal(q:pop(), i);
					assert.are.equal(q:count(), 0);
					assert.is_true(q:push(i+1));
					assert.are.equal(q:count(), 1);
				end
				assert.are.equal(q:pop(), 1002);
				assert.is_true(q:push(1));
				for i = 1, 1000 do
					assert.are.equal(q:pop(), i);
					assert.is_true(q:push(i+1));
				end
				assert.are.equal(q:pop(), 1001);
				assert.are.equal(q:count(), 0);
			end

			do
				-- Test queues that purge old items when pushing to a full queue
				local q = queue.new(10, true);

				for i = 1, 10 do
					q:push(i);
				end

				assert.are.equal(q:count(), 10);

				assert.is_true(q:push(11));
				assert.are.equal(q:count(), 10);
				assert.are.equal(q:pop(), 2); -- First item should have been purged
				assert.are.equal(q:peek(), 3);

				for i = 12, 32 do
					assert.is_true(q:push(i));
				end

				assert.are.equal(q:count(), 10);
				assert.are.equal(q:pop(), 23);
			end

			do
				-- Test iterator
				local q = queue.new(10, true);

				for i = 1, 10 do
					q:push(i);
				end

				local i = 0;
				for item in q:items() do
					i = i + 1;
					assert.are.equal(item, i, "unexpected item returned by iterator")
				end
			end

		end);
	end);
	describe("consume()", function ()
		it("should work", function ()
			local q = queue.new(10);
			for i = 1, 5 do
				q:push(i);
			end
			local c = 0;
			for i in q:consume() do
				assert(i == c + 1);
				assert(q:count() == (5-i));
				c = i;
			end
		end);

		it("should work even if items are pushed in the loop", function ()
			local q = queue.new(10);
			for i = 1, 5 do
				q:push(i);
			end
			local c = 0;
			for i in q:consume() do
				assert(i == c + 1);
				if c < 3 then
					assert(q:count() == (5-i));
				else
					assert(q:count() == (6-i));
				end

				c = i;

				if c == 3 then
					q:push(6);
				end
			end
			assert.equal(c, 6);
		end);
	end);
end);