How can I ignore a specific file in sub folder by using .gitignore?

Question

There is a big .exe file in a subfolder in my project, my fold tree is like:

.
├── folder1
│   └── theBigFileThatIWantToIgnore.exe
├── folder2
│   ├── fileA
│   └── fileB
│———.gitignore
└── ...

And at first, I didn't mention that this "theBigFileThatIWantToIgnore.exe" is larger than 100MB so git bash noticed me it.

then, I tried to ignore this .exe file by using .gitignore, my .gitignore file is:

/folder1/theBigFileThatIWantToIgnore.exe

and before I git push again, I used git rm -r --cached . , but it is useless...

HELP MEEEEE!thanks!

Answer 1

This should ignore it:

cd /path/to/repo
echo "/folder1/theBigFileThatIWantToIgnore.exe">>.gitignore
git rm --cached folder1/theBigFileThatIWantToIgnore.exe
git check-ignore -v -- folder1/theBigFileThatIWantToIgnore.exe
# you should see a .gitignore rule

However, that will allow you to create a new commit without that exe.
That will not, however, remove the exe from the past comimts/history of the repository, which will remain huge as a result.

To truly cleanup the repository, install git filter-repo, and use a path-based filtering

git filter-repo  --path folder1/theBigFileThatIWantToIgnore.exe --invert-paths

You will need to force push the result though, so make sure any collaborator on that repository is aware of that change (history rewrite).