Can I force python-mode's (or syntastic's) error flags over the line number columns?

Question

When syntastic or python-mode finds an error in my python file, they create a new column at the left-hand side of the window with flags at the lines where the errors are:

This new column not only causes buffer to shift (which I find disruptive), but also prevents my 80-column-width lines from fitting nicely in the window.

Is there a way to have these flags placed in the line number column?

For longer files, I understand these flags would probably replace overwrite the numbers in the lines they appear. I wouldn't have a problem with that.

Answer 1

No, this unfortunately isn't possible. The signs column is separate, and always with a width of two cells. From :help signs:

When signs are defined for a file, Vim will automatically add a column of two characters to display them in. When the last sign is unplaced the column disappears again.

You could only configure Syntastic to not use signs at all (via let g:syntastic_enable_signs = 0, thanks @lcd047!).

Answer 2

You can achieve this by adding set signcolumn=number to your .vimrc.

Showing signs in the number column was added in v8.1.1564.