File

spec/util_array_spec.lua @ 13182:c48ae06e24d6

util.datamanager: Fix indexing first item if not at the very start If the first item does not start at position 0 then the index function produces a phantom first entry covering position zero until where the real first item starts. When using the index, this would make it either appear as the first item was missing or cause an off-by-one issue with remaining items.
author Kim Alvefur <zash@zash.se>
date Mon, 10 Jul 2023 17:19:05 +0200
parent 11787:3ae6fa901a8b
child 13245:ffe4adbd2af9
line wrap: on
line source

local array = require "util.array";
describe("util.array", function ()
	describe("creation", function ()
		describe("from table", function ()
			it("works", function ()
				local a = array({"a", "b", "c"});
				assert.same({"a", "b", "c"}, a);
			end);
		end);

		describe("from iterator", function ()
			it("works", function ()
				-- collects the first value, ie the keys
				local a = array(ipairs({true, true, true}));
				assert.same({1, 2, 3}, a);
			end);
		end);

		describe("collect", function ()
			it("works", function ()
				-- collects the first value, ie the keys
				local a = array.collect(ipairs({true, true, true}));
				assert.same({1, 2, 3}, a);
			end);
		end);

	end);

	describe("metatable", function ()
		describe("operator", function ()
			describe("addition", function ()
				it("works", function ()
					local a = array({ "a", "b" });
					local b = array({ "c", "d" });
					assert.same({"a", "b", "c", "d"}, a + b);
				end);
			end);

			describe("equality", function ()
				it("works", function ()
					local a1 = array({ "a", "b" });
					local a2 = array({ "a", "b" });
					local b = array({ "c", "d" });
					assert.truthy(a1 == a2);
					assert.falsy(a1 == b);
					assert.falsy(a1 == { "a", "b" }, "Behavior of metatables changed in Lua 5.3");
				end);
			end);

			describe("division", function ()
				it("works", function ()
					local a = array({ "a", "b", "c" });
					local b = a / function (i) if i ~= "b" then return i .. "x" end end;
					assert.same({ "ax", "cx" }, b);
				end);
			end);

		end);
	end);

	describe("methods", function ()
		describe("map", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				local b = a:map(string.upper);
				assert.same({ "A", "B", "C" }, b);
			end);
		end);

		describe("filter", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				a:filter(function (i) return i ~= "b" end);
				assert.same({ "a", "c" }, a);
			end);
		end);

		describe("sort", function ()
			it("works", function ()
				local a = array({ 5, 4, 3, 1, 2, });
				a:sort();
				assert.same({ 1, 2, 3, 4, 5, }, a);
			end);
		end);

		describe("unique", function ()
			it("works", function ()
				local a = array({ "a", "b", "c", "c", "a", "b" });
				a:unique();
				assert.same({ "a", "b", "c" }, a);
			end);
		end);

		describe("pluck", function ()
			it("works", function ()
				local a = array({ { a = 1, b = -1 }, { a = 2, b = -2 }, });
				a:pluck("a");
				assert.same({ 1, 2 }, a);
			end);
		end);


		describe("reverse", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				a:reverse();
				assert.same({ "c", "b", "a" }, a);
			end);
		end);

		-- TODO :shuffle

		describe("append", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				a:append(array({ "d", "e", }));
				assert.same({ "a", "b", "c", "d", "e" }, a);
			end);
		end);

		describe("push", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				a:push("d"):push("e");
				assert.same({ "a", "b", "c", "d", "e" }, a);
			end);
		end);

		describe("pop", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				assert.equal("c", a:pop());
				assert.same({ "a", "b", }, a);
			end);
		end);

		describe("concat", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				assert.equal("a,b,c", a:concat(","));
			end);
		end);

		describe("length", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				assert.equal(3, a:length());
			end);
		end);

		describe("slice", function ()
			it("works", function ()
				local a = array({ "a", "b", "c" });
				assert.equal(array.slice(a, 1, 2), array{ "a", "b" });
				assert.equal(array.slice(a, 1, 3), array{ "a", "b", "c" });
				assert.equal(array.slice(a, 2, 3), array{ "b", "c" });
				assert.equal(array.slice(a, 2), array{ "b", "c" });
				assert.equal(array.slice(a, -4), array{ "a", "b", "c" });
				assert.equal(array.slice(a, -3), array{ "a", "b", "c" });
				assert.equal(array.slice(a, -2), array{ "b", "c" });
				assert.equal(array.slice(a, -1), array{ "c" });
			end);

			it("can mutate", function ()
				local a = array({ "a", "b", "c" });
				assert.equal(a:slice(-1), array{"c"});
				assert.equal(a, array{"c"});
			end);
		end);
	end);

	-- TODO The various array.foo(array ina, array outa) functions
end);