This is quite similar to gitignore. If a pattern is suffixed by an
exclamation mark and match a file that was previously matched by a
regular pattern, the match is cancelled. Notably, this can be used
with `--exclude-file` to cancel the exclusion of some files.
Like for gitignore, once a directory is excluded, it is not possible
to include files inside the directory. For example, a user wanting to
only keep `*.c` in some directory should not use:
~/work
!~/work/*.c
But:
~/work/*
!~/work/*.c
I didn't write documentation or changelog entry. I would like to get
feedback if this is the right approach for excluding/including files
at will for backups. I use something like this as an exclude file to
backup my home:
$HOME/**/*
!$HOME/Documents
!$HOME/code
!$HOME/.emacs.d
!$HOME/games
# [...]
node_modules
*~
*.o
*.lo
*.pyc
# [...]
$HOME/code/linux/*
!$HOME/code/linux/.git
# [...]
There are some limitations for this change:
- Patterns are not mixed accross methods: patterns from file are
handled first and if a file is excluded with this method, it's not
possible to reinclude it with `--exclude !something`.
- Patterns starting with `!` are now interpreted as a negative
pattern. I don't think anyone was relying on that.
- The whole list of patterns is walked for each match. We may
optimize later by exiting early if we know no pattern is starting
with `!`.
Fix #233
Match/ChildMatch accept a ** pattern which is not noted in the doc
string, nor do any of the docs or tests specify whether the match is
greedy (i.e., can 'foo/**/bar' match paths with additional intermediate
bar directories?).
Add a note to the doc string and add test cases for greedy matches.
This improves restore performance by several orders of magniture by not
going through the whole tree recursively when we can anticipate that no
match will ever occur.