#205 - implement byref decorator

Author: ichiriac

src/ast.js

@@ -35,6 +35,7 @@ const Position = require("./ast/position");
  *   - [Expression](#expression)
  *     - [Entry](#entry)
  *     - [Closure](#closure)
+ *     - [ByRef](#byref)
  *     - [Silent](#silent)
  *     - [RetIf](#retif)
  *     - [New](#new)
@@ -473,6 +474,7 @@ AST.prototype.checkNodes = function() {
   require("./ast/block"),
   require("./ast/boolean"),
   require("./ast/break"),
+  require("./ast/byref"),
   require("./ast/call"),
   require("./ast/case"),
   require("./ast/cast"),

src/ast/byref.js

@@ -0,0 +1,20 @@
+/**
+ * Copyright (C) 2018 Glayzzle (BSD3 License)
+ * @authors https://github.com/glayzzle/php-parser/graphs/contributors
+ * @url http://glayzzle.com
+ */
+"use strict";
+
+const Expression = require("./expression");
+const KIND = "byref";
+
+/**
+ * Passing by Reference - so the function can modify the variable
+ * @constructor ByRef
+ * @extends {Expression}
+ * @property {expr} what
+ */
+module.exports = Expression.extends(KIND, function ByRef(what, docs, location) {
+  Expression.apply(this, [KIND, docs, location]);
+  this.what = what;
+});

src/ast/variable.js

@@ -15,27 +15,23 @@ const KIND = "variable";
  * @extends {Expression}
  * @example
  * // PHP code :
- * &$foo
+ * $foo
  * // AST output
  * {
  *  "kind": "variable",
  *  "name": "foo",
- *  "byref": true,
  *  "curly": false
  * }
  * @property {String|Node} name The variable name (can be a complex expression when the name is resolved dynamically)
- * @property {boolean} byref Indicate if the variable reference is used, ex `&$foo`
  * @property {boolean} curly Indicate if the name is defined between curlies, ex `${foo}`
  */
 module.exports = Expression.extends(KIND, function Variable(
   name,
-  byref,
   curly,
   docs,
   location
 ) {
   Expression.apply(this, [KIND, docs, location]);
   this.name = name;
-  this.byref = byref || false;
   this.curly = curly || false;
 });

src/parser/array.js

@@ -71,13 +71,16 @@ module.exports = {
       return this.node("noop")();
     }
     if (this.token === "&") {
-      return this.next().read_variable(true, false, true);
+      return this.node("byref")(this.next().read_variable(true, false));
     } else {
       const entry = this.node(ArrayEntry);
       const expr = this.read_expr();
       if (this.token === this.tok.T_DOUBLE_ARROW) {
         if (this.next().token === "&") {
-          return entry(expr, this.next().read_variable(true, false, true));
+          return entry(
+            expr,
+            this.node("byref")(this.next().read_variable(true, false))
+          );
         } else {
           return entry(expr, this.read_expr());
         }

src/parser/function.js

@@ -144,16 +144,14 @@ module.exports = {
    * ```
    */
   read_lexical_var: function() {
-    const result = this.node("variable");
-    let isRef = false;
     if (this.token === "&") {
-      isRef = true;
-      this.next();
+      return this.node("byref")(this.next().read_lexical_var());
     }
+    const result = this.node("variable");
     this.expect(this.tok.T_VARIABLE);
     const name = this.text().substring(1);
     this.next();
-    return result(name, isRef, false);
+    return result(name, false);
   },
   /**
    * reads a list of parameters

src/parser/scalar.js

@@ -206,7 +206,7 @@ module.exports = {
         // check if lookup an offset
         // https://github.com/php/php-src/blob/master/Zend/zend_language_parser.y#L1243
         if (this.token === "[") {
-          name = name(varName, false, false);
+          name = name(varName, false);
           node = this.node("offsetlookup");
           offset = this.next().read_expr();
           this.expect("]") && this.next();
@@ -218,7 +218,7 @@ module.exports = {
         name = this.read_expr();
       }
       this.expect("}") && this.next();
-      result = result("variable", name, false, true);
+      result = result("variable", name, true);
     } else if (this.token === this.tok.T_CURLY_OPEN) {
       // expression
       // https://github.com/php/php-src/blob/master/Zend/zend_language_parser.y#L1246
@@ -230,7 +230,7 @@ module.exports = {
       // plain variable
       // https://github.com/php/php-src/blob/master/Zend/zend_language_parser.y#L1231
       result.destroy();
-      result = this.read_simple_variable(false);
+      result = this.read_simple_variable();
 
       // https://github.com/php/php-src/blob/master/Zend/zend_language_parser.y#L1233
       if (this.token === "[") {

src/parser/utils.js

@@ -104,9 +104,9 @@ module.exports = {
       if (this.expect(this.tok.T_VARIABLE)) {
         const name = this.text().substring(1);
         this.next();
-        variable = variable(name, false, false);
+        variable = variable(name, false);
       } else {
-        variable = variable("#ERR", false, false);
+        variable = variable("#ERR", false);
       }
       if (this.token === "=") {
         return node(variable, this.next().read_expr());

src/parser/variable.js

@@ -22,18 +22,17 @@ module.exports = {
    *  $var->func()->property    // chained calls
    * ```
    */
-  read_variable: function(read_only, encapsed, byref) {
+  read_variable: function(read_only, encapsed) {
     let result;
 
     // check the byref flag
-    if (!byref && this.token === "&") {
-      byref = true;
-      this.next();
+    if (this.token === "&") {
+      return this.node("byref")(this.next().read_variable(read_only, encapsed));
     }
 
     // reads the entry point
     if (this.is([this.tok.T_VARIABLE, "$"])) {
-      result = this.read_reference_variable(encapsed, byref);
+      result = this.read_reference_variable(encapsed);
     } else if (
       this.is([
         this.tok.T_NS_SEPARATOR,
@@ -85,7 +84,7 @@ module.exports = {
     const result = this.node("staticlookup");
     let offset, name;
     if (this.next().is([this.tok.T_VARIABLE, "$"])) {
-      offset = this.read_reference_variable(encapsed, false);
+      offset = this.read_reference_variable(encapsed);
     } else if (
       this.token === this.tok.T_STRING ||
       this.token === this.tok.T_CLASS ||
@@ -131,7 +130,7 @@ module.exports = {
           name = this.text().substring(1);
           this.next();
           what = this.node("encapsed")(
-            [what, inner(name, false, false)],
+            [what, inner(name, false)],
             null,
             "offset"
           );
@@ -151,7 +150,7 @@ module.exports = {
         what = this.node("variable");
         name = this.text().substring(1);
         this.next();
-        what = what(name, false, false);
+        what = what(name, false);
         break;
       case "$":
         what = this.node();
@@ -164,7 +163,7 @@ module.exports = {
         } else {
           // $obj->$$varname
           name = this.read_expr();
-          what = what("variable", name, false, false);
+          what = what("variable", name, false);
         }
         break;
       case "{":
@@ -264,7 +263,7 @@ module.exports = {
     } else if (this.token === this.tok.T_VARIABLE) {
       const name = this.text().substring(1);
       this.next();
-      offset = offset("variable", name, false, false);
+      offset = offset("variable", name, false);
     } else {
       this.expect([
         this.tok.T_STRING,
@@ -289,8 +288,8 @@ module.exports = {
    *  $foo[123]{1};   // gets the 2nd char from the 123 array entry
    * </code>
    */
-  read_reference_variable: function(encapsed, byref) {
-    let result = this.read_simple_variable(byref);
+  read_reference_variable: function(encapsed) {
+    let result = this.read_simple_variable();
     let offset;
     while (this.token != this.EOF) {
       const node = this.node();
@@ -311,7 +310,7 @@ module.exports = {
    *  simple_variable ::= T_VARIABLE | '$' '{' expr '}' | '$' simple_variable
    * ```
    */
-  read_simple_variable: function(byref) {
+  read_simple_variable: function() {
     let result = this.node("variable");
     let name;
     if (
@@ -321,35 +320,35 @@ module.exports = {
       // plain variable name
       name = this.text().substring(1);
       this.next();
-      result = result(name, byref, false);
+      result = result(name, false);
     } else {
       if (this.token === "$") this.next();
       // dynamic variable name
       switch (this.token) {
         case "{": {
           const expr = this.next().read_expr();
           this.expect("}") && this.next();
-          result = result(expr, byref, true);
+          result = result(expr, true);
           break;
         }
         case "$": // $$$var
           // @fixme check coverage here
-          result = result(this.read_simple_variable(false), byref, false);
+          result = result(this.read_simple_variable(), false);
           break;
         case this.tok.T_VARIABLE: {
           // $$var
           name = this.text().substring(1);
           const node = this.node("variable");
           this.next();
-          result = result(node(name, false, false), byref, false);
+          result = result(node(name, false), false);
           break;
         }
         default:
           this.error(["{", "$", this.tok.T_VARIABLE]);
           // graceful mode
           name = this.text();
           this.next();
-          result = result(name, byref, false);
+          result = result(name, false);
       }
     }
     return result;