Adding 'each .. of' syntax

packages/pug-code-gen/index.js

@@ -65,6 +65,7 @@ function Compiler(node, options) {
   this.mixins = {};
   this.dynamicMixins = false;
   this.eachCount = 0;
+  this.eachOfCount = 0;
   if (options.doctype) this.setDoctype(options.doctype);
   this.runtimeFunctionsUsed = [];
   this.inlineRuntimeFunctions = options.inlineRuntimeFunctions || false;
@@ -767,6 +768,37 @@ Compiler.prototype = {
     this.buf.push('  }\n}).call(this);\n');
   },
 
+  visitEachOf: function(each){
+    var valVarName = 'pug_val' + this.eachOfCount;
+    if (each.key) {
+      var keyVarName = 'pug_key' + this.eachOfCount
+    }
+    this.eachOfCount++;
+
+    this.buf.push(''
+      + '// iterate ' + each.obj + '\n'
+      + ';(function(){\n'
+      + '  var $$obj = ' + each.obj + ';\n'
+      + '  var $$l = 0;\n')
+    if (each.key) {
+      this.buf.push('  for (const [' + keyVarName + ', ' + valVarName + '] of $$obj) {\n');
+    } else {
+      this.buf.push('  for (const ' + valVarName + ' of $$obj) {\n');
+    }
+    this.buf.push('    $$l++;\n');
+    if (each.key) {
+      this.buf.push(''
+        + '    var ' + each.key + ' = ' + valVarName + ';'
+        + '    var ' + each.val + ' = ' + keyVarName + ';');
+    } else {
+      this.buf.push('    var ' + each.val + ' = ' + valVarName + ';')
+    }
+
+    this.visit(each.block, each);
+
+    this.buf.push('  }\n}).call(this);\n');
+  },
+
   /**
    * Visit `attrs`.
    *

packages/pug-lexer/index.js

@@ -971,6 +971,31 @@ Lexer.prototype = {
     }
   },
 
+  /**
+   * EachOf.
+   */
+
+  eachOf: function() {
+    var captures;
+    if (captures = /^(?:each|for) +\[?([a-zA-Z_$][\w$]*)(?: *, *([a-zA-Z_$][\w$]*))?\]? * of *([^\n]+)/.exec(this.input)) {
+      this.consume(captures[0].length);
+      var tok = this.tok('eachOf', captures[1]);
+      tok.key = captures[2] || null;
+      this.incrementColumn(captures[0].length - captures[3].length);
+      this.assertExpression(captures[3])
+      tok.code = captures[3];
+      this.incrementColumn(captures[3].length);
+      this.tokens.push(this.tokEnd(tok));
+      return true;
+    }
+    if (captures = /^- *(?:each|for) +([a-zA-Z_$][\w$]*)(?: *, *([a-zA-Z_$][\w$]*))? +of +([^\n]+)/.exec(this.input)) {
+      this.error(
+        'MALFORMED_EACH',
+        'Pug each and for should not be prefixed with a dash ("-"). They are pug keywords and not part of JavaScript.'
+      );
+    }
+  },
+
   /**
    * Code.
    */
@@ -1485,6 +1510,7 @@ Lexer.prototype = {
       || this.callLexerFunction('mixin')
       || this.callLexerFunction('call')
       || this.callLexerFunction('conditional')
+      || this.callLexerFunction('eachOf')
       || this.callLexerFunction('each')
       || this.callLexerFunction('while')
       || this.callLexerFunction('tag')

packages/pug-lexer/test/check-lexer-functions.test.js

@@ -23,6 +23,7 @@ var lexerFunctions = {
   doctype: true,
   dot: true,
   each: true,
+  eachOf: true,
   eos: true,
   endInterpolation: true,
   extends: true,

packages/pug-parser/index.js

@@ -234,6 +234,8 @@ Parser.prototype = {
         return this.parseDot();
       case 'each':
         return this.parseEach();
+      case 'eachOf':
+        return this.parseEachOf();
       case 'code':
         return this.parseCode();
       case 'blockcode':
@@ -761,6 +763,20 @@ loop:
     return node;
   },
 
+  parseEachOf: function(){
+    var tok = this.expect('eachOf');
+    var node = {
+      type: 'EachOf',
+      obj: tok.code,
+      val: tok.val,
+      key: tok.key,
+      block: this.block(),
+      line: tok.loc.start.line,
+      column: tok.loc.start.column,
+      filename: this.filename
+    };
+    return node;
+  },
   /**
    * 'extends' name
    */

packages/pug-walk/index.js

@@ -56,6 +56,11 @@ function walkAST(ast, before, after, options) {
         ast.alternate = walkAST(ast.alternate, before, after, options);
       }
       break;
+    case 'EachOf':
+      if (ast.block) {
+        ast.block = walkAST(ast.block, before, after, options);
+      }
+      break;
     case 'Conditional':
       if (ast.consequent) {
         ast.consequent = walkAST(ast.consequent, before, after, options);