Refactor

Author: thecrypticace

packages/tailwindcss-language-service/src/util/css-vars.ts

@@ -1,4 +1,16 @@
 export function replaceCssVarsWithFallbacks(str: string): string {
+  return replaceCssVars(str, (name, fallback) => {
+    // If we have a fallback then we should use that value directly
+    if (fallback) return fallback
+
+    // Don't replace the variable otherwise
+    return null
+  })
+}
+
+type CssVarReplacer = (name: string, fallback: string | null) => string | null
+
+function replaceCssVars(str: string, replace: CssVarReplacer): string {
   for (let i = 0; i < str.length; ++i) {
     if (!str.startsWith('var(', i)) continue
 
@@ -13,17 +25,25 @@ export function replaceCssVarsWithFallbacks(str: string): string {
       } else if (str[j] === ',' && depth === 0 && fallbackStart === null) {
         fallbackStart = j + 1
       } else if (str[j] === ')' && depth === 0) {
-        if (fallbackStart === null) {
-          i = j + 1
+        let varName = str.slice(i + 4, j)
+        let fallback = fallbackStart === null ? null : str.slice(fallbackStart, j)
+        let replacement = replace(varName, fallback)
+
+        if (replacement !== null) {
+          str = str.slice(0, i) + replacement + str.slice(j + 1)
+
+          // We don't want to skip past anything here because `replacement`
+          // might contain more var(…) calls in which case `i` will already
+          // be pointing at the right spot to start looking for them
           break
         }
 
-        let fallbackEnd = j
-        str = str.slice(0, i) + str.slice(fallbackStart, fallbackEnd) + str.slice(j + 1)
+        // Skip past the closing parenthesis and onto the next `var(`
+        i = j + 1
         break
       }
     }
   }
 
   return str
-}
+}

packages/tailwindcss-language-service/src/util/v4/design-system.ts

@@ -3,7 +3,7 @@ import type { Rule } from './ast'
 import type { NamedVariant } from './candidate'
 
 export interface Theme {
-  // Prefix didn't exist on
+  // Prefix didn't exist for earlier Tailwind versions
   prefix?: string
   entries(): [string, any][]
 }