fix backtips shell implementation + add tests

Author: ichiriac

src/parser/expr.js

@@ -96,14 +96,9 @@ module.exports = function(api, tokens, EOF) {
           }
 
         case '`':
-          var expr = null;
+          // https://github.com/php/php-src/blob/master/Zend/zend_language_parser.y#L1048
           var result = this.node('sys');
-          if (this.next().token === tokens.T_ENCAPSED_AND_WHITESPACE) {
-            expr = this.text();
-            this.next().expect('`').next();
-          } else if (this.token !== '`' ) {
-            expr = this.read_encaps_list();
-          }
+          var expr = this.next().read_encapsed_string('`');
           return result('shell', expr);
 
         case tokens.T_LIST:

src/parser/scalar.js

@@ -170,11 +170,5 @@ module.exports = function(api, tokens, EOF) {
       this.next();
       return ['magic', '@todo:' + name];
     }
-    /**
-     * @todo
-     */
-    ,read_encaps_list: function() {
-      return this.next().token;
-    }
   };
 };

test/parser/expr.parser

@@ -1,5 +1,11 @@
 Test expr parser
 --PASS--
+class foo {
+	function aa() {
+		$parent_resource = " in '$this->parent->template_resource}'";
+	}
+}
+--PASS--
 $a = 1 + 2;
 $a++;
 $a--;
@@ -41,11 +47,20 @@ $b = @eval($arg);
 --PASS--
 $a = (int)$b;
 $a = (double)$b;
+$a = (unset)$b;
+$a = (bool)$b;
 $a = (string)$b;
 $a = (array)$b;
 $a = (object)$b;
 print 'done';
 exit(0);
+exit;
+--PASS--
+$var = new class extends foo {
+};
+list(list($a, $b), $c) = [
+  [1, 2], 3
+];
 --PASS--
 echo "test: {$this->test->foo}";
 $var = &new foo();
@@ -58,8 +73,4 @@ $var .= $a;
 $var &= $a;
 $var |= $a;
 --PASS--
-class foo {
-	function aa() {
-		$parent_resource = " in '$this->parent->template_resource}'";
-	}
-}
+$exec = `pstree -ap $process {$foo->bar}`;