refactor(cli): model stack as a native clap subcommand tree

[JulianMaurin]

stack was the last vestige of the Python port: a Stack(ShimmedArgs)
catch-all (trailing_var_arg) whose raw argv was re-parsed by a
hand-written dispatch_stack, with the subcommand token consumed as
the program name of a secondary clap parse. No Python remains, so this
was pure dead scaffolding — and it cost real UX:

• mergify stack --help printed Usage: stack <COMMAND> with no
  subcommand descriptions; mergify stack new --help printed
  Usage: new ….
• the global --debug flag was rejected on stack subcommands.
• cli_schema.rs had to graft the stack subcommands in by hand
  (a third subcommand list that could silently drift).

Model stack as a normal clap subcommand: Stack(StackArgs) with
#[command(subcommand)] command: StackSubcommand, one variant per
subcommand wrapping the existing StackXxxCli struct (now
derive(Args) instead of derive(Parser)). Help text moves onto the
variants. dispatch_from_parsed matches the variants and builds the
same NativeCommand as before (squash keeps its fallible TryFrom →
exit 2). dispatch_stack, StackProbeCli, StackProbeSubcommand,
ShimmedArgs, and the cli_schema graft are deleted — the schema now
comes from a uniform clap-tree walk. Net -245 lines.

mergify stack --help now lists all 16 subcommands with descriptions,
stack <sub> --help shows the full mergify stack <sub> usage,
--debug is accepted, and the published schema can't drift from the
command tree.

Co-Authored-By: Claude Opus 4.8 (1M context) noreply@anthropic.com

[mergify]

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[JulianMaurin]

This pull request is part of a Mergify stack:

#	Pull Request	Link
1	refactor(cli): model stack as a native clap subcommand tree	#1652	👈
2	refactor(core): preserve error sources and print the cause chain	#1653
3	fix(self-update): exit with the GitHub-API code and retry transients	#1654
4	feat(http): honor GitHub rate limits and bound connect time	#1655
5	feat(cli): add a global --color flag and fix queue-show glyphs	#1656
6	feat(cli): add a -v/-vv verbosity ladder backed by tracing	#1657
7	feat(cli): generate shell completions and a man page	#1658
8	test: golden-snapshot the CLI surface and guard schema drift	#1659
9	refactor: dedupe the GIT_SEQUENCE_EDITOR lookup and drop port cruft	#1660
10	docs(agents): rewrite AGENTS.md for the Rust workspace	#1661
11	fix(cli): render stack-squash validation errors via clap	#1671

[JulianMaurin]

Revision history

#	Type	Changes	Reason	Date
1	initial	8738916		2026-06-19 07:52 UTC
2	rebase	8738916 → 6ba7b33 (rebase only)		2026-06-19 07:52 UTC
3	content	6ba7b33 → 6dbc5f9		2026-06-19 16:51 UTC

[mergify]

@JulianMaurin this pull request is now in conflict 😩

[mergify]

A predecessor in this stack was just merged, but I couldn't auto-rebase this PR: there's a conflict that needs human resolution.

Conflict in: .github/workflows/ci.yaml (replayed onto 1e114401).

Resolve by rebasing this branch onto the latest base and pushing.

[Copilot]

Pull request overview

This PR refactors the stack command to be a first-class native clap subcommand tree instead of a trailing-argv “shim” that re-parsed arguments in a second pass. This removes dead scaffolding, improves --help/usage output, and ensures the published CLI schema is generated from a single uniform clap tree (preventing drift).

Changes:

• Replaces the Stack(ShimmedArgs) + dispatch_stack secondary parsing with Stack(StackArgs) and a StackSubcommand enum wired directly into the main clap parse/dispatch.
• Moves stack subcommand help text onto StackSubcommand variants; converts Stack*Cli types from derive(Parser) to derive(Args).
• Simplifies CLI schema generation by deleting the special-case grafting of stack subcommands and relying on the normal clap tree walk.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
crates/mergify-cli/src/main.rs	Refactors stack into a native clap subcommand tree and updates dispatch/help plumbing accordingly.
crates/mergify-cli/src/cli_schema.rs	Removes the stack-specific schema graft; schema now comes entirely from the clap command tree.

---

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[mergify]

Queued — the merge queue status continues in this comment ↓.

[mergify]

Merge Queue Status

• ✅ Entered queue — 2026-06-22 12:49 UTC · Rule: default
• ✅ Checks skipped · PR is already up-to-date
• ✅ Merged — 2026-06-22 12:49 UTC · at 6dbc5f9b72145ce3a895a3170a47b312ffea36af · squash

This pull request spent 21 seconds in the queue, including 5 seconds running CI.

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