Support non-main default branch via the branches map (+ demotion guard) - #81
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This reverts commit a0a6784.
Reimplements non-main default branch support (previously #57's provider `rename`, reverted in the prior commit) by injecting the desired default branch into the module's branches map so it is created as a real github_branch resource, then pointed at by github_branch_default. - vendored module: when default_branch is non-main (and auto_init is set, and it is not already listed in var.branches), append it to branches_map so github_branch creates it off the auto-init "main". - root module: add an import block for github_branch.branch[default_branch] scoped to generated_repos with a non-main default, so existing repos import the branch instead of failing to create one that already exists.
Switching a repository's default branch from a non-main branch (e.g. master) back to main cannot be applied directly: Terraform destroys the managed github_branch before demoting the default, and GitHub rejects deleting a repository's default branch (422). The plan succeeds but the apply fails and keeps failing until state is reconciled. - docs/switching-default-branch-to-main.md: runbook — state rm the branch first (forgets it without deleting), then flip the YAML to main. - tf-plan.yaml (Report result): detect a github_branch.branch deletion in the plan summary, prepend a warning linking the runbook to the PR comment, and set the check run to action_required so a required check blocks the merge until the runbook is followed. Self-clears once the branch is state-rm'd.
dev-milos
approved these changes
Sep 23, 2026
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LGTM |
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Lets a repo's default branch (e.g.
master) be set declaratively from YAML, including on existing repos — replacing #57'srename(reverted here), which was create-only and forced hand-creating the branch + a PR for existing repos.Changes
maindefault_branchintobranches_mapsogithub_branchcreates it off the auto-initmain, thengithub_branch_defaultpoints at it.import {}block for the default branch (scoped toimporter_tmp_dir/) so existing repos import it instead of colliding.master → main, which otherwise fails apply with422 Cannot delete the default branch): runbookdocs/switching-default-branch-to-main.md(state rmthe branch first), and a tf-plan check that warns + sets the checkaction_requiredto block merge until the runbook is followed.Rollout note: on a workspace with existing non-
main-default repos, import their default branches into state first, or the first apply fails (422/404).Verified end-to-end on the dev workspace (all creation paths + a real demotion PR).