music_library/backlog/completed/ml-195 - Add-Credo-check-for-LiveComponent-toast-helper-usage.md

id, title, status, assignee, created_date, updated_date, labels, dependencies, priority, ordinal

id	title	status	assignee	created_date	updated_date	labels	dependencies	priority	ordinal
ML-195	Add Credo check for LiveComponent toast helper usage	Done	pi	2026-05-21 06:57	2026-05-21 07:05			medium	38000

Description

Add a custom Credo check that flags calls to put_toast/3 from LiveComponent modules so contributors use the LiveComponent-safe put_toast!/2 helper instead.

Acceptance Criteria

• #1 Credo fails when a LiveComponent module calls put_toast/3.
• #2 Credo does not flag allowed put_toast!/2 calls inside LiveComponents.
• #3 Credo does not flag put_toast/3 usage outside LiveComponent modules.
• #4 Automated tests cover the new check behavior.

Implementation Plan

1. Review Credo configuration and any existing custom checks/tests to match project conventions.
2. Add a custom Credo check that detects modules using use MusicLibraryWeb, :live_component and reports calls to put_toast/3, including pipeline form when applicable.
3. Register the check in Credo config so mix credo runs it.
4. Add focused tests for disallowed LiveComponent usage, allowed put_toast!/2, and allowed non-LiveComponent put_toast/3 usage.
5. Run the relevant test file and Credo check to validate behavior.

Implementation Notes

Implemented MusicLibrary.Credo.NoLiveComponentPutToast, registered it in .credo.exs, and updated existing RecordForm LiveComponent toast calls to put_toast!/2 so the new rule can be enabled cleanly. Validation: mix test test/music_library/credo/no_live_component_put_toast_test.exs; mix test test/music_library_web/live/collection_live/show_test.exs --max-failures 1; mix test test/music_library_web/live/collection_live/index_test.exs --max-failures 1; mix credo --strict.

Final Summary

Summary:

• Added MusicLibrary.Credo.NoLiveComponentPutToast, a custom Credo warning that detects put_toast/3 calls inside LiveComponent modules and covers direct, piped, qualified, and captured call forms.
• Registered the custom check in .credo.exs.
• Cleaned up existing RecordForm LiveComponent toast usage by switching to put_toast!/2 before returning/pushing patches.
• Added focused Credo check tests for disallowed LiveComponent usage and allowed LiveComponent/non-LiveComponent cases.

Validation:

• mix test test/music_library/credo/no_live_component_put_toast_test.exs
• mix test test/music_library_web/live/collection_live/show_test.exs --max-failures 1
• mix test test/music_library_web/live/collection_live/index_test.exs --max-failures 1
• mix credo --strict

Docs:

• No documentation update needed; docs/project-conventions.md already documents the LiveView vs LiveComponent toast helper rule.