Background compiles give way to the lander: the Logbook statistics and the results refresher wait while [logbook] lander_lock is fresh (under 60 min); the statistics tools run below normal priority and a timeout ends the whole tree (an orphaned cl.exe went on compiling main at normal priority); a retried statistics run no longer relogs the same commits

tests/test_logbook.py

@@ -58,6 +58,54 @@ class LogbookAuto(HarborCase):
         self.assertTrue(entry["at"].endswith("Z"))
         self.assertFalse(logbook_auto.refresh(self.h.project)["changed"])
 
+    def test_waits_for_the_lander_and_a_failed_stats_run_logs_nothing_twice(self):
+        import os
+        import time
+        from unittest import mock
+        logbook_auto._save_state(self.h.project, {"last_head": self.first})
+        lock = self.dir / "lander-busy.lock"
+        lock.write_text("x", encoding="utf-8")
+        self.h.project.logbook.update(lander_lock=str(lock), stats_repo=str(self.dir / "stats"))
+        out = logbook_auto.refresh(self.h.project)
+        self.assertFalse(out["changed"])
+        self.assertIn("lander", out["waiting"])
+        self.assertEqual(logbook.read_all(self.h.project)["log"], [])
+        old = time.time() - 61 * 60
+        os.utime(lock, (old, old))                                              # stale: ignored
+        with mock.patch.object(logbook_auto, "rebuild_stats", side_effect=RuntimeError("timed out")):
+            out = logbook_auto.refresh(self.h.project)
+            self.assertEqual((out["entries"], out["stats_error"]), (1, "timed out"))
+            again = logbook_auto.refresh(self.h.project)                       # the statistics are retried ...
+            self.assertIn("stats_error", again)
+            self.assertNotIn("entries", again)                                 # ... but the commit is not relogged
+        self.assertEqual(len(logbook.read_all(self.h.project)["log"]), 1)
+
+
+class LanderGate(unittest.TestCase):
+    def test_run_low_lowers_priority_and_ends_the_tree_on_timeout(self):
+        import os
+        import sys
+        import time
+        from harbor import lander_gate
+        script = "import subprocess, sys, time; subprocess.Popen([sys.executable, '-c', 'import time; time.sleep(60)']);" \
+                 " print('ok', flush=True); time.sleep(60)"
+        from unittest import mock
+        seen = {}
+        real = subprocess.Popen
+
+        def popen(argv, **kw):
+            seen.update(kw)
+            return real([sys.executable, "-c", "pass"], stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
+
+        with mock.patch.object(lander_gate.subprocess, "Popen", popen):
+            self.assertEqual(lander_gate.run_low(["x"], 60).returncode, 0)
+        if os.name == "nt":
+            self.assertTrue(seen["creationflags"] & subprocess.BELOW_NORMAL_PRIORITY_CLASS)
+        start = time.monotonic()
+        with self.assertRaises(subprocess.TimeoutExpired):
+            lander_gate.run_low([sys.executable, "-c", script], 3)
+        self.assertLess(time.monotonic() - start, 45)                         # the grandchild did not hold the pipes
+
 
 class ProgressMapTests(HarborCase):
     """GET /api/logbook/progress-map: units, tiers and the headline, by the Logbook's own definitions."""