Try stop with SIGINT first, pass timeout to constructor

freqtrade/tests/test_watchdog.py

@@ -16,3 +16,24 @@ def test_watchdog_kill(caplog):
     log = ["Watchdog started", "Watchdog stopped"]
     for line in log:
         assert line in caplog.text
+
+
+def test_try_kill_failed(mocker):
+    mocker.patch("os.kill")
+    mocker.patch("os.waitpid", return_value=(0, 0))
+    watchdog = Watchdog(1, 1)
+    assert watchdog.try_kill(0) is False
+
+
+def test_try_kill_success(mocker):
+    mocker.patch("os.kill")
+    mocker.patch("os.waitpid", return_value=(0, 1))
+    watchdog = Watchdog(1, 1)
+    assert watchdog.try_kill(0) is True
+
+
+def test_try_kill_error(mocker):
+    mocker.patch("os.kill")
+    mocker.patch("os.waitpid", side_effect=OSError)
+    watchdog = Watchdog(1, 1)
+    assert watchdog.try_kill(0) is True