Extract from #32786
`git diff a..b` is equal to `git diff a b` which is different from `git
diff a...b`. For pull request, we should always
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
This module is merged from https://github.com/go-gitea/git which is a Go module to access Git through shell commands. Now it's a part of gitea's main repository for easier pull request.