diff --git a/coroutines/src/commonTest/kotlin/SmartRWLockerTests.kt b/coroutines/src/commonTest/kotlin/SmartRWLockerTests.kt
index cef0ff93526..75fd251d17b 100644
--- a/coroutines/src/commonTest/kotlin/SmartRWLockerTests.kt
+++ b/coroutines/src/commonTest/kotlin/SmartRWLockerTests.kt
@@ -1,10 +1,6 @@
-import dev.inmo.micro_utils.coroutines.SmartRWLocker
-import dev.inmo.micro_utils.coroutines.withReadAcquire
-import dev.inmo.micro_utils.coroutines.withWriteLock
-import kotlinx.coroutines.CoroutineStart
-import kotlinx.coroutines.delay
-import kotlinx.coroutines.joinAll
-import kotlinx.coroutines.launch
+import dev.inmo.micro_utils.coroutines.*
+import kotlinx.coroutines.*
+import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.test.runTest
@@ -57,4 +53,99 @@ class SmartRWLockerTests {
             assertEquals(expected = readAndWriteWorkers, actual = doneWrites)
         }
     }
+
+    @Test
+    fun simpleWithWriteLockTest() {
+        val locker = SmartRWLocker()
+
+        runTest {
+            locker.withWriteLock {
+                assertEquals(0, locker.readSemaphore.freePermits)
+                assertEquals(true, locker.writeMutex.isLocked)
+            }
+            assertEquals(Int.MAX_VALUE, locker.readSemaphore.freePermits)
+            assertEquals(false, locker.writeMutex.isLocked)
+        }
+    }
+
+    @Test
+    fun failureWithWriteLockTest() {
+        val locker = SmartRWLocker()
+
+        val exception = IllegalArgumentException()
+        try {
+            runTest {
+                val subscope = kotlinx.coroutines.CoroutineScope(this.coroutineContext)
+                var happenException: Throwable? = null
+                try {
+                    locker.withWriteLock {
+                        val checkFunction = fun (): Deferred<Unit> {
+                            return subscope.async {
+                                assertEquals(0, locker.readSemaphore.freePermits)
+                                assertEquals(true, locker.writeMutex.isLocked)
+                                throw exception
+                            }
+                        }
+                        doInDefault {
+                            assertEquals(0, locker.readSemaphore.freePermits)
+                            assertEquals(true, locker.writeMutex.isLocked)
+                            checkFunction().await()
+                        }
+                    }
+                } catch (e: Exception) {
+                    happenException = e
+                }
+                if (exception != happenException) {
+                    assertEquals(exception, happenException ?.cause)
+                }
+                assertEquals(Int.MAX_VALUE, locker.readSemaphore.freePermits)
+                assertEquals(false, locker.writeMutex.isLocked)
+            }
+        } catch (e: Exception) {
+            assertEquals(exception, e)
+        }
+    }
+
+    @Test
+    fun simpleWithReadAcquireTest() {
+        val locker = SmartRWLocker()
+
+        runTest {
+            locker.withReadAcquire {
+                assertEquals(Int.MAX_VALUE - 1, locker.readSemaphore.freePermits)
+                assertEquals(false, locker.writeMutex.isLocked)
+                locker.withReadAcquire {
+                    assertEquals(Int.MAX_VALUE - 2, locker.readSemaphore.freePermits)
+                    assertEquals(false, locker.writeMutex.isLocked)
+                }
+            }
+            assertEquals(Int.MAX_VALUE, locker.readSemaphore.freePermits)
+            assertEquals(false, locker.writeMutex.isLocked)
+        }
+    }
+
+    @Test
+    fun simple2WithWriteLockTest() {
+        val locker = SmartRWLocker()
+
+        val unlockDelay = 1000L // 1 sec
+        var unlocked: Boolean = false
+        runTest {
+            launch {
+                locker.withReadAcquire {
+                    delay(unlockDelay)
+                }
+                unlocked = true
+            }
+            locker.readSemaphore.permitsStateFlow.first { it == Int.MAX_VALUE - 1 }
+            assertEquals(false, unlocked)
+            locker.withWriteLock {
+                assertEquals(true, unlocked)
+                assertEquals(0, locker.readSemaphore.freePermits)
+                assertEquals(true, locker.writeMutex.isLocked)
+            }
+            assertEquals(Int.MAX_VALUE, locker.readSemaphore.freePermits)
+            assertEquals(false, locker.writeMutex.isLocked)
+        }
+    }
 }