Move CSS validation helpers to separate file

wip

src/lib/generateRules.js

@@ -12,6 +12,7 @@ import { normalize } from '../util/dataTypes'
 import { isValidVariantFormatString, parseVariant } from './setupContextUtils'
 import isValidArbitraryValue from '../util/isValidArbitraryValue'
 import { splitAtTopLevelOnly } from '../util/splitAtTopLevelOnly.js'
+import { isParsableNode, isParsableCssValue, isValidPropName } from '../util/css-validation.js'
 
 let classNameParser = selectorParser((selectors) => {
   return selectors.first.filter(({ type }) => type === 'class').pop().value
@@ -303,61 +304,6 @@ function parseRules(rule, cache, options = {}) {
   return [cache.get(rule), options]
 }
 
-const IS_VALID_PROPERTY_NAME = /^[a-z_-]/
-
-function isValidPropName(name) {
-  return IS_VALID_PROPERTY_NAME.test(name)
-}
-
-/**
- * @param {string} declaration
- * @returns {boolean}
- */
-function looksLikeUri(declaration) {
-  // Quick bailout for obvious non-urls
-  // This doesn't support schemes that don't use a leading // but that's unlikely to be a problem
-  if (!declaration.includes('://')) {
-    return false
-  }
-
-  try {
-    const url = new URL(declaration)
-    return url.scheme !== '' && url.host !== ''
-  } catch (err) {
-    // Definitely not a valid url
-    return false
-  }
-}
-
-function isParsableNode(node) {
-  let isParsable = true
-
-  node.walkDecls((decl) => {
-    if (!isParsableCssValue(decl.name, decl.value)) {
-      isParsable = false
-      return false
-    }
-  })
-
-  return isParsable
-}
-
-function isParsableCssValue(property, value) {
-  // We don't want to to treat [https://example.com] as a custom property
-  // Even though, according to the CSS grammar, it's a totally valid CSS declaration
-  // So we short-circuit here by checking if the custom property looks like a url
-  if (looksLikeUri(`${property}:${value}`)) {
-    return false
-  }
-
-  try {
-    postcss.parse(`a{${property}:${value}}`).toResult()
-    return true
-  } catch (err) {
-    return false
-  }
-}
-
 function extractArbitraryProperty(classCandidate, context) {
   let [, property, value] = classCandidate.match(/^\[([a-zA-Z0-9-_]+):(\S+)\]$/) ?? []
 

src/util/css-validation.js

@@ -0,0 +1,56 @@
+import postcss from 'postcss'
+
+const IS_VALID_PROPERTY_NAME = /^[a-z_-]/
+
+export function isValidPropName(name) {
+  return IS_VALID_PROPERTY_NAME.test(name)
+}
+
+/**
+ * @param {string} declaration
+ * @returns {boolean}
+ */
+export function looksLikeUri(declaration) {
+  // Quick bailout for obvious non-urls
+  // This doesn't support schemes that don't use a leading // but that's unlikely to be a problem
+  if (!declaration.includes('://')) {
+    return false
+  }
+
+  try {
+    const url = new URL(declaration)
+    return url.scheme !== '' && url.host !== ''
+  } catch (err) {
+    // Definitely not a valid url
+    return false
+  }
+}
+
+export function isParsableNode(node) {
+  let isParsable = true
+
+  node.walkDecls((decl) => {
+    if (!isParsableCssValue(decl.name, decl.value)) {
+      isParsable = false
+      return false
+    }
+  })
+
+  return isParsable
+}
+
+export function isParsableCssValue(property, value) {
+  // We don't want to to treat [https://example.com] as a custom property
+  // Even though, according to the CSS grammar, it's a totally valid CSS declaration
+  // So we short-circuit here by checking if the custom property looks like a url
+  if (looksLikeUri(`${property}:${value}`)) {
+    return false
+  }
+
+  try {
+    postcss.parse(`a{${property}:${value}}`).toResult()
+    return true
+  } catch (err) {
+    return false
+  }
+}