File

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−
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−
+
−-- Mock util.time
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−local now = 0; -- wibbly-wobbly... timey-wimey... stuff
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−local function later(n)
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−	now = now + n; -- time passes at a different rate
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−end
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−package.loaded["util.time"] = {
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−	now = function() return now; end
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−}
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−
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−
+
−local throttle = require "util.throttle";
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−
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−describe("util.throttle", function()
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−	describe("#create()", function()
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−		it("should be created with correct values", function()
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−			now = 5;
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−			local a = throttle.create(3, 10);
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−			assert.same(a, { balance = 3, max = 3, rate = 0.3, t = 5 });
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−
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−			local a = throttle.create(3, 5);
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−			assert.same(a, { balance = 3, max = 3, rate = 0.6, t = 5 });
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−
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−			local a = throttle.create(1, 1);
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−			assert.same(a, { balance = 1, max = 1, rate = 1, t = 5 });
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−
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−			local a = throttle.create(10, 10);
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−			assert.same(a, { balance = 10, max = 10, rate = 1, t = 5 });
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−
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−			local a = throttle.create(10, 1);
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−			assert.same(a, { balance = 10, max = 10, rate = 10, t = 5 });
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−		end);
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−	end);
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−
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−	describe("#update()", function()
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−		it("does nothing when no time has passed, even if balance is not full", function()
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−			now = 5;
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−			local a = throttle.create(10, 10);
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−			for i=1,5 do
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−				a:update();
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−				assert.same(a, { balance = 10, max = 10, rate = 1, t = 5 });
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−			end
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−			a.balance = 0;
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−			for i=1,5 do
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−				a:update();
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−				assert.same(a, { balance = 0, max = 10, rate = 1, t = 5 });
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−			end
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−		end);
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−		it("updates only time when time passes but balance is full", function()
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−			now = 5;
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−			local a = throttle.create(10, 10);
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−			for i=1,5 do
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−				later(5);
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−				a:update();
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−				assert.same(a, { balance = 10, max = 10, rate = 1, t = 5 + i*5 });
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−			end
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−		end);
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−		it("updates balance when balance has room to grow as time passes", function()
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−			now = 5;
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−			local a = throttle.create(10, 10);
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−			a.balance = 0;
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−			assert.same(a, { balance = 0, max = 10, rate = 1, t = 5 });
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−
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−			later(1);
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−			a:update();
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−			assert.same(a, { balance = 1, max = 10, rate = 1, t = 6 });
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−
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−			later(3);
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−			a:update();
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−			assert.same(a, { balance = 4, max = 10, rate = 1, t = 9 });
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−
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−			later(10);
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−			a:update();
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−			assert.same(a, { balance = 10, max = 10, rate = 1, t = 19 });
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−		end);
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−		it("handles 10 x 0.1s updates the same as 1 x 1s update ", function()
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−			now = 5;
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−			local a = throttle.create(1, 1);
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−
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−			a.balance = 0;
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−			later(1);
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−			a:update();
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−			assert.same(a, { balance = 1, max = 1, rate = 1, t = now });
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−
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−			a.balance = 0;
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−			for i=1,10 do
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−				later(0.1);
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−				a:update();
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−			end
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−			assert(math.abs(a.balance - 1) < 0.0001); -- incremental updates cause rounding errors
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−		end);
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−	end);
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−
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−	-- describe("po")
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−
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−	describe("#poll()", function()
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−		it("should only allow successful polls until cost is hit", function()
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−			now = 5;
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−
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−			local a = throttle.create(3, 10);
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−			assert.same(a, { balance = 3, max = 3, rate = 0.3, t = 5 });
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−
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−			assert.is_true(a:poll(1));  -- 3 -> 2
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−			assert.same(a, { balance = 2, max = 3, rate = 0.3, t = 5 });
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−
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−			assert.is_true(a:poll(2));  -- 2 -> 1
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−			assert.same(a, { balance = 0, max = 3, rate = 0.3, t = 5 });
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−
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−			assert.is_false(a:poll(1)); -- MEEP, out of credits!
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−			assert.is_false(a:poll(1)); -- MEEP, out of credits!
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−			assert.same(a, { balance = 0, max = 3, rate = 0.3, t = 5 });
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−		end);
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−
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−		it("should not allow polls more than the cost", function()
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−			now = 0;
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−
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−			local a = throttle.create(10, 10);
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−			assert.same(a, { balance = 10, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_false(a:poll(11));
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−			assert.same(a, { balance = 10, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_true(a:poll(6));
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−			assert.same(a, { balance = 4, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_false(a:poll(5));
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−			assert.same(a, { balance = 4, max = 10, rate = 1, t = 0 });
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−
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−			-- fractional
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−			assert.is_true(a:poll(3.5));
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−			assert.same(a, { balance = 0.5, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_true(a:poll(0.25));
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−			assert.same(a, { balance = 0.25, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_false(a:poll(0.3));
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−			assert.same(a, { balance = 0.25, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_true(a:poll(0.25));
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−			assert.same(a, { balance = 0, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_false(a:poll(0.1));
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−			assert.same(a, { balance = 0, max = 10, rate = 1, t = 0 });
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−
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−			assert.is_true(a:poll(0));
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−			assert.same(a, { balance = 0, max = 10, rate = 1, t = 0 });
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−		end);
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−	end);
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−end);