Allow symlinks in gh-pages

[timwsuqld]

For a strange use case, we have a gh-pages directory that requires a symlink. The symlink is fine in the build directory, but never comes across when using gh-pages.

In my quick read of the code, I can't see anything obvious that would allow us to bring symlinks across. It would be great if this could be supported

[davisp]

os.walk doesn't follow symlinks by default. If you want to add a PR to make that an option I'd be willing to add that.

[davisp]

I had to reorganize some other things and this became an easy add so ghp-import now supports passing -l on the command line to follow symlinks out of your docs directory.

[dhimmel]

I had to reorganize some other things and this became an easy add

For reference, the commit was cb1dd9a.

ghp-import now supports passing -l on the command line to follow symlinks out of your docs directory.

This is not a great description of the current behavior of --follow-links. Neither is the help message:

https://github.com/davisp/ghp-import/blob/0e2045e750569f67cbcd96e7e53dbfc865df747e/ghp_import.py#L215

Or the README mention:

The -l option will cause the import to follow symlinks for users that have odd configurations that include symlinking outside of their documentation directory.

Here is where --follow-links has an effect in the code:

https://github.com/davisp/ghp-import/blob/0e2045e750569f67cbcd96e7e53dbfc865df747e/ghp_import.py#L174-L179

Specifically, it is passed through to os.walk, whose documentation states:

By default, walk() will not walk down into symbolic links that resolve to directories. Set followlinks to True to visit directories pointed to by symlinks, on systems that support them.
Note: Be aware that setting followlinks to True can lead to infinite recursion if a link points to a parent directory of itself. walk() does not keep track of the directories it visited already.

So from reading this, I believe the behavior of ghp-import without --follow-links is to follow symlinks for files but not directories. With --follow-links, the behavior is follow symlinks for files and directories.

I'm going to open another issue regarding symlinks, but wanted to understand the current behavior first, hence posting to this issue.