- new feature/bugfix {foreach}{section} add 'properties' attribute to force compilation of loop properties

see NEW_FEATURES.txt https://github.com/smarty-php/smarty/issues/189

NEW_FEATURES.txt

@@ -4,6 +4,28 @@ This file contains a brief description of new features which have been added to
 
 Smarty 3.1.30
 
+    Loop optimization {foreach} and {section}
+    =========================================
+    Smarty does optimize the {foreach} and {section} loops by removing code for not needed loop
+    properties.
+    The compiler collects needed properties by scanning the current template for $item@property,
+    $smarty.foreach.name.property and $smarty.section.name.property.
+    The compiler does not know if additional properties will be needed outside the current template scope.
+    Additional properties can be generated by adding them with the property attribute.
+
+    Example:
+        index.tpl
+        {foreach $from as $item properties=[iteration, index]}
+            {include 'sub.tpl'}
+            {$item.total}
+        {/foreach}
+
+        sub.tpl
+        {$item.index} {$item.iteration} {$item.total}
+
+    In above example code for the 'total' property is automatically generated as $item.total is used in
+    index.tpl. Code for 'iteration' and 'index' must be added with properties=[iteration, index].
+
     New tag {make_nocache}
     ======================
     Syntax: {make_nocache $foo}

change_log.txt

@@ -1,7 +1,9 @@
  ===== 3.1.30-dev ===== (xx.xx.xx)
  20.02.2016
   - bugfix {strip} must keep space between hmtl tags. Broken by changes of 10.2.2016 https://github.com/smarty-php/smarty/issues/184
-  
+  - new feature/bugfix  {foreach}{section} add 'properties' attribute to force compilation of loop properties
+    see NEW_FEATURES.txt https://github.com/smarty-php/smarty/issues/189 
+    
  19.02.2016
   - revert output buffer flushing on display, echo content again because possible problems when PHP files had 
     characters (newline} after ?> at file end https://github.com/smarty-php/smarty/issues/187

libs/Smarty.class.php

@@ -121,7 +121,7 @@ class Smarty extends Smarty_Internal_TemplateBase
     /**
      * smarty version
      */
-    const SMARTY_VERSION = '3.1.30-dev/46';
+    const SMARTY_VERSION = '3.1.30-dev/47';
 
     /**
      * define variable scopes

libs/sysplugins/smarty_internal_compile_foreach.php

@@ -30,7 +30,7 @@ class Smarty_Internal_Compile_Foreach extends Smarty_Internal_Compile_Private_Fo
      * @var array
      * @see Smarty_Internal_CompileBase
      */
-    public $optional_attributes = array('name', 'key');
+    public $optional_attributes = array('name', 'key', 'properties');
 
     /**
      * Attribute definition: Overwrites base class.
@@ -137,6 +137,24 @@ class Smarty_Internal_Compile_Foreach extends Smarty_Internal_Compile_Private_Fo
         if (!empty($this->matchResults[ 'named' ])) {
             $namedAttr = $this->matchResults[ 'named' ];
         }
+        if (isset($_attr[ 'properties' ]) && preg_match_all("/['](.*?)[']/", $_attr[ 'properties' ], $match)) {
+            foreach ($match[ 1 ] as $prop) {
+                if (in_array($prop, $this->itemProperties)) {
+                    $itemAttr[ $prop ] = true;
+                } else {
+                    $compiler->trigger_template_error("Invalid property '{$prop}'", null, true);
+                }
+            }
+            if ($this->isNamed) {
+                foreach ($match[ 1 ] as $prop) {
+                    if (in_array($prop, $this->nameProperties)) {
+                        $nameAttr[ $prop ] = true;
+                    } else {
+                        $compiler->trigger_template_error("Invalid property '{$prop}'", null, true);
+                    }
+                }
+            }
+        }
         if (isset($itemAttr[ 'first' ])) {
             $itemAttr[ 'index' ] = true;
         }

libs/sysplugins/smarty_internal_compile_section.php

@@ -38,7 +38,7 @@ class Smarty_Internal_Compile_Section extends Smarty_Internal_Compile_Private_Fo
      * @var array
      * @see Smarty_Internal_CompileBase
      */
-    public $optional_attributes = array('start', 'step', 'max', 'show');
+    public $optional_attributes = array('start', 'step', 'max', 'show', 'properties');
 
     /**
      * counter
@@ -119,6 +119,15 @@ class Smarty_Internal_Compile_Section extends Smarty_Internal_Compile_Private_Fo
         if (!empty($this->matchResults[ 'named' ])) {
             $namedAttr = $this->matchResults[ 'named' ];
         }
+        if (isset($_attr[ 'properties' ]) && preg_match_all("/['](.*?)[']/", $_attr[ 'properties' ], $match)) {
+            foreach ($match[ 1 ] as $prop) {
+                if (in_array($prop, $this->nameProperties)) {
+                    $namedAttr[ $prop ] = true;
+                } else {
+                    $compiler->trigger_template_error("Invalid property '{$prop}'", null, true);
+                }
+            }
+        }
         $namedAttr[ 'index' ] = true;
         $output = "<?php\n";
         foreach ($_attr as $attr_name => $attr_value) {