fix of smart lockers

coroutines/src/commonTest/kotlin/SmartMutexTests.kt

@@ -0,0 +1,73 @@
+import dev.inmo.micro_utils.coroutines.SmartMutex
+import dev.inmo.micro_utils.coroutines.withLock
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.awaitCancellation
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.cancelAndJoin
+import kotlinx.coroutines.currentCoroutineContext
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.runTest
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+import kotlin.time.Duration.Companion.seconds
+
+class SmartMutexTests {
+    @Test
+    fun cancelledUnlockCompletesUnderContention() = runTest(timeout = 5.seconds) {
+        val mutex = SmartMutex.Mutable()
+
+        // Delegate this acquisition's release to another coroutine. The
+        // unconfined collector runs while lock() still holds its internal mutex.
+        val releaser = launch(Dispatchers.Unconfined) {
+            mutex.lockStateFlow.first { it }
+            currentCoroutineContext().cancel()
+            mutex.unlock()
+        }
+
+        // Keep acquisition on the normal test dispatcher so the collector
+        // attempts cancelled cleanup before the internal mutex is released.
+        mutex.lock()
+        releaser.join()
+
+        assertTrue(releaser.isCancelled)
+        assertFalse(mutex.isLocked, "Cancellation must not prevent the delegated unlock")
+        assertTrue(mutex.tryLock())
+        assertTrue(mutex.unlock())
+    }
+
+    @Test
+    fun cancellingWithLockBodyReleasesMutex() = runTest(timeout = 5.seconds) {
+        val mutex = SmartMutex.Mutable()
+        val holder = launch(Dispatchers.Unconfined) {
+            mutex.withLock {
+                awaitCancellation()
+            }
+        }
+        assertTrue(mutex.isLocked)
+
+        holder.cancelAndJoin()
+
+        assertFalse(mutex.isLocked)
+    }
+
+    @Test
+    fun cancelledWaiterDoesNotEnterOrReleaseHeldMutex() = runTest(timeout = 5.seconds) {
+        val mutex = SmartMutex.Mutable()
+        var entered = false
+        mutex.withLock {
+            val waiter = launch(Dispatchers.Unconfined) {
+                mutex.withLock {
+                    entered = true
+                }
+            }
+
+            waiter.cancelAndJoin()
+
+            assertFalse(entered)
+            assertTrue(mutex.isLocked)
+        }
+        assertFalse(mutex.isLocked)
+    }
+}

coroutines/src/commonTest/kotlin/SmartRWLockerTests.kt

@@ -9,6 +9,7 @@ import kotlin.test.assertEquals
 import kotlin.test.assertFails
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue
+import kotlin.time.Duration.Companion.days
 import kotlin.time.Duration.Companion.seconds
 
 class SmartRWLockerTests {
@@ -109,6 +110,59 @@ class SmartRWLockerTests {
         }
     }
 
+    @Test
+    fun failureOnReadFreeingRead() = runTest {
+        val locker = SmartRWLocker()
+        val job = launch {
+            locker.withReadAcquire {
+                while (isActive) {
+                    delay(1.days)
+                }
+            }
+        }
+
+        locker.readSemaphore.permitsStateFlow.first {
+            it == locker.readSemaphore.maxPermits - 1
+        }
+        job.cancelAndJoin()
+        locker.readSemaphore.permitsStateFlow.first {
+            it == locker.readSemaphore.maxPermits
+        }
+    }
+
+    @Test
+    fun cancelledReaderReleasesPermitUnderContention() = runTest(timeout = 5.seconds) {
+        val locker = SmartRWLocker(readPermits = 2)
+        val reader = launch(Dispatchers.Unconfined) {
+            locker.withReadAcquire {
+                awaitCancellation()
+            }
+        }
+        assertEquals(1, locker.readSemaphore.freePermits)
+
+        // Observe the second acquisition synchronously while it still holds the
+        // semaphore's internal mutex. Cancelling the unconfined reader makes its
+        // cleanup contend for that mutex before the acquisition can release it.
+        val cancellation = launch(Dispatchers.Unconfined) {
+            locker.readSemaphore.permitsStateFlow.first { it == 0 }
+            reader.cancel()
+        }
+
+        // Keep this acquisition on the normal test dispatcher: making it
+        // unconfined would change the ordering that forces cleanup contention.
+        locker.withReadAcquire {
+            cancellation.join()
+            reader.join()
+            assertTrue(reader.isCancelled)
+            assertEquals(
+                1,
+                locker.readSemaphore.freePermits,
+                "The cancelled reader must release its permit while the other reader still holds one"
+            )
+        }
+        assertEquals(2, locker.readSemaphore.freePermits)
+    }
+
     @Test
     fun simpleWithReadAcquireTest() {
         val locker = SmartRWLocker()

coroutines/src/commonTest/kotlin/SmartSemaphoreTests.kt

@@ -0,0 +1,104 @@
+import dev.inmo.micro_utils.coroutines.SmartSemaphore
+import dev.inmo.micro_utils.coroutines.withAcquire
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.awaitCancellation
+import kotlinx.coroutines.cancelAndJoin
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.runTest
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+import kotlin.time.Duration.Companion.seconds
+
+class SmartSemaphoreTests {
+    @Test
+    fun cancelledHolderReleasesPermitUnderContention() = runTest(timeout = 5.seconds) {
+        val semaphore = SmartSemaphore.Mutable(permits = 2)
+        val holder = launch(Dispatchers.Unconfined) {
+            semaphore.withAcquire {
+                awaitCancellation()
+            }
+        }
+        assertEquals(1, semaphore.freePermits)
+
+        // The synchronous observer cancels the holder while the second
+        // acquisition still owns the semaphore's internal changes mutex.
+        val cancellation = launch(Dispatchers.Unconfined) {
+            semaphore.permitsStateFlow.first { it == 0 }
+            holder.cancel()
+        }
+        semaphore.withAcquire {
+            cancellation.join()
+            holder.join()
+            assertTrue(holder.isCancelled)
+            assertEquals(1, semaphore.freePermits, "The cancelled holder must return its permit")
+        }
+        assertEquals(2, semaphore.freePermits)
+    }
+
+    @Test
+    fun cancelledAcquireReturnsPartialPermitsUnderContention() = runTest(timeout = 5.seconds) {
+        // One permit belongs to another holder; the waiter can acquire two
+        // permits immediately, but must wait for the third.
+        val semaphore = SmartSemaphore.Mutable(permits = 3, acquiredPermits = 1)
+        lateinit var waiter: kotlinx.coroutines.Job
+        val cancellation = launch(Dispatchers.Unconfined) {
+            semaphore.permitsStateFlow.first { it == 1 }
+            waiter.cancel()
+        }
+        waiter = launch(Dispatchers.Unconfined) {
+            semaphore.acquire(3)
+        }
+        assertEquals(0, semaphore.freePermits)
+        assertFalse(waiter.isCompleted)
+
+        // Publishing this release resumes the observer while the internal
+        // mutex is held. The cancelled acquire must wait to roll back safely.
+        semaphore.release()
+        cancellation.join()
+        waiter.join()
+        assertTrue(waiter.isCancelled)
+        assertEquals(3, semaphore.freePermits, "Cancellation must return both partially acquired permits")
+        semaphore.withAcquire(3) {
+            assertEquals(0, semaphore.freePermits)
+        }
+        assertEquals(3, semaphore.freePermits)
+    }
+
+    @Test
+    fun cancelledAcquireWithoutPermitsDoesNotReleaseAnotherHoldersPermit() = runTest(timeout = 5.seconds) {
+        val semaphore = SmartSemaphore.Mutable(permits = 1, acquiredPermits = 1)
+        val waiter = launch(Dispatchers.Unconfined) {
+            semaphore.acquire()
+        }
+        assertFalse(waiter.isCompleted)
+
+        waiter.cancelAndJoin()
+        assertEquals(0, semaphore.freePermits, "A cancelled waiter that acquired nothing must release nothing")
+        assertTrue(semaphore.release())
+        assertEquals(1, semaphore.freePermits)
+    }
+
+    @Test
+    fun tryAcquireUsesAvailablePermits() = runTest {
+        val semaphore = SmartSemaphore.Mutable(permits = 3)
+        assertTrue(semaphore.tryAcquire(2))
+        assertEquals(1, semaphore.freePermits)
+        assertTrue(semaphore.tryAcquire())
+        assertEquals(0, semaphore.freePermits)
+        assertTrue(semaphore.release(3))
+        assertEquals(3, semaphore.freePermits)
+    }
+
+    @Test
+    fun tryAcquireWithInsufficientPermitsLeavesStateUnchanged() = runTest {
+        val semaphore = SmartSemaphore.Mutable(permits = 3, acquiredPermits = 2)
+        assertFalse(semaphore.tryAcquire(2))
+        assertEquals(1, semaphore.freePermits)
+        semaphore.acquire()
+        assertFalse(semaphore.tryAcquire())
+        assertEquals(0, semaphore.freePermits)
+    }
+}