copy test from broken pr #3232 for scaling in non-running blocks

parsl/tests/test_scaling/test_scale_down_htex_unregistered.py

@@ -0,0 +1,74 @@
+import logging
+import time
+
+import pytest
+
+import parsl
+
+from parsl import File, python_app
+from parsl.jobs.states import JobState, TERMINAL_STATES
+from parsl.providers import LocalProvider
+from parsl.channels import LocalChannel
+from parsl.launchers import SingleNodeLauncher
+from parsl.config import Config
+from parsl.executors import HighThroughputExecutor
+
+logger = logging.getLogger(__name__)
+
+_max_blocks = 1
+_min_blocks = 0
+
+
+def local_config():
+    return Config(
+        executors=[
+            HighThroughputExecutor(
+                heartbeat_period=1,
+                heartbeat_threshold=2,
+                poll_period=100,
+                label="htex_local",
+                address="127.0.0.1",
+                max_workers=1,
+                encrypted=True,
+                launch_cmd="sleep inf",
+                provider=LocalProvider(
+                    channel=LocalChannel(),
+                    init_blocks=1,
+                    max_blocks=_max_blocks,
+                    min_blocks=_min_blocks,
+                    launcher=SingleNodeLauncher(),
+                ),
+            )
+        ],
+        max_idletime=0.5,
+        strategy='htex_auto_scale',
+        strategy_period=0.1
+    )
+
+
+# see issue #1885 for details of failures of this test.
+# at the time of issue #1885 this test was failing frequently
+# in CI.
+@pytest.mark.local
+def test_scaledown_with_register(try_assert):
+    dfk = parsl.dfk()
+    htex = dfk.executors['htex_local']
+
+    num_managers = len(htex.connected_managers())
+    assert num_managers == 0, "Expected 0 managers at start"
+
+    try_assert(lambda: len(htex.status()),
+               fail_msg="Expected 1 block at start")
+
+    s = htex.status()
+    assert s['0'].state == JobState.RUNNING, "Expected block to be in RUNNING"
+
+    def check_zero_blocks():
+        s = htex.status()
+        return len(s) == 1 and s['0'].state in TERMINAL_STATES
+
+    try_assert(
+        check_zero_blocks,
+        fail_msg="Expected 0 blocks after idle scaledown",
+        timeout_ms=15000,
+    )