[alexcarpenter]

Description

Adds a mosaic/no-render-clock lint rule that flags Date.now() and new Date() when they run during render: in a component or hook body, or in a useState, useMemo or useRef initializer. The message points to useNow, so these reads go through MosaicNowProvider and the server and client agree. Reads in effects, event handlers, useCallback and machine actions are still allowed, and so is a parsed date like new Date(value).

• src/hooks/use-now.ts and src/mosaic-provider.tsx are exempt because they own the clock. Test files are ignored.
• Stacked on fix(mosaic): count resend cooldowns down from the clock #10619. On main, the only hit is reverification's countdown, which that PR moves onto useNow.

Checklist

• pnpm test runs as expected.
• pnpm build runs as expected.
• (If applicable) JSDoc comments have been added or updated for any package exports
• (If applicable) Documentation has been updated

Type of change

• 🐛 Bug fix
• 🌟 New feature
• 🔨 Breaking change
• 📖 Refactoring / dependency upgrade / documentation
• other: lint rule

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🦋 Changeset detected

Latest commit: bc07817

The changes in this PR will be included in the next version bump.

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[blacksmith-sh]

Render-time clock reads are flagged

All six render-time reads (component body, hook body, useState, useMemo, useRef, forwardRef) are flagged with the useNow message after; none were flagged by this rule before.

_Merge-base

_{This PR bc07817a}

Also checked · 2 match

Non-render reads still allowed
Clock owners and tests exempt

_{Proof on bc07817a · Did Proof get it right? Yes · No}

View full Proof report