Skip to content

Add support for @starting-style rules #1566

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
wants to merge 2 commits into
base: master
Choose a base branch
from
Open

Add support for @starting-style rules #1566

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
1eaa63e
Add transform function for @starting-style
lfantone May 16, 2025
dca4c7c
Apply suggestions from code review
askoufis Sep 22, 2025
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
17 changes: 17 additions & 0 deletions .changeset/tender-beans-cheat.md
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,17 @@
---
'@vanilla-extract/css': minor
---

`style`: Add support for `@starting-style` rules

**EXAMPLE USAGE**:

```ts
import { style } from '@vanilla-extact/css';
export const styleWithStartingStyle = style({
backgroundColor: 'black',
'@starting-style': {
backgroundColor: 'white',
},
});
``
7 changes: 7 additions & 0 deletions fixtures/features/src/features.css.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -60,3 +60,10 @@ export const styleVariantsCompositionInSelector = styleVariants({
globalStyle(`body ${styleVariantsCompositionInSelector.variant}`, {
fontSize: '24px',
});

export const styleWithStartingStyle = style({
backgroundColor: 'black',
'@starting-style': {
backgroundColor: 'white',
},
});
1 change: 1 addition & 0 deletions fixtures/features/src/html.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@ export default `
<div id="${testNodes.compositionOnly}" class="${styles.compositionOnly}">Composition only</div>
<div id="${testNodes.styleCompositionInSelector}" class="${styles.styleCompositionInSelector}">Style composition in selector</div>
<div id="${testNodes.styleVariantsCompositionInSelector}" class="${styles.styleVariantsCompositionInSelector.variant}">Style variants composition in selector</div>
<div id="${testNodes.styleWithStartingStyle}" class="${styles.styleWithStartingStyle}">Style with @starting-style rule</div>
`;

// @ts-expect-error Vite env not defined
Expand Down
3 changes: 2 additions & 1 deletion fixtures/features/test-nodes.json
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,5 +5,6 @@
"styleVariantsWithMappedComposition": "styleVariantsWithMappedComposition",
"compositionOnly": "compositionOnly",
"styleCompositionInSelector": "styleCompositionInSelector",
"styleVariantsCompositionInSelector": "styleVariantsCompositionInSelector"
"styleVariantsCompositionInSelector": "styleVariantsCompositionInSelector",
"styleWithStartingStyle": "styleWithStartingStyle"
}
334 changes: 334 additions & 0 deletions packages/css/src/transformCss.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2500,6 +2500,340 @@ describe('transformCss', () => {
}
`);
});

it('should handle @starting-style declaration', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
opacity: 1,
top: '100%',
'@starting-style': {
opacity: 0,
top: '50%',
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
.testClass {
opacity: 1;
top: 100%;
@starting-style {
opacity: 0;
top: 50%;
}
}
`);
});

it('should handle @starting-style inside media queries', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
display: 'flex',
'@media': {
'screen and (min-width: 700px)': {
top: '0',
'@starting-style': {
top: '100%',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
.testClass {
display: flex;
}
@media screen and (min-width: 700px) {
.testClass {
top: 0;
@starting-style {
top: 100%;
}
}
}
`);
});

it('should handle @starting-style inside container queries', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
'@container': {
'sidebar (min-width: 700px)': {
top: '0',
'@starting-style': {
top: '100%',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
@container sidebar (min-width: 700px) {
.testClass {
top: 0;
@starting-style {
top: 100%;
}
}
}
`);
});

it('should handle @starting-style inside a layer', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
'@layer': {
'mock-layer': {
top: '0',
'@starting-style': {
top: '100%',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
@layer mock-layer;
@layer mock-layer {
.testClass {
top: 0;
@starting-style {
top: 100%;
}
}
}
`);
});

it('should handle @starting-style inside selectors', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
selectors: {
'&:hover': {
top: '0',
'@starting-style': {
top: '100%',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
.testClass:hover {
top: 0;
@starting-style {
top: 100%;
}
}
`);
});

it('should handle @starting-style inside @supports', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
'@supports': {
'(display: grid)': {
top: '0',
'@starting-style': {
top: '100%',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
@supports (display: grid) {
.testClass {
top: 0;
@starting-style {
top: 100%;
}
}
}
`);
});

it('should process both simple pseudos and selectors inside @starting-style', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
'@starting-style': {
color: 'green',
':hover': {
color: 'red',
},
':focus': {
backgroundColor: 'blue',
},
selectors: {
'&.active': {
color: 'purple',
},
'& + &': {
marginLeft: '10px',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
.testClass {
@starting-style {
color: green;
:hover {
color: red;
}
:focus {
background-color: blue;
}
selectors {
&.active {
color: purple;
}
& + & {
margin-left: 10px;
}
}
}
}
`);
});

it('should not process simple pseudos and selectors inside @starting-style for non-local root types', () => {
expect(
transformCss({
composedClassLists: [],
localClassNames: [],
cssObjs: [
{
type: 'global',
selector: '.globalClass',
rule: {
'@starting-style': {
color: 'green',
':hover': {
color: 'red',
},
':focus': {
backgroundColor: 'blue',
},
selectors: {
'&.active': {
color: 'purple',
},
},
},
},
},
],
}).join('\n'),
).toMatchInlineSnapshot(`
.globalClass {
@starting-style {
color: green;
:hover {
color: red;
}
:focus {
background-color: blue;
}
selectors {
&.active {
color: purple;
}
}
}
}
`);
});

it('should throw an error when a at-rule is use inside @starting-style scope', () => {
expect(() =>
transformCss({
composedClassLists: [],
localClassNames: ['testClass'],
cssObjs: [
{
type: 'local',
selector: 'testClass',
rule: {
'@starting-style': {
// @ts-expect-error - Using a media query inside @starting-style for testing purposes
'@media': {
'screen and (min-width: 700px)': {
display: 'grid',
},
},
},
},
},
],
}),
).toThrowErrorMatchingInlineSnapshot(
'Nested at-rules (e.g. "@media") are not allowed inside @starting-style.',
);
});
});

endFileScope();
Loading