Resolve path to current file

Question

I have an abbrevation for running git blame on the current file, but it fails in the presence of symlinks.

Here's the abbreviation

cnoreabbrev gbl ! ( cd %:h ; exec git blame %:t )

My .vimrc is a symlink to ~/config/vim/vimrc.

$ ls -l .vimrc | cut -d' ' -f8-
16 Jan 29 20:54 .vimrc -> config/vim/vimrc

When I open my .vimrc from the home directory, it doesn't show me the git blame because I'm not inside the project root.

Is there something kind of like realpath(3) that I can use from the vim side to get a canonical path to the current file? I'd like to replace %:h with a canonical path to the directory containing the current file and %:t the corresponding file name.

Answer 1

You could try this abbreviation:

cnoreabbrev <expr> gbl getcmdtype() == ':' && getcmdpos() == 4 ? '! ( cd '.fnamemodify(resolve(expand('%')), ':h').' ; git blame '.fnamemodify(resolve(expand('%')), ':t').' )' : 'gbl'

---

It uses the resolve() function to resolve the symbolic links, and fnamemodify() to extract the head of the path as well as the filename component:

fnamemodify(resolve(expand('%')), ':h')    → head of the path
fnamemodify(resolve(expand('%')), ':t')    → tail of the path

Also, it makes sure that your abbreviation is only expanded on a regular Ex command line (getcmdtype() == ':'), and only if you're at the very beginning of the line (getcmdpos() == 4).

If you wanted the abbreviation to be expanded anywhere on the command line, you could remove the 2nd condition:

cnoreabbrev <expr> gbl getcmdtype() == ':' ? '! ( cd '.fnamemodify(resolve(expand('%')), ':h').' ; git blame '.fnamemodify(resolve(expand('%')), ':t').' )' : 'gbl'