util.promise: Remove some redundant checks, add tests confirming redundancy
This lines don't appear to do anything useful, and all tests pass when they
are removed. Discovered via mutation testing.
I added extra tests to exercise this code, because I wasn't certain that there
were no side-effects caused by removal. Everything appears to be fine, thanks
to the "pending" check at the start of promise_settle().
local timer = require "util.timer";
local setmetatable = setmetatable;
local _ENV = nil;
-- luacheck: std none
local watchdog_methods = {};
local watchdog_mt = { __index = watchdog_methods };
local function new(timeout, callback)
local watchdog = setmetatable({
timeout = timeout;
callback = callback;
timer_id = nil;
}, watchdog_mt);
watchdog:reset(); -- Kick things off
return watchdog;
end
function watchdog_methods:reset(new_timeout)
if new_timeout then
self.timeout = new_timeout;
end
if self.timer_id then
timer.reschedule(self.timer_id, self.timeout+1);
else
self.timer_id = timer.add_task(self.timeout+1, function ()
return self:callback();
end);
end
end
function watchdog_methods:cancel()
if self.timer_id then
timer.stop(self.timer_id);
self.timer_id = nil;
end
end
return {
new = new;
};