cc dist_lock: make SetNotEnabled test pass quicker

commit_hash:cbd993fefc68ba8f8d2f619500e86960afb1a693

Author: Anton3

core/src/dist_lock/dist_lock_test.cpp

@@ -206,7 +206,10 @@ UTEST_MT(LockedWorker, SetNotEnabled, 3) {
 
     EXPECT_TRUE(work.WaitForLocked(false, utest::kMaxTestWaitTime));
     work.SetWorkLoopOn(true);
-    EXPECT_FALSE(work.WaitForLocked(true, utest::kMaxTestWaitTime));
+    // Expect the disabled worker to not reacquire the lock.
+    // In case of a bug in DistLockedWorker, kAttemptTimeout will be enough to "probably" discover the bug.
+    // In case of no bug, the test will not become flaky due to a smaller timeout.
+    EXPECT_FALSE(work.WaitForLocked(true, kAttemptTimeout));
 
     locked_worker.Stop();
 }

core/utest/include/userver/utest/utest.hpp

@@ -28,6 +28,9 @@ namespace utest {
 
 /// The maximum time a typical test is allowed to execute. If exceeded, a
 /// deadlock is assumed. This time must not be too low to avoid flaky tests.
+///
+/// Use this timeout for awaiting something that is expected to complete.
+/// Use appropriate shorter timeouts for awaiting something that is not expected to ever complete.
 inline constexpr std::chrono::seconds kMaxTestWaitTime(20);
 
 }  // namespace utest