In git there is a command git commit --amend
to edit your last commit message. I was looking for this type of functionality in pycharm and can\'t seem to find it. I
Rather than using VCS "Commit Changes ..." and amending, I found it more intuitive to show the Git Log, and from the context menu on the previous commit, do a "Reset Current Branch to Here". In the popup, select "Soft" reset, which doesn't change files and does stage changes for commit.
That seems more like how an undo should work, putting the project back in the state it was before I mistakenly issued the commit with the wrong message.