sg: Add `migration rewrite` command (!39851) · Merge requests · Administrator / sourcegraph · GitLab

Administrator requested to merge ef/migration-rewrite into main Aug 03, 2022

Created by: efritz

Partial fix to https://github.com/sourcegraph/sourcegraph/issues/39863. This PR adds an sg migration rewrite command that resets the migrations on-disk of your clone to the canonical version at the given git revision.

Test plan

Tested by hand locally.