minor: better type safety and best practice to escape function

integrations/utils.ts

@@ -6,6 +6,7 @@ import { platform, tmpdir } from 'node:os'
 import path from 'node:path'
 import { stripVTControlCharacters } from 'node:util'
 import { test as defaultTest, type ExpectStatic } from 'vitest'
+import { escape } from '../packages/tailwindcss/src/utils/escape'
 
 const REPO_ROOT = path.join(__dirname, '..')
 const PUBLIC_PACKAGES = (await fs.readdir(path.join(REPO_ROOT, 'dist'))).map((name) =>
@@ -521,80 +522,6 @@ export function candidate(strings: TemplateStringsArray, ...values: any[]) {
   return `.${escape(output.join('').trim())}`
 }
 
-// https://drafts.csswg.org/cssom/#serialize-an-identifier
-export function escape(value: string) {
-  if (arguments.length == 0) {
-    throw new TypeError('`CSS.escape` requires an argument.')
-  }
-  var string = String(value)
-  var length = string.length
-  var index = -1
-  var codeUnit
-  var result = ''
-  var firstCodeUnit = string.charCodeAt(0)
-
-  if (
-    // If the character is the first character and is a `-` (U+002D), and
-    // there is no second character, […]
-    length == 1 &&
-    firstCodeUnit == 0x002d
-  ) {
-    return '\\' + string
-  }
-
-  while (++index < length) {
-    codeUnit = string.charCodeAt(index)
-    // Note: there’s no need to special-case astral symbols, surrogate
-    // pairs, or lone surrogates.
-
-    // If the character is NULL (U+0000), then the REPLACEMENT CHARACTER
-    // (U+FFFD).
-    if (codeUnit == 0x0000) {
-      result += '\uFFFD'
-      continue
-    }
-
-    if (
-      // If the character is in the range [\1-\1F] (U+0001 to U+001F) or is
-      // U+007F, […]
-      (codeUnit >= 0x0001 && codeUnit <= 0x001f) ||
-      codeUnit == 0x007f ||
-      // If the character is the first character and is in the range [0-9]
-      // (U+0030 to U+0039), […]
-      (index == 0 && codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
-      // If the character is the second character and is in the range [0-9]
-      // (U+0030 to U+0039) and the first character is a `-` (U+002D), […]
-      (index == 1 && codeUnit >= 0x0030 && codeUnit <= 0x0039 && firstCodeUnit == 0x002d)
-    ) {
-      // https://drafts.csswg.org/cssom/#escape-a-character-as-code-point
-      result += '\\' + codeUnit.toString(16) + ' '
-      continue
-    }
-
-    // If the character is not handled by one of the above rules and is
-    // greater than or equal to U+0080, is `-` (U+002D) or `_` (U+005F), or
-    // is in one of the ranges [0-9] (U+0030 to U+0039), [A-Z] (U+0041 to
-    // U+005A), or [a-z] (U+0061 to U+007A), […]
-    if (
-      codeUnit >= 0x0080 ||
-      codeUnit == 0x002d ||
-      codeUnit == 0x005f ||
-      (codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
-      (codeUnit >= 0x0041 && codeUnit <= 0x005a) ||
-      (codeUnit >= 0x0061 && codeUnit <= 0x007a)
-    ) {
-      // the character itself
-      result += string.charAt(index)
-      continue
-    }
-
-    // Otherwise, the escaped character.
-    // https://drafts.csswg.org/cssom/#escape-a-character
-    result += '\\' + string.charAt(index)
-  }
-  return result
-}
-
 export async function retryAssertion<T>(
   fn: () => Promise<T>,
   { timeout = ASSERTION_TIMEOUT, delay = 5 }: { timeout?: number; delay?: number } = {},

packages/tailwindcss/src/utils/escape.ts

@@ -1,20 +1,20 @@
 // https://drafts.csswg.org/cssom/#serialize-an-identifier
 export function escape(value: string) {
-  if (arguments.length == 0) {
+  if (arguments.length === 0) {
     throw new TypeError('`CSS.escape` requires an argument.')
   }
-  var string = String(value)
-  var length = string.length
-  var index = -1
-  var codeUnit
-  var result = ''
-  var firstCodeUnit = string.charCodeAt(0)
+  let string = String(value)
+  let length = string.length
+  let index = -1
+  let codeUnit: number
+  let result = ''
+  let firstCodeUnit = string.charCodeAt(0)
 
   if (
     // If the character is the first character and is a `-` (U+002D), and
     // there is no second character, […]
-    length == 1 &&
-    firstCodeUnit == 0x002d
+    length === 1 &&
+    firstCodeUnit === 0x002d
   ) {
     return '\\' + string
   }
@@ -26,7 +26,7 @@ export function escape(value: string) {
 
     // If the character is NULL (U+0000), then the REPLACEMENT CHARACTER
     // (U+FFFD).
-    if (codeUnit == 0x0000) {
+    if (codeUnit === 0x0000) {
       result += '\uFFFD'
       continue
     }
@@ -35,13 +35,13 @@ export function escape(value: string) {
       // If the character is in the range [\1-\1F] (U+0001 to U+001F) or is
       // U+007F, […]
       (codeUnit >= 0x0001 && codeUnit <= 0x001f) ||
-      codeUnit == 0x007f ||
+      codeUnit === 0x007f ||
       // If the character is the first character and is in the range [0-9]
       // (U+0030 to U+0039), […]
-      (index == 0 && codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
+      (index === 0 && codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
       // If the character is the second character and is in the range [0-9]
       // (U+0030 to U+0039) and the first character is a `-` (U+002D), […]
-      (index == 1 && codeUnit >= 0x0030 && codeUnit <= 0x0039 && firstCodeUnit == 0x002d)
+      (index === 1 && codeUnit >= 0x0030 && codeUnit <= 0x0039 && firstCodeUnit === 0x002d)
     ) {
       // https://drafts.csswg.org/cssom/#escape-a-character-as-code-point
       result += '\\' + codeUnit.toString(16) + ' '
@@ -54,8 +54,8 @@ export function escape(value: string) {
     // U+005A), or [a-z] (U+0061 to U+007A), […]
     if (
       codeUnit >= 0x0080 ||
-      codeUnit == 0x002d ||
-      codeUnit == 0x005f ||
+      codeUnit === 0x002d ||
+      codeUnit === 0x005f ||
       (codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
       (codeUnit >= 0x0041 && codeUnit <= 0x005a) ||
       (codeUnit >= 0x0061 && codeUnit <= 0x007a)