On my computer, my default git user is for my work account. I was working on a personal project, pushed it to GitHub, and didn’t realize until after that I had been commiting with my work username/email. Some Googling turned up that you can rewrite history from one email/username to another:
\ngit filter-branch --env-filter '\nOLD_EMAIL=\"your-old-email@example.com\"\nCORRECT_NAME=\"Your Correct Name\"\nCORRECT_EMAIL=\"your-correct-email@example.com\"\nif [ \"$GIT_COMMITTER_EMAIL\" = \"$OLD_EMAIL\" ]\nthen\n export GIT_COMMITTER_NAME=\"$CORRECT_NAME\"\n export GIT_COMMITTER_EMAIL=\"$CORRECT_EMAIL\"\nfi\nif [ \"$GIT_AUTHOR_EMAIL\" = \"$OLD_EMAIL\" ]\nthen\n export GIT_AUTHOR_NAME=\"$CORRECT_NAME\"\n export GIT_AUTHOR_EMAIL=\"$CORRECT_EMAIL\"\nfi\n' --tag-name-filter cat -- --branches --tagsI got a nasty warning, but after a few seconds it proceeded with the rewrite and the world didn’t seem to end. I guess I could have tried the suggested alternative, but I only had a few commits and the rewrite seemed mostly innocuous.
\nWARNING: git-filter-branch has a glut of gotchas generating mangled history\n rewrites. Hit Ctrl-C before proceeding to abort, then use an\n alternative filtering tool such as 'git filter-repo'\n (https://github.com/newren/git-filter-repo/) instead. See the\n filter-branch manual page for more details; to squelch this warning,\n set FILTER_BRANCH_SQUELCH_WARNING=1.A git push --force and my repo commits were updated with my personal email.