When a user runs `gh stack submit` and an existing PR is discovered for
a branch via `FindPRForBranch`, that PR may have auto-merge enabled.
Auto-merge is incompatible with stacked PRs because the PR would merge
on its own, breaking the stack's base chain.
Previously, the eligibility guard for auto-merge was only in the `link`
command (which blocks such PRs with an error). The `submit` command had
no such check, allowing users to add auto-merge-enabled PRs to a stack
by running `init` followed by `submit`.
This change adds auto-merge detection and automatic disabling in
`submit`'s `ensurePR` function. When an existing PR with auto-merge
enabled is discovered, the CLI disables auto-merge via the
`disablePullRequestAutoMerge` GraphQL mutation and warns the user.
If the disable call fails, submit continues with a warning (non-fatal).
The `link` command retains its stricter behavior of blocking auto-merge
PRs outright, since the user explicitly chose those PRs and can fix
them before retrying.
Changes:
internal/github/github.go:
- Add DisableAutoMerge() method using the
disablePullRequestAutoMerge GraphQL mutation
internal/github/client_interface.go:
- Add DisableAutoMerge(prID string) error to ClientOps interface
internal/github/mock_client.go:
- Add DisableAutoMergeFn field and mock implementation
cmd/submit.go:
- In ensurePR, after discovering an existing PR with auto-merge
enabled, call DisableAutoMerge before proceeding. Warns on
success ("Disabled auto-merge for PR #N (incompatible with
stacked PRs)") and on failure ("failed to disable auto-merge").
cmd/submit_test.go:
- Add TestSubmit_DisablesAutoMergeOnExistingPR: verifies auto-merge
is disabled and warning is shown
- Add TestSubmit_DisableAutoMergeFailure_ContinuesWithWarning:
verifies submit continues even if the disable call fails
- Add TestSubmit_NoAutoMerge_SkipsDisable: verifies DisableAutoMerge
is not called for PRs without auto-merge
The `link` command previously allowed PRs in any state to be added to a
stack, including PRs that had already been merged, were closed, were
sitting in a merge queue, or had auto-merge enabled. Adding such PRs to
a stack is invalid because they have already been or will soon be merged,
which breaks the stacked PR workflow.
Add a new validation phase (Phase 2b) to `runLink` that checks the
eligibility of every existing PR found during lookup, before any new PRs
are created or stack operations are performed. Only open/draft PRs
without auto-merge enabled are eligible. All ineligible PRs are reported
at once with a clear per-PR error message indicating the specific reason
(merged, closed, in merge queue, or auto-merge enabled).
Changes:
internal/github/github.go:
- Add AutoMergeRequest struct and field on PullRequest
- Add IsAutoMergeEnabled() method on *PullRequest
- Update FindPRByNumber and FindPRForBranch GraphQL queries to fetch
the autoMergeRequest field
internal/github/github_test.go:
- Add TestPullRequest_IsAutoMergeEnabled (nil, non-nil, nil receiver)
cmd/link.go:
- Add pr field to resolvedArg to retain full PR data from lookup
- Add validatePREligibility() that rejects merged/closed/queued/
auto-merge-enabled PRs with descriptive error messages
- Wire validation into runLink between PR lookup and stack operations
cmd/link_test.go:
- Add 7 tests covering each disallowed state by PR number and branch
name, plus a multi-invalid-PR reporting test
Audit all 7 GraphQL operations and remove fields that are fetched but
never used in Go code:
- Remove FindAnyPRForBranch: entire function is dead code (zero call sites)
- FindPRForBranch: remove title, state, headRefName, merged (4 fields)
- CreatePR: remove title, state, headRefName, baseRefName, isDraft (5 fields)
- FindPRDetailsForBranch: remove id, title, headRefName, baseRefName,
comments { totalCount } (4 fields + 1 nested object)
- FindPRByNumber: remove title (1 field)
Also remove Title from PullRequest struct, and Title + CommentsCount
from PRDetails struct since they are no longer populated or read.
Total: ~15 unused fields removed across 5 queries, 1 dead query deleted,
and 1 unnecessary nested object (comments) eliminated.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Sameen Karim