fix: replace React.createElement with jsx runtime

[stipsan]

Description

Before the JSX transform were introduced it didn't really matter if you called React.createElement directly, or if you used JSX.
With

export default function Component(props) {
  const {icon: Icon} = props

  return <Icon />
}

as input, you got

export default function Component(props) {
  var Icon = props.icon;
  return /*#__PURE__*/ React.createElement(Icon, null);
}

as output. In that world you might as well call it directly, as it's functionally equivalent:

import {createElement} from 'react'

export default function Component(props) {
  return createElement(props.icon)
}

Since then the entire ecosystem has moved to the jsx transform, that includes our vite when using sanity dev|build|deploy, as well as publishing libraries with @sanity/pkg-utils, and most other build tooling like Parcel, tsup etc etc.

With the new transform it's not just a new function being used, it's from a different, standalone export, and its function argument semantics are different:

import { jsx as _jsx } from "react/jsx-runtime";
export default function Component(props) {
  var Icon = props.icon;
  return /*#__PURE__*/ _jsx(Icon, {});
}

On top of that, React 19 introduces new features that are only available if the jsx-runtime transform is used, which isn't supported with createElement.
For example using ref as a prop, instead of using React.forwardRef, requires it:

// React 18 requires a wrapper in function components to forward refs to the dom node
const LoadingIcon = React.forwardRef(
  function(props, ref) {
    return <svg ref={ref} />
  }
)

// React 19 supports ref as a prop
function LoadingIcon(props) {
  return <svg ref={props.ref} />
}

The React 19 <LoadingIcon /> only works if the JSX transform is used (repl):

export default function Component(props) {
  const {icon: Icon} = props
  const ref = useRef()

  return <Icon ref={ref} />
}

// Called as <Component icon={LoadingIcon} />

When using createElement it fails (repl):

import {createElement, useRef} from 'react'

export default function Component(props) {
  const ref = useRef()

  // Due to `createElement` being used, the `ref` won't be set since `LoadingIcon` isn't wrapped in `React.forwardRef`
  return createElement(props.icon, {ref})
}

What to review

Is the linter rule addition that blocks React.createElement clear enough?

Testing

If tests pass we should be good.

Notes for release

Replaced React.createElement calls in internals with the JSX runtime, unlocking the React 19 performance improvements to JSX, as well as the ability to use ref as a prop instead of React.forwardRef wrappers.

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
page-building-studio	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 13, 2024 5:33pm
performance-studio	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 13, 2024 5:33pm
test-next-studio	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 13, 2024 5:33pm
test-studio	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 13, 2024 5:33pm

1 Skipped Deployment

Name	Status	Preview	Comments	Updated (UTC)
studio-workshop	⬜️ Ignored (Inspect)			Dec 13, 2024 5:33pm

[github-actions]

No changes to documentation

[github-actions]

Component Testing Report Updated Dec 13, 2024 5:41 PM (UTC)

❌ Failed Tests (6) -- expand for details

File	Status	Duration	Passed	Skipped	Failed
comments/CommentInput.spec.tsx	✅ Passed (Inspect)	1m 13s	15	0	0
formBuilder/ArrayInput.spec.tsx	✅ Passed (Inspect)	14s	3	0	0
formBuilder/inputs/PortableText/Annotations.spec.tsx	✅ Passed (Inspect)	41s	6	0	0
formBuilder/inputs/PortableText/copyPaste/CopyPaste.spec.tsx	✅ Passed (Inspect)	57s	11	7	0
formBuilder/inputs/PortableText/copyPaste/CopyPasteFields.spec.tsx	✅ Passed (Inspect)	0s	0	12	0
formBuilder/inputs/PortableText/Decorators.spec.tsx	✅ Passed (Inspect)	29s	6	0	0
formBuilder/inputs/PortableText/DisableFocusAndUnset.spec.tsx	✅ Passed (Inspect)	16s	3	0	0
formBuilder/inputs/PortableText/DragAndDrop.spec.tsx	❌ Failed (Inspect)	4m 27s	0	0	6
formBuilder/inputs/PortableText/FocusTracking.spec.tsx	✅ Passed (Inspect)	1m 14s	15	0	0
formBuilder/inputs/PortableText/Input.spec.tsx	✅ Passed (Inspect)	3m 0s	21	0	0
formBuilder/inputs/PortableText/ObjectBlock.spec.tsx	✅ Passed (Inspect)	1m 49s	18	0	0
formBuilder/inputs/PortableText/PresenceCursors.spec.tsx	✅ Passed (Inspect)	14s	3	9	0
formBuilder/inputs/PortableText/RangeDecoration.spec.tsx	✅ Passed (Inspect)	42s	9	0	0
formBuilder/inputs/PortableText/Styles.spec.tsx	✅ Passed (Inspect)	29s	6	0	0
formBuilder/inputs/PortableText/Toolbar.spec.tsx	✅ Passed (Inspect)	1m 53s	21	0	0
formBuilder/tree-editing/TreeEditing.spec.tsx	✅ Passed (Inspect)	0s	0	3	0
formBuilder/tree-editing/TreeEditingNestedObjects.spec.tsx	✅ Passed (Inspect)	0s	0	3	0

[github-actions]

⚡️ Editor Performance Report

Updated Fri, 13 Dec 2024 17:45:50 GMT

Benchmark	reference latency of sanity@latest	experiment latency of this branch	Δ (%) latency difference
article (title)	26.3 efps (38ms)	25.6 efps (39ms)	+1ms (+2.6%)	✅
article (body)	65.4 efps (15ms)	72.7 efps (14ms)	-2ms (-/-%)	✅
article (string inside object)	27.0 efps (37ms)	26.3 efps (38ms)	+1ms (+2.7%)	✅
article (string inside array)	25.0 efps (40ms)	25.0 efps (40ms)	+0ms (-/-%)	✅
recipe (name)	52.6 efps (19ms)	50.0 efps (20ms)	+1ms (+5.3%)	✅
recipe (description)	60.6 efps (17ms)	58.8 efps (17ms)	+1ms (+3.0%)	✅
recipe (instructions)	99.9+ efps (5ms)	99.9+ efps (5ms)	+0ms (-/-%)	✅
synthetic (title)	18.9 efps (53ms)	18.9 efps (53ms)	+0ms (-/-%)	✅
synthetic (string inside object)	18.9 efps (53ms)	18.9 efps (53ms)	+0ms (-/-%)	✅

efps — editor "frames per second". The number of updates assumed to be possible within a second.

Derived from input latency. efps = 1000 / input_latency

Detailed information

🏠 Reference result

The performance result of sanity@latest

Benchmark	latency	p75	p90	p99	blocking time	test duration
article (title)	38ms	41ms	43ms	159ms	177ms	10.3s
article (body)	15ms	17ms	23ms	83ms	286ms	5.5s
article (string inside object)	37ms	39ms	46ms	73ms	127ms	6.4s
article (string inside array)	40ms	41ms	44ms	154ms	132ms	6.8s
recipe (name)	19ms	20ms	25ms	42ms	0ms	7.1s
recipe (description)	17ms	18ms	21ms	39ms	0ms	4.4s
recipe (instructions)	5ms	7ms	9ms	30ms	0ms	3.2s
synthetic (title)	53ms	54ms	57ms	86ms	208ms	12.4s
synthetic (string inside object)	53ms	56ms	67ms	200ms	550ms	8.1s

🧪 Experiment result

The performance result of this branch

Benchmark	latency	p75	p90	p99	blocking time	test duration
article (title)	39ms	42ms	46ms	233ms	245ms	11.6s
article (body)	14ms	17ms	24ms	48ms	64ms	4.7s
article (string inside object)	38ms	40ms	44ms	192ms	273ms	6.7s
article (string inside array)	40ms	42ms	47ms	163ms	148ms	6.7s
recipe (name)	20ms	22ms	24ms	32ms	0ms	7.5s
recipe (description)	17ms	19ms	20ms	35ms	0ms	4.4s
recipe (instructions)	5ms	7ms	8ms	9ms	0ms	3.0s
synthetic (title)	53ms	58ms	69ms	127ms	588ms	13.6s
synthetic (string inside object)	53ms	54ms	62ms	120ms	213ms	7.5s

📚 Glossary

column definitions

• benchmark — the name of the test, e.g. "article", followed by the label of the field being measured, e.g. "(title)".
• latency — the time between when a key was pressed and when it was rendered. derived from a set of samples. the median (p50) is shown to show the most common latency.
• p75 — the 75th percentile of the input latency in the test run. 75% of the sampled inputs in this benchmark were processed faster than this value. this provides insight into the upper range of typical performance.
• p90 — the 90th percentile of the input latency in the test run. 90% of the sampled inputs were faster than this. this metric helps identify slower interactions that occurred less frequently during the benchmark.
• p99 — the 99th percentile of the input latency in the test run. only 1% of sampled inputs were slower than this. this represents the worst-case scenarios encountered during the benchmark, useful for identifying potential performance outliers.
• blocking time — the total time during which the main thread was blocked, preventing user input and UI updates. this metric helps identify performance bottlenecks that may cause the interface to feel unresponsive.
• test duration — how long the test run took to complete.