util.roles: Return nil if the role has no explicit policy (fixes inheritance)
Previously, if the first inherited role had no opinion, it returned false and
prevented further consultation of other inherited roles.
This bug was found thanks to the implementation of missing test cases
identified through mutation testing.
-- Mock util.time
local now = 0; -- wibbly-wobbly... timey-wimey... stuff
local function later(n)
now = now + n; -- time passes at a different rate
end
package.loaded["util.time"] = {
now = function() return now; end
}
local throttle = require "util.throttle";
describe("util.throttle", function()
describe("#create()", function()
it("should be created with correct values", function()
now = 5;
local a = throttle.create(3, 10);
assert.same(a, { balance = 3, max = 3, rate = 0.3, t = 5 });
local a = throttle.create(3, 5);
assert.same(a, { balance = 3, max = 3, rate = 0.6, t = 5 });
local a = throttle.create(1, 1);
assert.same(a, { balance = 1, max = 1, rate = 1, t = 5 });
local a = throttle.create(10, 10);
assert.same(a, { balance = 10, max = 10, rate = 1, t = 5 });
local a = throttle.create(10, 1);
assert.same(a, { balance = 10, max = 10, rate = 10, t = 5 });
end);
end);
describe("#update()", function()
it("does nothing when no time has passed, even if balance is not full", function()
now = 5;
local a = throttle.create(10, 10);
for i=1,5 do
a:update();
assert.same(a, { balance = 10, max = 10, rate = 1, t = 5 });
end
a.balance = 0;
for i=1,5 do
a:update();
assert.same(a, { balance = 0, max = 10, rate = 1, t = 5 });
end
end);
it("updates only time when time passes but balance is full", function()
now = 5;
local a = throttle.create(10, 10);
for i=1,5 do
later(5);
a:update();
assert.same(a, { balance = 10, max = 10, rate = 1, t = 5 + i*5 });
end
end);
it("updates balance when balance has room to grow as time passes", function()
now = 5;
local a = throttle.create(10, 10);
a.balance = 0;
assert.same(a, { balance = 0, max = 10, rate = 1, t = 5 });
later(1);
a:update();
assert.same(a, { balance = 1, max = 10, rate = 1, t = 6 });
later(3);
a:update();
assert.same(a, { balance = 4, max = 10, rate = 1, t = 9 });
later(10);
a:update();
assert.same(a, { balance = 10, max = 10, rate = 1, t = 19 });
end);
it("handles 10 x 0.1s updates the same as 1 x 1s update ", function()
now = 5;
local a = throttle.create(1, 1);
a.balance = 0;
later(1);
a:update();
assert.same(a, { balance = 1, max = 1, rate = 1, t = now });
a.balance = 0;
for i=1,10 do
later(0.1);
a:update();
end
assert(math.abs(a.balance - 1) < 0.0001); -- incremental updates cause rounding errors
end);
end);
-- describe("po")
describe("#poll()", function()
it("should only allow successful polls until cost is hit", function()
now = 5;
local a = throttle.create(3, 10);
assert.same(a, { balance = 3, max = 3, rate = 0.3, t = 5 });
assert.is_true(a:poll(1)); -- 3 -> 2
assert.same(a, { balance = 2, max = 3, rate = 0.3, t = 5 });
assert.is_true(a:poll(2)); -- 2 -> 1
assert.same(a, { balance = 0, max = 3, rate = 0.3, t = 5 });
assert.is_false(a:poll(1)); -- MEEP, out of credits!
assert.is_false(a:poll(1)); -- MEEP, out of credits!
assert.same(a, { balance = 0, max = 3, rate = 0.3, t = 5 });
end);
it("should not allow polls more than the cost", function()
now = 0;
local a = throttle.create(10, 10);
assert.same(a, { balance = 10, max = 10, rate = 1, t = 0 });
assert.is_false(a:poll(11));
assert.same(a, { balance = 10, max = 10, rate = 1, t = 0 });
assert.is_true(a:poll(6));
assert.same(a, { balance = 4, max = 10, rate = 1, t = 0 });
assert.is_false(a:poll(5));
assert.same(a, { balance = 4, max = 10, rate = 1, t = 0 });
-- fractional
assert.is_true(a:poll(3.5));
assert.same(a, { balance = 0.5, max = 10, rate = 1, t = 0 });
assert.is_true(a:poll(0.25));
assert.same(a, { balance = 0.25, max = 10, rate = 1, t = 0 });
assert.is_false(a:poll(0.3));
assert.same(a, { balance = 0.25, max = 10, rate = 1, t = 0 });
assert.is_true(a:poll(0.25));
assert.same(a, { balance = 0, max = 10, rate = 1, t = 0 });
assert.is_false(a:poll(0.1));
assert.same(a, { balance = 0, max = 10, rate = 1, t = 0 });
assert.is_true(a:poll(0));
assert.same(a, { balance = 0, max = 10, rate = 1, t = 0 });
end);
end);
end);