File

spec/util_iterators_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
parent 9328:a9592107021b
child 12744:e894677359e5
line wrap: on
line source

local iter = require "util.iterators";

describe("util.iterators", function ()
	describe("join", function ()
		it("should produce a joined iterator", function ()
			local expect = { "a", "b", "c", 1, 2, 3 };
			local output = {};
			for x in iter.join(iter.values({"a", "b", "c"})):append(iter.values({1, 2, 3})) do
				table.insert(output, x);
			end
			assert.same(output, expect);
		end);
	end);

	describe("sorted_pairs", function ()
		it("should produce sorted pairs", function ()
			local orig = { b = 1, c = 2, a = "foo", d = false };
			local n, last_key = 0, nil;
			for k, v in iter.sorted_pairs(orig) do
				n = n + 1;
				if last_key then
					assert(k > last_key, "Expected "..k.." > "..last_key)
				end
				assert.equal(orig[k], v);
				last_key = k;
			end
			assert.equal("d", last_key);
			assert.equal(4, n);
		end);

		it("should allow a custom sort function", function ()
			local orig = { b = 1, c = 2, a = "foo", d = false };
			local n, last_key = 0, nil;
			for k, v in iter.sorted_pairs(orig, function (a, b) return a > b end) do
				n = n + 1;
				if last_key then
					assert(k < last_key, "Expected "..k.." > "..last_key)
				end
				assert.equal(orig[k], v);
				last_key = k;
			end
			assert.equal("a", last_key);
			assert.equal(4, n);
		end);
	end);
end);