react-doctor/prefer-motion-transform-property

Prefer a complete Motion transform string only when profiling shows acceleration is crucial and transform ownership can remain correct

Validation prompt

Confirm the detector match and collect the required evidence before deciding whether an edit is warranted.

For react-doctor/prefer-motion-transform-property, this opt-in detector reads static Motion animation props other than initial. It reports x, y, scale, or rotate when the same object lacks a direct transform property. It does not prove main-thread contention, hardware acceleration, or complete transform ownership. Audit drag, layout projection, gestures, variants, transformTemplate, CSS, and other animation owners. Motion documents that individual transforms use CSS variables and are not hardware-accelerated, but a full transform string is warranted only when acceleration is crucial. Require a representative production trace and a complete transform-owner audit before confirming. The Before example is representative, not exhaustive.

Evidence boundary

The diagnostic proves only that the detector’s modeled source pattern matched. It does not prove runtime impact, product intent, rendered failure, or that one remediation is correct.

Establish the environment, repository policy, exceptions, and required rendered or runtime evidence before deciding the occurrence.

The design tag controls activation and discovery. It does not determine the rule’s proof class.

Record one outcome:

• Confirmed failure: The required evidence establishes the violation.
• Rejected: A documented exception or false-positive predicate applies.
• Needs evidence: Named evidence can still be collected.
• Unavailable: Required evidence cannot be collected in this run.
• Waived with evidence: An authorized, scoped exception applies to an established failure.
• Observation: The review records an optional tradeoff without claiming a defect.

A waiver records its scope, authority, evidence, and review condition. It is not a pass or false positive.

Default severity is registry metadata. Use the occurrence’s JSON severity after repository configuration when ordering real findings.

Review a candidate correction

Apply this candidate correction only after the required evidence confirms the risk.

Reported pattern

import { motion } from "motion/react";

const Demo = () => (
  <motion.div
    animate={{ x: 120, scale: 1.1 }}
    transition={{ type: "tween", duration: 0.3 }}
  />
);

Candidate corrected pattern

import { motion } from "motion/react";

const Demo = () => (
  <motion.div
    animate={{ transform: "translateX(120px) scale(1.1)" }}
    transition={{ type: "tween", duration: 0.3 }}
  />
);

Fix prompt

Apply this candidate correction only after the required evidence confirms the risk.

Use one complete transform string only when a trace shows material main-thread contention. First confirm that no other transform owner must compose with it. Preserve every value, unit, operation order, transition type, duration, easing, delay, interruption, and reduced-motion behavior. Use a dedicated wrapper when independent transform owners must coexist. Re-profile the same interaction after the change; do not rewrite healthy Motion code based on syntax alone. See https://motion.dev/docs/performance

Repository-wide copy prompt

Use this repository-wide prompt only after validating each occurrence. For one occurrence, use the guidance above.

import { motion } from "motion/react";

const Demo = () => (
  <motion.div
    animate={{ x: 120, scale: 1.1 }}
    transition={{ type: "tween", duration: 0.3 }}
  />
);

import { motion } from "motion/react";

const Demo = () => (
  <motion.div
    animate={{ transform: "translateX(120px) scale(1.1)" }}
    transition={{ type: "tween", duration: 0.3 }}
  />
);