Prevent invalid arbitrary variant selectors from failing the build

CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Don’t reorder webkit scrollbar pseudo elements ([#9991](https://github.com/tailwindlabs/tailwindcss/pull/9991))
 - Deterministic sorting of arbitrary variants ([#10016](https://github.com/tailwindlabs/tailwindcss/pull/10016))
 - Add `data` key to theme types ([#10023](https://github.com/tailwindlabs/tailwindcss/pull/10023))
+- Prevent invalid arbitrary variant selectors from failing the build ([#10059](https://github.com/tailwindlabs/tailwindcss/pull/10059))
 
 ### Changed
 

src/lib/generateRules.js

@@ -733,6 +733,8 @@ function* resolveMatches(candidate, context, original = candidate) {
     }
 
     for (let match of matches) {
+      let isValid = true
+
       match[1].raws.tailwind = { ...match[1].raws.tailwind, candidate }
 
       // Apply final format selector
@@ -742,7 +744,7 @@ function* resolveMatches(candidate, context, original = candidate) {
         container.walkRules((rule) => {
           if (inKeyframes(rule)) return
 
-          rule.selector = finalizeSelector(finalFormat, {
+          let selectorOptions = {
             selector: rule.selector,
             candidate: original,
             base: candidate
@@ -751,11 +753,31 @@ function* resolveMatches(candidate, context, original = candidate) {
             isArbitraryVariant: match[0].isArbitraryVariant,
 
             context,
-          })
+          }
+
+          try {
+            rule.selector = finalizeSelector(finalFormat, selectorOptions)
+          } catch {
+            // The selector we produced is invalid
+            // This could be because:
+            // - A bug exists
+            // - A plugin introduced an invalid variant selector (ex: `addVariant('foo', '&;foo')`)
+            // - The user used an invalid arbitrary variant (ex: `[&;foo]:underline`)
+            // Either way the build will fail because of this
+            // We would rather that the build pass "silently" given that this could
+            // happen because of picking up invalid things when scanning content
+            // So we'll throw out the candidate instead
+            isValid = false
+            return false
+          }
         })
         match[1] = container.nodes[0]
       }
 
+      if (!isValid) {
+        continue
+      }
+
       yield match
     }
   }

tests/arbitrary-variants.test.js

@@ -1099,3 +1099,47 @@ it('Arbitrary variants are ordered alphabetically', () => {
     `)
   })
 })
+
+it('Arbitrary variants support multiple attribute selectors', () => {
+  let config = {
+    content: [
+      {
+        raw: html` <div class="[[data-foo='bar'][data-baz]_&]:underline"></div> `,
+      },
+    ],
+    corePlugins: { preflight: false },
+  }
+
+  let input = css`
+    @tailwind utilities;
+  `
+
+  return run(input, config).then((result) => {
+    expect(result.css).toMatchFormattedCss(css`
+      [data-foo='bar'][data-baz] .\[\[data-foo\=\'bar\'\]\[data-baz\]_\&\]\:underline {
+        text-decoration-line: underline;
+      }
+    `)
+  })
+})
+
+it('Invalid arbitrary variants selectors should produce nothing instead of failing', () => {
+  let config = {
+    content: [
+      {
+        raw: html`
+          <div class="[&;foo]:underline"></div>
+        `,
+      },
+    ],
+    corePlugins: { preflight: false },
+  }
+
+  let input = css`
+    @tailwind utilities;
+  `
+
+  return run(input, config).then((result) => {
+    expect(result.css).toMatchFormattedCss(css``)
+  })
+})