Open Radar

 
When using `XCUIApplication`’s `launchArguments` array to pass arguments into the application being tested, arguments that contain line breaks (i.e `\n`) are incorrectly escaped and become split across the line break when the app tries to read them from `ProcessInfo.processInfo.arguments`.

- Download the LaunchArgumentBugDemo.zip attachment
- Unzip the Xcode project and open it
- Hit CMD + U to run the tests
- Observe that testWithMultilineString() fails with the following error:

> XCTAssertEqual failed: ("This is a") is not equal to ("This is a
multiline string!")

In the demo app, the following value is passed into the `launchArguments` array:

```
let contents = """
This is a
multiline string!
"""

let app = XCUIApplication()
app.launchArguments = [contents]
app.launch()
```

The expectation is that `ProcessInfo.processInfo.arguments` should contain an argument with the value `”This is a\nmultiline string!”`, but the test fails because the array actually contains two arguments `”This is a”` and `”multiline string!”`. This is not expected.