WIP replacing direct access tpl_vars with proper getter/setters.

src/Compile/Tag/Assign.php

@@ -88,7 +88,7 @@ class Assign extends Base
         }
         if (isset($parameter[ 'smarty_internal_index' ])) {
             $output =
-                "<?php \$_tmp_array = isset(\$_smarty_tpl->tpl_vars[{$_var}]) ? \$_smarty_tpl->tpl_vars[{$_var}]->value : array();\n";
+                "<?php \$_tmp_array = \$_smarty_tpl->getValue({$_var}) ?? [];\n";
             $output .= "if (!(is_array(\$_tmp_array) || \$_tmp_array instanceof ArrayAccess)) {\n";
             $output .= "settype(\$_tmp_array, 'array');\n";
             $output .= "}\n";

src/Compile/Tag/ForeachTag.php

@@ -88,14 +88,14 @@ class ForeachTag extends ForeachSection {
 		$from = $_attr['from'];
 		$item = $compiler->getId($_attr['item']);
 		if ($item === false) {
-			$item = $compiler->getVariableName($_attr['item']);
+			$item = $this->getVariableName($_attr['item']);
 		}
 		$key = $name = null;
 		$attributes = ['item' => $item];
 		if (isset($_attr['key'])) {
 			$key = $compiler->getId($_attr['key']);
 			if ($key === false) {
-				$key = $compiler->getVariableName($_attr['key']);
+				$key = $this->getVariableName($_attr['key']);
 			}
 			$attributes['key'] = $key;
 		}
@@ -108,7 +108,7 @@ class ForeachTag extends ForeachSection {
 				$compiler->trigger_template_error("'{$a}' attribute/variable has illegal value", null, true);
 			}
 		}
-		$fromName = $compiler->getVariableName($_attr['from']);
+		$fromName = $this->getVariableName($_attr['from']);
 		if ($fromName) {
 			foreach (['item', 'key'] as $a) {
 				if (isset($attributes[$a]) && $attributes[$a] === $fromName) {
@@ -251,6 +251,22 @@ class ForeachTag extends ForeachSection {
 		return $output;
 	}
 
+	/**
+	 * Get variable name from string
+	 *
+	 * @param string $input
+	 *
+	 * @return bool|string
+	 *
+	 * @TODO: this may no longer work if we add a getter for tpl_vars, recheck this!
+	 */
+	private function getVariableName($input) {
+		if (preg_match('~^[$]_smarty_tpl->tpl_vars\[[\'"]*([0-9]*[a-zA-Z_]\w*)[\'"]*\]->value$~', $input, $match)) {
+			return $match[1];
+		}
+		return false;
+	}
+
 	/**
 	 * Compiles code for to restore saved template variables
 	 *

src/Compiler/Template.php

@@ -514,7 +514,7 @@ class Template extends BaseCompiler {
 					false
 				)->nocache;
 		}
-		return '$_smarty_tpl->tpl_vars[' . $variable . ']->value';
+		return '$_smarty_tpl->getValue(' . $variable . ')';
 	}
 
 	/**
@@ -758,20 +758,6 @@ class Template extends BaseCompiler {
 		return false;
 	}
 
-	/**
-	 * Get variable name from string
-	 *
-	 * @param string $input
-	 *
-	 * @return bool|string
-	 */
-	public function getVariableName($input) {
-		if (preg_match('~^[$]_smarty_tpl->tpl_vars\[[\'"]*([0-9]*[a-zA-Z_]\w*)[\'"]*\]->value$~', $input, $match)) {
-			return $match[1];
-		}
-		return false;
-	}
-
 	/**
 	 * Set nocache flag in variable or create new variable
 	 *

src/Data.php

@@ -304,6 +304,15 @@ abstract class Data
 		return new UndefinedVariable;
 	}
 
+	/**
+	 * Returns the value of the Smarty\Variable given by $varName, or null if the variable does not exist.
+	 * @return mixed|null
+	 */
+	public function getValue($varName) {
+		$variable = $this->_getVariable($varName);
+		return isset($variable) ? $variable->getValue() : null;
+	}
+
     /**
      * Follow the parent chain an merge template and config variables
      *

src/Parser/TemplateParser.y

@@ -199,7 +199,7 @@ class TemplateParser
      *
      * @return Tag
      */
-    public function mergePrefixCode($code)
+    private function mergePrefixCode($code)
     {
         $tmp = '';
         foreach ($this->compiler->prefix_code as $preCode) {
@@ -626,6 +626,16 @@ expr(res)        ::= ternary(v). {
     res = v;
 }
 
+		// ++$a / --$a
+expr(res)	::= INCDEC(i2) DOLLARID(i). {
+	res = '$_smarty_tpl->_getVariable(\''. substr(i,1) .'\')->preIncDec(\'' . i2 . '\')';
+}
+
+		// $a++ / $a--
+expr(res)	::= DOLLARID(i) INCDEC(i2). {
+	res = '$_smarty_tpl->_getVariable(\''. substr(i,1) .'\')->postIncDec(\'' . i2 . '\')';
+}
+
                  // resources/streams
 expr(res)        ::= DOLLARID(i) COLON ID(i2). {
     res = '$_smarty_tpl->getStreamVariable(\''.substr(i,1).'://' . i2 . '\')';
@@ -839,7 +849,7 @@ variable(res)    ::= varindexed(vi). {
 
                   // variable with property
 variable(res)    ::= varvar(v) AT ID(p). {
-    res = '$_smarty_tpl->tpl_vars['. v .']->'.p;
+    res = '$_smarty_tpl->_getVariable('. v .')->'.p;
 }
 
                   // object
@@ -1260,7 +1270,7 @@ doublequotedcontent(res)           ::=  BACKTICK expr(e) BACKTICK. {
 }
 
 doublequotedcontent(res)           ::=  DOLLARID(i). {
-    res = new Code('(string)$_smarty_tpl->tpl_vars[\''. substr(i,1) .'\']->value');
+    res = new Code('(string)$_smarty_tpl->getValue(\''. substr(i,1) .'\')');
 }
 
 doublequotedcontent(res)           ::=  LDEL variable(v) RDEL. {

src/Smarty.php

@@ -1017,7 +1017,7 @@ class Smarty extends \Smarty\TemplateBase
         $tpl = new \Smarty\Template($template, $this, null, $cache_id, $compile_id, null, null);
         $tpl->templateId = $_templateId;
 
-        $tpl->parent = $parent ? $parent : $this;
+        $tpl->parent = $parent ?: $this;
         // fill data if present
         if (!empty($data) && is_array($data)) {
             // set up variable values

src/TemplateBase.php

@@ -159,7 +159,7 @@ abstract class TemplateBase extends Data {
 		} else {
 			// get template object
 			$saveVars = false;
-			$template = $smarty->createTemplate($template, $cache_id, $compile_id, $parent ? $parent : $this, false);
+			$template = $smarty->createTemplate($template, $cache_id, $compile_id, $parent ?: $this, false);
 			if ($this->_objType === 1) {
 				// set caching in template object
 				$template->caching = $this->caching;

src/Variable.php

@@ -19,6 +19,13 @@ class Variable
      */
     public $value = null;
 
+	/**
+	 * @param mixed|null $value
+	 */
+	public function setValue($value): void {
+		$this->value = $value;
+	}
+
     /**
      * if true any output of this variable will be not cached
      *
@@ -26,6 +33,13 @@ class Variable
      */
     public $nocache = false;
 
+	/**
+	 * @param bool $nocache
+	 */
+	public function setNocache(bool $nocache): void {
+		$this->nocache = $nocache;
+	}
+
     /**
      * create Smarty variable object
      *
@@ -51,4 +65,49 @@ class Variable
     {
         return (string)$this->value;
     }
+
+	/**
+	 * Handles ++$a and --$a in templates.
+	 *
+	 * @param $operator '++' or '--', defaults to '++'
+	 *
+	 * @return int|mixed
+	 * @throws Exception
+	 */
+	public function preIncDec($operator = '++') {
+		if ($operator == '--') {
+			return --$this->value;
+		} elseif ($operator == '++') {
+			return ++$this->value;
+		} else {
+			throw new Exception("Invalid incdec operator. Use '--' or '++'.");
+		}
+		return $this->value;
+	}
+
+	/**
+	 * Handles $a++ and $a-- in templates.
+	 *
+	 * @param $operator '++' or '--', defaults to '++'
+	 *
+	 * @return int|mixed
+	 * @throws Exception
+	 */
+	public function postIncDec($operator = '++') {
+		if ($operator == '--') {
+			return $this->value--;
+		} elseif ($operator == '++') {
+			return $this->value++;
+		} else {
+			throw new Exception("Invalid incdec operator. Use '--' or '++'.");
+		}
+	}
+
+	/**
+	 * @return bool
+	 */
+	public function isNocache(): bool {
+		return $this->nocache;
+	}
+
 }

tests/UnitTests/TemplateSource/TagTests/If/CompileIfTest.php

@@ -165,7 +165,7 @@ class CompileIfTest extends PHPUnit_Smarty
         $this->smarty->assign($var, $value, true);
         $this->smarty->assign($var . '2', $value);
         $this->assertEquals($result, $this->strip($this->smarty->fetch('run_code_caching.tpl')),
-                            "testIfNocahe - {$code} - {$testName}");
+                            "testIfNocache - {$code} - {$testName}");
     }
 
     /*