feat: implement quoteStyle option

Author: SukkaW

lib/index.js

@@ -59,12 +59,17 @@ function render(tree, options) {
     replaceQuote = true;
   }
 
+  let {quoteStyle} = options;
+  if (quoteStyle === undefined) {
+    quoteStyle = 2;
+  }
+
   return html(tree);
 
   /** @private */
   function isSingleTag(tag) {
     if (singleRegExp.length > 0) {
-      return singleRegExp.some(reg => reg.test(tag))
+      return singleRegExp.some(reg => reg.test(tag));
     }
 
     if (!singleTags.includes(tag)) {
@@ -87,7 +92,7 @@ function render(tree, options) {
             attrValue = object[key].replace(/"/g, '"');
           }
 
-          attr += ' ' + key + '="' + attrValue + '"';
+          attr += makeAttr(key, attrValue, quoteStyle);
         } else if (object[key] === '') {
           attr += ' ' + key;
         } else {
@@ -96,7 +101,7 @@ function render(tree, options) {
       } else if (object[key] === true) {
         attr += ' ' + key;
       } else if (typeof object[key] === 'number') {
-        attr += ' ' + key + '="' + object[key] + '"';
+        attr += makeAttr(key, object[key], quoteStyle);
       }
     }
 
@@ -112,6 +117,26 @@ function render(tree, options) {
     }
   }
 
+  /** @private */
+  function makeAttr(key, attrValue, quoteStyle = 1) {
+    if (quoteStyle === 1) {
+      // Single Quote
+      return ` ${key}='${attrValue}'`;
+    }
+
+    if (quoteStyle === 2) {
+      // Double Quote
+      return ` ${key}="${attrValue}"`;
+    }
+
+    // Smart Quote
+    if (attrValue.includes('"')) {
+      return ` ${key}='${attrValue}'`;
+    }
+
+    return ` ${key}="${attrValue}"`;
+  }
+
   /**
    * HTML Stringifier
    *
@@ -129,10 +154,10 @@ function render(tree, options) {
     traverse(tree, node => {
       // Undefined, null, '', [], NaN
       if (node === undefined ||
-          node === null ||
-          node === false ||
-          node.length === 0 ||
-          Number.isNaN(node)) {
+        node === null ||
+        node === false ||
+        node.length === 0 ||
+        Number.isNaN(node)) {
         return;
       }