Putting { on the same line as the method declaration doesn't change the behavior at all.
It does for me. But my indentation is going the other way. I haven't been able to reproduce your unwanted indentation direction yet.
The thing that bothers me is that there are something like 30 million registered developers, and some unknown number of download-only Xcode users. I have seen two people report unwarned right indentation and two people report unwanted left indentation. What are the other millions of people doing? Are our preferences just corrupted or something?
And yet, people seem to be super excited about the new EditorConfig option. I had hoped it would allow users to control indentation settings. But no, it does virtually nothing. Instead of choosing spaces or tabs in Xcode settings, we can create a new file, add it to an Xcode project, and that will specify whether we want to use spaces or tabs. Hallelujah! That's literally all it does.
In my case, I've turned off all indentation options. But this is the one indentation that I can't disable. Since you are going the other way, try turning off your indentation settings.
Topic:
Developer Tools & Services
SubTopic:
Xcode