Add dynamic data-* variant (tailwindlabs#9559)

* Add data variant

* Update CHANGELOG.md

Co-authored-by: Jonathan Reinink <jonathan@reinink.ca>
Co-authored-by: Adam Wathan <4323180+adamwathan@users.noreply.github.com>

Author: adamwathan

CHANGELOG.md

@@ -30,6 +30,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Switch to positional argument + object for modifiers ([#9541](https://github.com/tailwindlabs/tailwindcss/pull/9541))
 - Add new `min` and `max` variants ([#9558](https://github.com/tailwindlabs/tailwindcss/pull/9558))
 - Add aria variants ([#9557](https://github.com/tailwindlabs/tailwindcss/pull/9557))
+- Add `data-*` variants ([#9559](https://github.com/tailwindlabs/tailwindcss/pull/9559))
 - Upgrade to `postcss-nested` v6.0 ([#9546](https://github.com/tailwindlabs/tailwindcss/pull/9546))
 
 ### Fixed

src/corePlugins.js

@@ -401,6 +401,26 @@ export let variantPlugins = {
     )
   },
 
+  dataVariants: ({ matchVariant, theme }) => {
+    matchVariant('data', (value) => `&[data-${value}]`, { values: theme('data') ?? {} })
+    matchVariant(
+      'group-data',
+      (value, { modifier }) =>
+        modifier
+          ? `:merge(.group\\/${modifier})[data-${value}] &`
+          : `:merge(.group)[data-${value}] &`,
+      { values: theme('data') ?? {} }
+    )
+    matchVariant(
+      'peer-data',
+      (value, { modifier }) =>
+        modifier
+          ? `:merge(.peer\\/${modifier})[data-${value}] ~ &`
+          : `:merge(.peer)[data-${value}] ~ &`,
+      { values: theme('data') ?? {} }
+    )
+  },
+
   orientationVariants: ({ addVariant }) => {
     addVariant('portrait', '@media (orientation: portrait)')
     addVariant('landscape', '@media (orientation: landscape)')

src/lib/setupContextUtils.js

@@ -718,6 +718,7 @@ function resolvePlugins(context, root) {
     variantPlugins['pseudoElementVariants'],
     variantPlugins['pseudoClassVariants'],
     variantPlugins['ariaVariants'],
+    variantPlugins['dataVariants'],
   ]
   let afterVariants = [
     variantPlugins['supportsVariants'],

tests/arbitrary-variants.test.js

@@ -679,6 +679,74 @@ it('should support aria variants', () => {
   })
 })
 
+fit('should support data variants', () => {
+  let config = {
+    theme: {
+      data: {
+        checked: 'ui~="checked"',
+      },
+    },
+    content: [
+      {
+        raw: html`
+          <div>
+            <div class="data-checked:underline"></div>
+            <div class="data-[position=top]:underline"></div>
+            <div class="group-data-checked:underline"></div>
+            <div class="peer-data-checked:underline"></div>
+            <div class="group-data-checked/foo:underline"></div>
+            <div class="peer-data-checked/foo:underline"></div>
+            <div class="group-data-[position=top]:underline"></div>
+            <div class="peer-data-[position=top]:underline"></div>
+            <div class="group-data-[position=top]/foo:underline"></div>
+            <div class="peer-data-[position=top]/foo:underline"></div>
+          </div>
+        `,
+      },
+    ],
+    corePlugins: { preflight: false },
+  }
+
+  let input = css`
+    @tailwind utilities;
+  `
+
+  return run(input, config).then((result) => {
+    expect(result.css).toMatchFormattedCss(css`
+      .data-checked\:underline[data-ui~='checked'] {
+        text-decoration-line: underline;
+      }
+      .data-\[position\=top\]\:underline[data-position='top'] {
+        text-decoration-line: underline;
+      }
+      .group[data-ui~='checked'] .group-data-checked\:underline {
+        text-decoration-line: underline;
+      }
+      .group\/foo[data-ui~='checked'] .group-data-checked\/foo\:underline {
+        text-decoration-line: underline;
+      }
+      .group[data-position='top'] .group-data-\[position\=top\]\:underline {
+        text-decoration-line: underline;
+      }
+      .group\/foo[data-position='top'] .group-data-\[position\=top\]\/foo\:underline {
+        text-decoration-line: underline;
+      }
+      .peer[data-ui~='checked'] ~ .peer-data-checked\:underline {
+        text-decoration-line: underline;
+      }
+      .peer\/foo[data-ui~='checked'] ~ .peer-data-checked\/foo\:underline {
+        text-decoration-line: underline;
+      }
+      .peer[data-position='top'] ~ .peer-data-\[position\=top\]\:underline {
+        text-decoration-line: underline;
+      }
+      .peer\/foo[data-position='top'] ~ .peer-data-\[position\=top\]\/foo\:underline {
+        text-decoration-line: underline;
+      }
+    `)
+  })
+})
+
 it('should support supports', () => {
   let config = {
     theme: {