fix: string case

src/extends/string.ts

@@ -1,9 +1,103 @@
-export const toCapitalize = function toCapitalize(this: string): string {
+export const escape = function escape(this: string): string {
+  const regexp = /[&<>"']/g
+  const escapeMap: Record<string, string> = {
+    '&': '&amp;',
+    '<': '&lt;',
+    '>': '&gt;',
+    '"': '&quot;',
+    "'": '&#39;'
+  }
+
+  if (this && RegExp(regexp.source).test(this)) {
+    return this.replace(regexp, char => escapeMap[char])
+  }
+
+  return this.toString()
+}
+
+export const unescape = function unescape(this: string): string {
+  const regexp = /&(?:amp|lt|gt|quot|#(0+)?39);/g
+  const unescapeMap: Record<string, string> = {
+    '&amp;': '&',
+    '&lt;': '<',
+    '&gt;': '>',
+    '&quot;': '"',
+    '&#39;': "'"
+  }
+
+  if (this && RegExp(regexp.source).test(this)) {
+    return this.replace(regexp, entity => unescapeMap[entity] || "'")
+  }
+
+  return this.toString()
+}
+
+export const truncate = function truncate(
+  this: string,
+  length = 0,
+  truncation = '...'
+): string {
+  return this.length > length
+    ? this.slice(0, Math.max(length - truncation.length, 0)) + truncate
+    : this.toString()
+}
+
+export const capitalize = function capitalize(this: string): string {
   return this.charAt(0).toUpperCase() + this.slice(1)
 }
 
+export const upperFirst = function upperFirst(this: string): string {
+  return this.charAt(0).toUpperCase() + this.slice(1).toLowerCase()
+}
+
+export const lowerFirst = function lowerFirst(this: string): string {
+  return this.charAt(0).toLowerCase() + this.slice(1).toUpperCase()
+}
+
+export const words = function words(this: string): string[] {
+  const regexp =
+    /[A-Z]{2,}(?=[A-Z][a-z]+[0-9]*|\b)|[A-Z]?[a-z]+[0-9]*|[A-Z]|[0-9]+/g
+
+  return this.match(regexp) as string[]
+}
+
+export const camelCase = function camelCase(this: string): string {
+  return words.call(this).reduce((str, word, index) => {
+    word = word.toLowerCase()
+    return str + (index ? upperFirst.call(word) : word)
+  }, '')
+}
+
+export const snakeCase = function snakeCase(this: string): string {
+  return words.call(this).reduce((str, word, index) => {
+    return str + (index ? '_' : '') + word.toLowerCase()
+  }, '')
+}
+
+export const kebabCase = function kebabCase(this: string): string {
+  return words.call(this).reduce((str, word, index) => {
+    return str + (index ? '-' : '') + word.toLowerCase()
+  }, '')
+}
+
+export const pascalCase = function pascalCase(this: string): string {
+  return words.call(this).reduce((str, word) => {
+    return str + upperFirst.call(word)
+  }, '')
+}
+
 export const install = (): void => {
   Object.assign(String.prototype, {
-    toCapitalize
+    escape,
+    unescape,
+    truncate,
+    capitalize,
+    upperFirst,
+    lowerFirst,
+    words,
+    camelCase,
+    snakeCase,
+    kebabCase,
+    pascalCase
   })
 }