def test_get_result_timeout(self):
"""Try to get the result with a timeout while the Promise is pending.
"""
def executor(on_fulfilled, on_rejected):
pass
p = Promise(executor)
with pytest.raises(TimeoutError):
p.result(0)
def test_async_failing_call(self):
"""Try to get the result of a failing Promise while it's pending."""
class Err(Exception):
pass
def executor(on_fulfilled, on_rejected):
Timer(0.001, on_rejected, args=[Err()]).start()
p = Promise(executor)
with pytest.raises(Err):
p.result()
def test_executor_raising_error(self):
"""Make a Promise with an executor raising an error and get result."""
class Err(Exception):
pass
def executor(on_fulfilled, on_rejected):
raise Err()
p = Promise(executor)
with pytest.raises(Err):
p.result()
def test_synchronous_call_failing(self):
"""Make a Promise rejected by a synchronous executor and get result."""
class Err(Exception):
pass
def executor(on_fulfilled, on_rejected):
on_rejected(Err())
p = Promise(executor)
with pytest.raises(Err):
p.result()
def test_asynchronous_call(self):
"""Make a Promise fulfilled after the call to result()."""
def executor(on_fulfilled, on_rejected):
Timer(0.001, on_fulfilled, args=['OK']).start()
p = Promise(executor)
assert p.result() == 'OK'
def test_synchronous_call(self):
"""Make a Promise fulfilled by a synchronous function and get result"""
def executor(on_fulfilled, on_rejected):
on_fulfilled(3)
p = Promise(executor)
assert p.result() is 3
def test_then_sync_call(self):
"""Test to chain a callback using then() on an fulfilled Promise."""
def _callback(arg):
assert arg is 23
return arg * 2
p = Promise(lambda ok, error: ok(23))
p2 = p.then(_callback)
assert p2.result(0.01) is 46
assert p.result(0.01) is 23
def test_then_async_call(self):
"""Chain a callback using then() on an not-yet fulfilled Promise."""
_fulfill = []
def _init(ok, error):
_fulfill.append(ok)
def _callback(arg):
assert arg is 23
return arg * 2
p = Promise(_init)
p2 = p.then(_callback)
_fulfill[0](23) # fulfill the Promise now.
assert p2.result(0.01) is 46
assert p.result(0.01) is 23
