E14 · F11 · SP-010 — Research for F11: folder layouts and test placement

Find, read and record what is common practice for laying out a TypeScript library and its tests, before EN-022 moves any file (ADR-0020, research protocol §8).

Acceptance criteria

• Given the question of test placement, when the spike ends, then the practices found (tests next to their module, or in a separate tree) are compared with their sources, against this project's rules: one export per file (ADR-0019), barrels (ADR-0012), the 100 % coverage of src/.
• Given src/model/ (50 modules) and playground/ (80 modules), when the spike ends, then a layout by subfolder is proposed, with the limit of files per folder and the ESLint rules it touches (layers, barrels, canonical paths).
• Given the proposal, when the spike ends, then the Product Owner chooses, and the choice is an ADR.

Questions

• Where do the tools this project uses expect tests (Vitest's default include, TypeDoc's exclusions), and what do their docs advise?
• What do recognized guides advise for a library's folders: by layer, by feature, by shape kind?
• Which layout keeps import paths short and the layer rules (import-x/no-restricted-paths) simple?

Tasks

One task = one commit, referenced as SP-010.Tn.

• T1 — Read the sources (library first), record them (2 h)
• T2 — Layout proposal with a table of moves, research note, questions for the Product Owner (2 h)