a5f3515ad8
Something dumb that we're currently doing is expecting list items to define an ID method which returns a string. We use that when copying items to clipboard with ctrl+o and when getting a ref name for diffing. This commit gets us a little deeper into that hole by explicitly requiring list items to implement that method so that we can easily use the new helper functions in list_controller_trait.go. In future we need to just remove the whole ID thing entirely but I'm too lazy to do that right now.
FileTree Package
This package handles the representation of file trees. There are two ways to render files: one is to render them flat, so something like this:
dir1/file1
dir1/file2
file3
And the other is to render them as a tree
dir1/
file1
file2
file3
Internally we represent each of the above as a tree, but with the flat approach there's just a single root node and every path is a direct child of that root. Viewing in 'tree' mode (as opposed to 'flat' mode) allows for collapsing and expanding directories, and lets you perform actions on directories e.g. staging a whole directory. But it takes up more vertical space and sometimes you just want to have a flat view where you can go flick through your files one by one to see the diff.
This package is not concerned about rendering the tree: only representing its internal state.