I figured out I can show old versions of a file using \'git log filename\' to show the commits, and then use \'git show commit-id:filename\' for the old version. But it just
Using the following Vim command, one can view a previous version of a file without having to cleanup anything afterward.
git show commit-id:filename | vim - -n
Explanation: The dash argument of the vim command makes vim load whatever comes in from standard input. The -n option suppresses the creation of swap files.