Copilot instructions

1---
2applyTo: "apps/studio/**"
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5# Studio Testing Review Rules
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7All comments are **advisory**.
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9## Core Principle
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11Push logic out of React components into pure `.utils.ts` functions, then test those functions exhaustively. Only use component tests for complex UI interactions.
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13## When to Comment
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15- PR adds **business logic inline in a component** that could be extracted to a `ComponentName.utils.ts` file next to the component and unit tested at `tests/components/.../ComponentName.utils.test.ts`
16- PR adds a **utility function without test coverage**
17- PR uses **component tests for pure logic** that should be a unit test on a pure function
18- PR adds a **feature used in both self-hosted and platform** without E2E test consideration
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20## Which Test Type to Suggest
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22- **Pure transformation** (parse, format, validate, compute) → extract to `.utils.ts` + unit test with vitest
23- **Complex UI interaction** → component test with `customRender` (or E2E if shared with self-hosted)
24- **E2E tests** should cover both click interactions AND keyboard shortcuts
25- **No tests at all** for non-trivial changes → nudge to add coverage
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27## Reference
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29See `.claude/skills/studio-testing/SKILL.md` for the full testing standard.
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