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# Boolean Assertions
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Core boolean assertion functions for testing true/false conditions in Kotlin test code. These functions provide both direct value testing and lambda-based conditional testing with optional custom error messages.
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## Capabilities
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### assertTrue
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Asserts that a boolean expression or lambda result is true.
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```kotlin { .api }
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/**
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 * Asserts that the value is true with an optional message.
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 * @param actual The boolean value to test
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 * @param message Optional message to show if assertion fails
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 */
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fun assertTrue(actual: Boolean, message: String? = null)
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/**
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 * Asserts that the given block returns true with an optional message.
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 * @param message Optional message to show if assertion fails
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 * @param block Lambda function that returns a boolean
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 */
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inline fun assertTrue(message: String? = null, block: () -> Boolean)
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```
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**Usage Examples:**
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```kotlin
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import kotlin.test.assertTrue
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@Test
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fun testTrueConditions() {
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    // Direct boolean assertion
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    assertTrue(5 > 3)
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    assertTrue(5 > 3, "Five should be greater than three")
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    // Lambda-based assertion
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    assertTrue("List should not be empty") { 
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        listOf(1, 2, 3).isNotEmpty() 
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    }
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    // Complex condition testing
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    val user = User("Alice", 25)
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    assertTrue(user.isAdult())
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    assertTrue("User should be adult") { user.age >= 18 }
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}
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```
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### assertFalse
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Asserts that a boolean expression or lambda result is false.
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```kotlin { .api }
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/**
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 * Asserts that the value is false with an optional message.
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 * @param actual The boolean value to test
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 * @param message Optional message to show if assertion fails
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 */
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fun assertFalse(actual: Boolean, message: String? = null)
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/**
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 * Asserts that the given block returns false with an optional message.
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 * @param message Optional message to show if assertion fails
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 * @param block Lambda function that returns a boolean
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 */
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inline fun assertFalse(message: String? = null, block: () -> Boolean)
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```
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**Usage Examples:**
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```kotlin
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import kotlin.test.assertFalse
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@Test
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fun testFalseConditions() {
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    // Direct boolean assertion
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    assertFalse(3 > 5)
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    assertFalse(3 > 5, "Three should not be greater than five")
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    // Lambda-based assertion
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    assertFalse("List should be empty") { 
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        emptyList<String>().isNotEmpty() 
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    }
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    // Complex condition testing
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    val account = Account(balance = 0.0)
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    assertFalse(account.hasPositiveBalance())
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    assertFalse("Account should not be overdrawn") { account.balance < 0 }
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}
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```
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## Error Handling
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Both assertion functions will throw an `AssertionError` when the condition fails:
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- **assertTrue**: Throws when the value/block result is false
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- **assertFalse**: Throws when the value/block result is true
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Custom messages are included in the error to provide context about the failure:
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```kotlin
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// This will throw: AssertionError: Expected value to be true.
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assertTrue(false)
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// This will throw: AssertionError: User should be active.
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assertTrue(user.isActive, "User should be active")
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```