---
title: "XCTAssertTrue(_:_:file:line:)"
framework: xctest
role: symbol
role_heading: Function
path: "xctest/xctasserttrue(_:_:file:line:)"
---

# XCTAssertTrue(_:_:file:line:)

Asserts that an expression is true.

## Declaration

```swift
func XCTAssertTrue(_ expression: @autoclosure () throws -> Bool, _ message: @autoclosure () -> String = "", file: StaticString = #filePath, line: UInt = #line)
```

## Parameters

- `expression`: An expression of Boolean type.
- `message`: An optional description of a failure.
- `file`: The file where the failure occurs. The default is the filename of the test case where you call this function.
- `line`: The line number where the failure occurs. The default is the line number where you call this function.

## Discussion

Discussion This function generates a failure when expression == false and is equivalent to XCTAssert(_:_:file:line:).

## See Also

### Tests for True Conditions

- [XCTAssert(_:_:file:line:)](xctest/xctassert(_:_:file:line:).md)