How do I tell Git to ignore everything except a subdirectory?

Question

This ignores root files & root directories, then un-ignores the root bin directory:

/*
/*/
!/bin/

This way you get all of the bin directory, including subdirectories and their files.

Here how to ignore everything exept one directory "MY_SUPER_DUPER_TEMPLATE_directory" in some directory

Structure: /bitrix/templates/MY_SUPER_DUPER_TEMPLATE_directory

/*
!/bitrix
/bitrix/*
!/bitrix/templates
/bitrix/templates/*
!/bitrix/templates/MY_SUPER_DUPER_TEMPLATE_directory
*.DS_Store
*.gitignore

You must exclude everything on the way to the destinations, but you must include the destinations:

Note: This is an exclusion file (i.e. .gitignore) so the logic is inverted. Ignore all, except the tsp directory, ignore all in tsp directory, except the src directory...

/*
!/tsp
/tsp/*
!/tsp/src
/tsp/src/*
!/tsp/src/*.h
!/tsp/src/*.cpp
!/tsp/src/data.txt
!/.gitignore

The only issue you have is that the bin directory itself is not matched by the bin/* pattern so git isn't even look in the bin directory.

There are two solutions that spring to mind.

.gitignore :

*
!/bin/
!bin/*

or

.gitignore :

*
!/bin/

bin/.gitignore :

!*

I prefer the second solution as the first solution won't stop ignoring files in the bin directories that are in subdirectories that aren't called bin. This may or may not matter in your situation.

From the official git doc, one of the examples says:

Example to exclude everything except a specific directory foo/bar (note the /* - without the slash, the wildcard would also exclude everything within foo/bar):

$ cat .gitignore
# exclude everything except directory foo/bar
/*
!/foo
/foo/*
!/foo/bar

For an explanation about the leading slash: When to use leading slash in gitignore.

Try following in latest GIT version.

*
!*/
!/path/to/your/dir/**