Skip to content

[babel-plugin] Fix corrupted class names from null coercion in dynamic styles #1731

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
henryqdineen wants to merge 2 commits into
base: main
Choose a base branch
from
+34 −34
Open

[babel-plugin] Fix corrupted class names from null coercion in dynamic styles #1731

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b2b4686
[babel-plugin] Fix corrupted class names from null coercion in dynami…
henryqdineen Jun 22, 2026
a4889e8
[babel-plugin] Update remaining snapshots for null coercion fix
henryqdineen Jun 22, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion packages/@stylexjs/babel-plugin/__tests__/evaluation-import-test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -402,7 +402,7 @@ describe('Evaluation of imported values works based on configuration', () => {
});
const styles = {
color: color => [{
"--__hashed_var__1jqb1tb": color != null ? "__hashed_var__1w8wjxo" : color,
"--__hashed_var__1jqb1tb": color != null ? "__hashed_var__1w8wjxo" : "",

@nmn nmn Jul 13, 2026

Copy link
Copy Markdown
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This is a small regression because the reason the fallback value was color is to account for the way undefined vs null is handled by stylex. null means intentionally unsetting a value. undefined is to ignored and the previously set value wins. Here all nullish values are represented as "" which behaves like null.

@nmn nmn Jul 13, 2026

Copy link
Copy Markdown
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Perhaps what we need here is:

color !== undefined && {"--__hashed_var__1jqb1tb": color != null ? "__hashed_var__1w8wjxo" : "", $$css: true}

This way, we can skip the object for undefined entirely.

$$css: true
}, {
"--x---__hashed_var__1jqb1tb": color != null ? color : undefined
Expand Down
6 changes: 3 additions & 3 deletions packages/@stylexjs/babel-plugin/__tests__/transform-process-test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -240,7 +240,7 @@ describe('@stylexjs/babel-plugin', () => {
$$css: "components/main.js:71"
},
dynamic: color => [{
"color-kMwMTN": color != null ? "color-x14rh7hd" : color,
"color-kMwMTN": color != null ? "color-x14rh7hd" : "",
$$css: "components/main.js:74"
}, {
"--x-color": color != null ? color : undefined
Expand Down Expand Up @@ -333,7 +333,7 @@ describe('@stylexjs/babel-plugin', () => {
$$css: "main.js:71"
},
dynamic: color => [{
"color-kMwMTN": color != null ? "color-x14rh7hd" : color,
"color-kMwMTN": color != null ? "color-x14rh7hd" : "",
$$css: "main.js:74"
}, {
"--x-color": color != null ? color : undefined
Expand Down Expand Up @@ -781,7 +781,7 @@ describe('@stylexjs/babel-plugin', () => {
$$css: "main.js:71"
},
dynamic: color => [{
"color-kMwMTN": color != null ? "color-x14rh7hd" : color,
"color-kMwMTN": color != null ? "color-x14rh7hd" : "",
$$css: "main.js:74"
}, {
"--x-color": color != null ? color : undefined
Expand Down
46 changes: 23 additions & 23 deletions packages/@stylexjs/babel-plugin/__tests__/transform-stylex-create-test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3645,7 +3645,7 @@ describe('@stylexjs/babel-plugin', () => {
};
export const styles = {
root: color => [_temp, {
kMwMTN: color != null ? "x14rh7hd" : color,
kMwMTN: color != null ? "x14rh7hd" : "",
$$css: true
}, {
"--x-color": color != null ? color : undefined
Expand Down Expand Up @@ -3700,7 +3700,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
one: color => [{
kMwMTN: color != null ? "x14rh7hd" : color,
kMwMTN: color != null ? "x14rh7hd" : "",
$$css: true
}, {
"--x-color": color != null ? color : undefined
Expand Down Expand Up @@ -3758,8 +3758,8 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: (bgColor, otherColor) => [{
"--background-color": bgColor != null ? "xwn82o0" : bgColor,
"--otherColor": otherColor != null ? "xp3hsad" : otherColor,
"--background-color": bgColor != null ? "xwn82o0" : "",
"--otherColor": otherColor != null ? "xp3hsad" : "",
$$css: true
}, {
"--x---background-color": bgColor != null ? bgColor : undefined,
Expand Down Expand Up @@ -3822,7 +3822,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: width => [{
kzqmXN: width != null ? "x5lhr3w" : width,
kzqmXN: width != null ? "x5lhr3w" : "",
$$css: true
}, {
"--x-width": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(width)
Expand Down Expand Up @@ -3874,7 +3874,7 @@ describe('@stylexjs/babel-plugin', () => {
};
export const styles = {
root: width => [_temp, {
kzqmXN: width != null ? "x5lhr3w" : width,
kzqmXN: width != null ? "x5lhr3w" : "",
$$css: true
}, {
"--x-width": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(width),
Expand Down Expand Up @@ -3953,7 +3953,7 @@ describe('@stylexjs/babel-plugin', () => {
import { vars } from 'vars.stylex.js';
export const styles = {
root: width => [{
"--x1anmu0j": width != null ? "x5fq457" : width,
"--x1anmu0j": width != null ? "x5fq457" : "",
$$css: true
}, {
"--x---x1anmu0j": width != null ? width : undefined
Expand Down Expand Up @@ -4407,7 +4407,7 @@ describe('@stylexjs/babel-plugin', () => {
};
export const styles = {
root: (color, isDark) => [_temp, {
kMwMTN: (isDark ? color : 'black') != null ? "x14rh7hd" : isDark ? color : 'black',
kMwMTN: (isDark ? color : 'black') != null ? "x14rh7hd" : "",
$$css: true
}, {
"--x-backgroundColor": (isDark ? 'black' : 'white') != null ? isDark ? 'black' : 'white' : undefined,
Expand Down Expand Up @@ -4577,8 +4577,8 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: color => [{
kWkggS: color != null ? "x1j2k28p" : color,
kMwMTN: color != null ? "x1qvlgnj" : color,
kWkggS: color != null ? "x1j2k28p" : "",
kMwMTN: color != null ? "x1qvlgnj" : "",
$$css: true
}, {
"--x-1e2mv7m": color != null ? color : undefined,
Expand Down Expand Up @@ -4644,7 +4644,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: (hover, active, focus) => [{
kMwMTN: (hover != null ? "x1qvlgnj " : hover) + (active != null ? "xx746rz " : active) + (focus != null ? "x152n5rj " : focus) + "x126ychx",
kMwMTN: (hover != null ? "x1qvlgnj " : "") + (active != null ? "xx746rz " : "") + (focus != null ? "x152n5rj " : "") + "x126ychx",
$$css: true
}, {
"--x-1113oo7": hover != null ? hover : undefined,
Expand Down Expand Up @@ -4737,8 +4737,8 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
foo: (a, b) => [{
kxBb7d: a != null ? "xaigonn" : a,
kB1Fuz: b != null ? "x1p1099i" : b,
kxBb7d: a != null ? "xaigonn" : "",
kB1Fuz: b != null ? "x1p1099i" : "",
$$css: true
}, {
"--x-1g451k2": a != null ? a : undefined,
Expand Down Expand Up @@ -4801,7 +4801,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
foo: color => [{
k8Qsv1: color != null ? "x1mzl164" : color,
k8Qsv1: color != null ? "x1mzl164" : "",
$$css: true
}, {
"--x-163tekb": color != null ? color : undefined
Expand Down Expand Up @@ -4847,7 +4847,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
foo: width => [{
k8pbKx: width != null ? "x18fgbt0" : width,
k8pbKx: width != null ? "x18fgbt0" : "",
$$css: true
}, {
"--x-msahdu": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(width)
Expand Down Expand Up @@ -4951,7 +4951,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
repro: color => [{
kB1Fuz: color != null ? "x1p1099i" : color,
kB1Fuz: color != null ? "x1p1099i" : "",
$$css: true
}, {
"--x-19erzii": color != null ? color : undefined
Expand Down Expand Up @@ -5001,7 +5001,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: (a, b, c) => [{
kzqmXN: "x11ymkkh " + "x38mdg9 " + (c != null ? "x1bai16n" : c),
kzqmXN: "x11ymkkh " + "x38mdg9 " + (c != null ? "x1bai16n" : ""),
$$css: true
}, {
"--x-1xmrurk": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)('color-mix(' + color + ', blue)'),
Expand Down Expand Up @@ -5083,7 +5083,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: (a, b, c) => [{
kMwMTN: (a != null ? "x3d248p " : a) + (b != null ? "x1iuwwch " : b) + (c != null ? "x5268pl" : c),
kMwMTN: (a != null ? "x3d248p " : "") + (b != null ? "x1iuwwch " : "") + (c != null ? "x5268pl" : ""),
$$css: true
}, {
"--x-4xs81a": a != null ? a : undefined,
Expand Down Expand Up @@ -5167,7 +5167,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: (a, b, c) => [{
kGuDYH: (a != null ? "xww4jgc " : a) + (b != null ? "xfqys7t " : b) + (c != null ? "x13w7uki" : c),
kGuDYH: (a != null ? "xww4jgc " : "") + (b != null ? "xfqys7t " : "") + (c != null ? "x13w7uki" : ""),
$$css: true
}, {
"--x-19zvkyr": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(a),
Expand Down Expand Up @@ -5250,7 +5250,7 @@ describe('@stylexjs/babel-plugin', () => {
"import * as stylex from '@stylexjs/stylex';
export const styles = {
root: (a, b, c) => [{
kGuDYH: ((a ? '16px' : undefined) != null ? "xww4jgc " : a ? '16px' : undefined) + ((b ? '18px' : undefined) != null ? "xqdov8i " : b ? '18px' : undefined) + ((c ? '20px' : undefined) != null ? "x1j86d60" : c ? '20px' : undefined),
kGuDYH: ((a ? '16px' : undefined) != null ? "xww4jgc " : "") + ((b ? '18px' : undefined) != null ? "xqdov8i " : "") + ((c ? '20px' : undefined) != null ? "x1j86d60" : ""),
$$css: true
}, {
"--x-19zvkyr": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(a ? '16px' : undefined),
Expand Down Expand Up @@ -6042,9 +6042,9 @@ describe('@stylexjs/babel-plugin', () => {
});
export const styles = {
default: margin => [_temp, {
k71WvV: (margin != null ? "x17e2bsb " : margin) + "xtcj1g9",
k1K539: (margin != null ? "xg6eqc8 " : margin) + "xgrn1a3",
keTefX: (margin != null ? "x19ja4a5 " : margin) + "x2tye95",
k71WvV: (margin != null ? "x17e2bsb " : "") + "xtcj1g9",
k1K539: (margin != null ? "xg6eqc8 " : "") + "xgrn1a3",
keTefX: (margin != null ? "x19ja4a5 " : "") + "x2tye95",
$$css: true
}, {
"--x-14mfytm": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(margin),
Expand Down
4 changes: 2 additions & 2 deletions packages/@stylexjs/babel-plugin/__tests__/transform-stylex-defineConsts-test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -543,7 +543,7 @@ describe('@stylexjs/babel-plugin', () => {
};
export const styles = {
node: padding => [_temp, {
kmVPX3: padding != null ? "x1fozly0" : padding,
kmVPX3: padding != null ? "x1fozly0" : "",
$$css: true
}, {
"--x-padding": (val => typeof val === "number" ? val + "px" : val != null ? val : undefined)(padding)
Expand Down Expand Up @@ -603,7 +603,7 @@ describe('@stylexjs/babel-plugin', () => {
import { breakpoints } from './constants.stylex';
export const styles = {
node: color => [{
kMwMTN: "xbs0o1n " + (color != null ? "x3d248p" : color),
kMwMTN: "xbs0o1n " + (color != null ? "x3d248p" : ""),
$$css: true
}, {
"--x-4xs81a": color != null ? color : undefined
Expand Down
8 changes: 4 additions & 4 deletions packages/@stylexjs/babel-plugin/__tests__/transform-stylex-props-test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -544,7 +544,7 @@ describe('@stylexjs/babel-plugin', () => {
$$css: "npm-package:js/node_modules/npm-package/dist/components/Foo.react.js:4"
},
opacity: opacity => [{
"opacity-kSiTet": opacity != null ? "opacity-xb4nw82" : opacity,
"opacity-kSiTet": opacity != null ? "opacity-xb4nw82" : "",
$$css: "npm-package:js/node_modules/npm-package/dist/components/Foo.react.js:7"
}, {
"--x-opacity": opacity != null ? opacity : undefined
Expand Down Expand Up @@ -806,7 +806,7 @@ describe('@stylexjs/babel-plugin', () => {
});
const styles = {
color: c => [{
kMwMTN: c != null ? "x14rh7hd" : c,
kMwMTN: c != null ? "x14rh7hd" : "",
$$css: true
}, {
"--x-color": c != null ? c : undefined
Expand Down Expand Up @@ -902,7 +902,7 @@ describe('@stylexjs/babel-plugin', () => {
});
const styles = {
opacity: o => [{
kSiTet: o != null ? "xb4nw82" : o,
kSiTet: o != null ? "xb4nw82" : "",
$$css: true
}, {
"--x-opacity": o != null ? o : undefined
Expand Down Expand Up @@ -944,7 +944,7 @@ describe('@stylexjs/babel-plugin', () => {
});
const styles = {
opacity: o => [{
kSiTet: o != null ? "xb4nw82" : o,
kSiTet: o != null ? "xb4nw82" : "",
$$css: true
}, {
"--x-opacity": o != null ? o : undefined
Expand Down
2 changes: 1 addition & 1 deletion packages/@stylexjs/babel-plugin/src/visitors/stylex-create.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -421,7 +421,7 @@ export default function transformStyleXCreate(
t.conditionalExpression(
t.binaryExpression('!=', expr, t.nullLiteral()),
t.stringLiteral(clsWithSpace),
expr,
t.stringLiteral(''),
),
);
} else {
Expand Down
Loading