Wsrtjtyk

I'm new to the Xcode User Interface testing framework. I can successfully manipulate the screen elements, but cannot work out how to produce a meaningful assertion about what text is visible in a scrolling view.

The test I would like to write would go as follows: launch the app, type lots of text into a text view (enough that the first line scrolls out of view), assert that the first line of text is not visible, scroll the view back up to the top, then assert that the first line is now visible. Note that the purpose of this test is to ensure my app has wired things up correctly, not to test Apple's code.

XCUIApplication allows me to type into my NSTextView instance, and also allows me to scroll the associated NSScrollView. But how do I assert whether the first line of text is currently visible? The value attribute on XCUIElement provides the entire text content of the view, whether or not it is currently displayed.

The accessibilityRange(forLine:) and accessibilityString(for:) methods on NSTextView would be ideal, but I can't see how to access them as the UI test only has access to an XCUIElement, not the underlying NSTextView.

Have I missed something, or is there a better way to approach this?

If you set the accessibility identifier in the storyboard or in code for the text view you can get the text view via (assuming you gave it the id "textview1" and the window it's in has the default accessibility identifier of "Window"):

let textview1TextView = app.windows["Window"].textViews["textview1"]

but that won't actually get you what you need.

Instead, set the accessibility identifier of the scrollview and get that:

let scrollview = app.windows["Window"].scrollViews["scrollview1"]

Then use that to get the scrollbars (you should only have one in this case; you can use scrollbars.count to check.

let scrollbars = scrollview.scrollBars

print("scrollbars count: (scrollbars.count)")

Then you can use the value attribute of the scrollbar to get it's value:
(you're converting a XCUIElemenTypeQueryProvider into an XCUIElement so you can get it's value):

let val = scrollbars.element.value

it will be 0 at the top and a floating point value when scrolled (one line of text in my test code showed a value of {{0.02409638554216868}}.

Documentation that will help you explore further:

XCUIElementTypeQueryProvider

XCUIElementAttributes

Note that you can put a breakpoint in the middle of your test, run it and then use the debugger console to examine things:

(lldb) po scrollbars.element.value

    t =   749.66s Find the ScrollBar ▿ Optional<Any>

  - some : 0



(lldb) po scrollbars.element.value

    t =   758.17s Find the ScrollBar ▿ Optional<Any>

  - some : 0.05421686746987952

and while in the debugger you can even interact with your app's window to scroll it manually (which is what I did between typing in those two po calls), or perhaps add text and so on.

OK OP now noted that they're interested in the specific text showing or not rather than the first line in view or not (which is what I previously answered above).

Here's a bit of a hack, but I think it'll work:

Use XCUICoordinate's click(forDuration:, thenDragTo:) method to select the first line of text (use the view frame to calculate coordinates) and then use the typeKey( modifierFlags:) to invoke the edit menu "copy" command. Then use NSPasteboard methods to get the pasteboard contents and check the text.

Here's a quick test I did to validate the approach (selecting the first line of text using XCUICoordinate as noted above is left as an exercise for the reader):

NSPasteboard.general.clearContents()



// stopped at break point on next line and I manually selected the text of the first line of text in my test app and then hit continue in the debugger



textview1TextView.typeKey("c", modifierFlags:.command)

print( NSPasteboard.general.pasteboardItems?.first?.string(forType: NSPasteboard.PasteboardType.string) ?? "none" );

-> "the text of the first line" was printed to the console.

Note that you can scroll the selection off screen so you have to not scroll after doing the select or you won't be getting the answer you want.