Re: git 2.34.0: Behavior of `**` in gitignore is different from previous versions.

Thanks for your follow-up.

I wanted to ignore all files in the "data" folder except ".txt" ones.

As mentioned in the gitignore doc, there should be a difference
between "**" and "**/".

A trailing "/**" matches everything inside. For example, "abc/**" matches all files inside directory "abc", relative to the location of the .gitignore file, with infinite depth.

and,

A slash followed by two consecutive asterisks then a slash matches zero or more directories. For example, "a/**/b" matches "a/b", "a/x/b", "a/x/y/b" and so on.

and also,

It is not possible to re-include a file if a parent directory of that file is excluded.

So, I excluded all files by "data/**", re-included just directories
(at any depth) by "!data/**/" and, re-included ".txt" files (at any
depth) by "!data/**/*.txt".
However, if I wanted to re-include a directory and all of its
contents, I could use something like "!data/data1/**", without
trailing slash.
As I see, there is no separation between "**" and "**/" in the current version.

I think there is another point that the previous behavior test case
should be like this:
test_expect_success 'directories and ** matches' '
    cat >.gitignore <<-\EOF &&
    data/**
    !data/**/
    !data/**/*.txt
    EOF
    git check-ignore file \
        data/file data/data1/file1 data/data1/file1.txt \
        data/data2/file2 data/data2/file2.txt >actual &&
    cat >expect <<-\EOF &&
    data/file
    data/data1/file1
    data/data2/file2
    EOF
    test_cmp expect actual
'
Thanks
Danial


On Fri, Nov 19, 2021 at 1:40 AM Derrick Stolee [off-list ref] wrote:

On 11/18/2021 12:04 PM, Jeff King wrote:

quoted

On Thu, Nov 18, 2021 at 08:11:04PM +0330, Danial Alihosseini wrote:

quoted

What did you do before the bug happened? (Steps to reproduce your issue)
Consider the following project structure
- data
  - data1
    - file1
    - file1.txt
  - data2
    - file2
    - file2.txt
- .gitignore


`.gitignore` is as follows:

data/**
!data/**/
!data/**/*.txt

What did you expect to happen? (Expected behavior)

I expect all files in `data` folder to be ignored except `.txt` files.

What happened instead? (Actual behavior)

`file1` and `file2` are not ignored.
Here is the `check-ignore` output:

$ git check-ignore -v data/data1/file1
.gitignore:2:!/data/**/ data/data1/file1

Thanks for an easy reproduction. It looks like this changed in
f6526728f9 (dir: select directories correctly, 2021-09-24). Author cc'd.

Thanks for the bisect and CC.

quoted

The key thing seems to be that the second line of your .gitignore should
match only directories (because of the trailing slash), but no longer
does.

Doesn't "matching only directories" mean it would match everything
within that directory? (It also means that "data/file" is not matched,
which is still correct.)

My interpretation of these patterns is that everything in data/data1/
and data/data2/ should not be ignored, making it seem like the change
fixed a bug (it definitely changed behavior).

Just for extra clarity, this test currently passes:

test_expect_success 'directories and ** matches' '
        cat >.gitignore <<-\EOF &&
        data/**
        !data/**/
        !data/**/*.txt
        EOF
        git check-ignore file \
                data/file data/data1/file1 data/data1/file1.txt \
                data/data2/file2 data/data2/file2.txt >actual &&
        cat >expect <<-\EOF &&
        data/file
        EOF
        test_cmp expect actual
'

but the previous behavior would have passed this test:

test_expect_success 'directories and ** matches' '
        cat >.gitignore <<-\EOF &&
        data/**
        !data/**/
        !data/**/*.txt
        EOF
        git check-ignore file \
                data/file data/data1/file1.txt \
                data/data2/file2.txt >actual &&
        cat >expect <<-\EOF &&
        data/file
        EOF
        test_cmp expect actual
'

I seek more clarity on this. Specifically: if we match a directory
then should we not also match the contents within?

Thanks,
-Stolee