Locust stuck in "Shape worker starting" when restarting a test from the webUI

[ancameme]

When restarting a test (that uses LoadTestShape) from the webUI, the test gets stuck in "Shape worker starting" (until tick() signals another change in shape).

Expected behavior

Test should start immediately without waiting on a change in load shape.

Actual behavior

Test waits on a change in load shape

Example file:

import datetime
from locust import HttpUser, TaskSet, task, constant
from locust import LoadTestShape

class UserTasks(TaskSet):
    @task
    def something(self):
        self.client.post(f'/')

class WebsiteUser(HttpUser):
    wait_time = constant(1)
    tasks = [UserTasks]

class upAndDown(LoadTestShape):
    def tick(self):
        if datetime.datetime.now().minute % 2 == 0:
            user_count = 4
        else:
            user_count = 5
        return (user_count, 2)

Start test then stop. Restart the test from webUI (New test). The test won't start running until the minute changes (and tick() returns a different user_count).

Seems to be due to

            elif self.shape_last_state == new_state:
                gevent.sleep(1)

in runners.py > Runner > shape_worker

and self.shape_last_state = None not being reset in stop()

• Python version: 3.6.9
• Locust version: 1.2.1

[max-rocket-internet]

True.

Are you able to make a PR?

[ancameme]

@max-rocket-internet Sorry, no