Issue 301 - jshydra: Handle for .. of ..

scripts/abprewrite.js

 // This script rewrites AST to be compatible with JavaScript 1.5 and decompiles
 // the modified tree then
 
 include("../scripts/astDecompile.js");
 include("../utils/beautify.js");
 
 let headerPrinted = false;
 
 // See https://developer.mozilla.org/en-US/docs/SpiderMonkey/Parser_API for
 // AST structure.
@@ skipping 302 matching lines @@
   ast.consequent = ensureBlock(ast.consequent);
   if (ast.alternate && ast.alternate.type != "IfStatement")
     ast.alternate = ensureBlock(ast.alternate);
   return ast;
 }
 
 function modifyForInStatement(ast)
 {
   if (ast.each)
   {
-    // Convert "for each" loops:
-    // for each (var foo in fooList)
-    // {
-    //   ...
-    // }
-    //
-    // Change into:
-    // for (var _loopIndex44 = 0; _loopIndex44 < fooList.length; ++_loopIndex44)
-    // {
-    //   var foo = fooList[_loopIndex44];
-    //   ...
-    // }
-    let loopIndex = Identifier("_loopIndex" + options.varIndex++);
-
-    let block = ensureBlock(ast.body);
-    if (ast.left.type == "VariableDeclaration")
-      block.body.unshift(VariableDeclaration(ast.left.declarations[0].id, Member(ast.right, loopIndex, true)));
-    else
-      block.body.unshift(Assignment(ast.left, Member(ast.right, loopIndex, true)));
-
-    return {
-      type: "ForStatement",
-      init: VariableDeclaration(loopIndex, 0),
-      test: LogicalExpression(loopIndex, "<", Member(ast.right, "length", false)),
-      update: IncExpression(loopIndex),
-      body: block
-    };
+    print("Use for (.. of ..) instead of for each (..)!\n");
+    throw new Error("Use for (.. of ..) instead of for each (..)!");
   }
 
   // Make sure that the loop body is always wrapped in a block
   ast.body = ensureBlock(ast.body);
 
   return ast;
 }
 
+function modifyForOfStatement(ast)
+{
+  // Convert "for of" loops:
+  // for (var foo of fooList)
+  // {
+  //   ...
+  // }
+  //
+  // Change into:
+  // for (var _loopIndex44 = 0; _loopIndex44 < fooList.length; ++_loopIndex44)
+  // {
+  //   var foo = fooList[_loopIndex44];
+  //   ...
+  // }
+  let loopIndex = Identifier("_loopIndex" + options.varIndex++);
+
+  let block = ensureBlock(ast.body);
+  if (ast.left.type == "VariableDeclaration")
+    block.body.unshift(VariableDeclaration(ast.left.declarations[0].id, Member(ast.right, loopIndex, true)));
+  else
+    block.body.unshift(Assignment(ast.left, Member(ast.right, loopIndex, true)));
+
+  return {
+    type: "ForStatement",
+    init: VariableDeclaration(loopIndex, 0),
+    test: LogicalExpression(loopIndex, "<", Member(ast.right, "length", false)),
+    update: IncExpression(loopIndex),
+    body: block
+  };
+}
+
 function modifyLetStatement(ast)
 {
   if (ast.body.type == "ForStatement" && ast.body.init == null)
   {
     // Convert back "for" loops written as "let" statements:
     // let (foo = 0) for (; foo < bar; ++foo)
     // {
     //   ...
     // }
     //
@@ skipping 100 matching lines @@
       callee: Member(options.generatorVar, "push"),
       arguments: [ast.argument]
     };
   }
   else
     return null;
 }
 
 process_js = function(ast, filename, args)
 {
-  for each (let arg in args.split(/\s+/))
+  for (let arg of args.split(/\s+/))
   {
     let match = /^(\w+)\s*=\s*(.*)/.exec(arg);
     if (match && typeof options[match[1]] == "boolean")
       options[match[1]] = (match[2] == "true");
     else if (match && typeof options[match[1]] == "string")
       options[match[1]] = match[2];
   }
 
   if (!headerPrinted)
   {
@@ skipping 48 matching lines @@
     let code = 'require.scopes["' + options.filename + '"] = (function() {\n' +
                'var exports = {};\n' +
                decompileAST(ast) +
                'return exports;\n' +
                '})();\n';
     _print(js_beautify(code, options));
   }
   else
     _print(js_beautify(decompileAST(ast), options));
 }