On 8 Aug 2016, at 18:53, Curt Sellmer wrote:

1. When I select a directory in the file browser and the selected directory
is not open (ie. the triangle is pointing to the right) and press ^⌘N the
file is created not in the selected directory but as a sibling to the
selected directory. Perhaps this is by design?

The rationale is that you can have a directory with only other directories, if we always created inside the selected item, the user would have to take extra steps to select the parent (or deselect if parent is the file browser’s root).

This is also relevant when using copy/paste in the file browser (which use the same logic).

3. When I select a directory in the file browser and press ⌥⌘N, (regardless
of whether the directory is open or closed) I always get an untitled
document with type 'text.plain'. When I subsequently save the file it
correctly goes into the directory that was selected.
- I'm guessing that with ⌥⌘N the file type is not being assigned because
the untitled doc does not yet actually exist in the directory.

Correct, in that New Tab (⌥⌘N) does not reference the file browser. But I can try to make it do it, though it would fall victim to the same logic about needing to have the selected folder expanded.

I may revise the thing about expanded folder, but it introduces some code complexity because then we ought to expand the folder when creating a new file, and folder content is loaded asynchronously…