Open Radar

 
Summary:
Xcode sometimes suddenly does not start drags anymore in the text editor. Xcode needs to be quit (losing  file history and undo history in the window, and generally interrupting work) to restore functioning drag starts.

Steps to Reproduce:
Use Xcode for a while. In the evening when work ends, put your Mac to sleep (I usually Ctrl-Shift-Eject to engage the screen lock. It is set to go to sleep after 10 mins, wake for network access is on, so not sure if it actually hard-sleeps or stays awake with locked screen). Use Xcode every day for ~8 hours.

Every few days, Xcode will stop starting drags.

At that point, E.g. I triple-click a line in my source code and try to drag it up to re-arrange the lines in a function.

Expected Results:
Xcode should start a drag of the selection (a whole line, though other drags don't seem to work anymore either), letting me move the line elsewhere, as it usually does.

Actual Results:
No matter whether I drag horizontally or vertically, and how long I hold the mouse down before commencing to move, or whether I click on a letter (even only on black pixels) or in whitespace at the start of the line, it will immediately remove the selection and place the insertion mark there. The cursor does not change into an arrow cursor either.

Regression:
This has been happening for a few Xcode versions now, I'm not sure when it actually started, but I think it's new with the 6.x series, probably even not until 6.1.

Notes:
I have line numbers in the gutter turned off, font set to Monaco, auto-indent off. I think that's about my deviation from the standard settings in the editor.