Fix possible panic

[Gusted]

• The code will get the first and second character link[{0,1]]. However in a rare case the link could have 1 character and thus the link[1] will create a panic.

[wxiaoguang]

I agree about this fix.

One more thing, if some fallbackImage is "/", I think we should fix that fallbackImage to a real correct fallback image.

[Gusted]

One more thing, if some fallbackImage is "/", I think we should fix that fallbackImage to a real correct fallback image.

That seems good to me, what do you suggest that the fallback of the fallback should be?

[wxiaoguang]

One more thing, if some fallbackImage is "/", I think we should fix that fallbackImage to a real correct fallback image.

That seems good to me, what do you suggest that the fallback of the fallback should be?

I haven't read about the code. I think the "correct fallback images" should depend on the avatar owners.

For users, the default avatar is /assets/img/avatar_default.png (a Gitea logo), if a users didn't set their avatar, then the default one is shown.

For repositories, IIRC: if no avatar was set, then no avatar should be shown, so I think here we have a deeper problem: we were trying to show an incorrect avatar for a repository without avatar.

[Gusted]

so I think here we have a deeper problem: we were trying to show an incorrect avatar for a repository without avatar.

Just to note - that when this happen the admin of the gitea server was doing this on purpose as if it was explicitly set to the fallbackImage mode whereby that setting was set to a value of "/" of some sort.

[wxiaoguang]

OK, then I think something like this would be enough (and more simple):

func (repo *Repository) avatarLink(e db.Engine) string {
	link := repo.relAvatarLink(e)
	// we only prepend our AppURL to our known (relative, internal) avatar link to get an absolute URL
	if strings.HasPrefix(link, "/") && !strings.HasPrefix(link, "//") {
		return setting.AppURL + strings.TrimPrefix(link, setting.AppSubURL)[1:]
	}
	// otherwise, return the link as it is
	return link
}