Merge pull request leafo#69 from robocoder/issue-68

@if and @while directives should treat null condition like false

Author: leafo

scss.inc.php

@@ -54,6 +54,7 @@ class scssc {
 
 	static public $true = array("keyword", "true");
 	static public $false = array("keyword", "false");
+	static public $null = array("null");
 
 	static public $defaultValue = array("keyword", "");
 	static public $selfSelector = array("self");
@@ -575,12 +576,12 @@ protected function compileChild($child, $out) {
 			break;
 		case "if":
 			list(, $if) = $child;
-			if ($this->reduce($if->cond, true) != self::$false) {
+			if (($cond = $this->reduce($if->cond, true)) != self::$false && $cond != self::$null) {
 				return $this->compileChildren($if->children, $out);
 			} else {
 				foreach ($if->cases as $case) {
 					if ($case->type == "else" ||
-						$case->type == "elseif" && ($this->reduce($case->cond) != self::$false))
+						$case->type == "elseif" && (($cond = $this->reduce($case->cond)) != self::$false) && $cond != self::$null)
 					{
 						return $this->compileChildren($case->children, $out);
 					}
@@ -602,7 +603,7 @@ protected function compileChild($child, $out) {
 			break;
 		case "while":
 			list(,$while) = $child;
-			while ($this->reduce($while->cond, true) != self::$false) {
+			while (($cond = $this->reduce($while->cond, true)) != self::$false && $cond != self::$null) {
 				$ret = $this->compileChildren($while->children, $out);
 				if ($ret) return $ret;
 			}

tests/inputs/if.scss

@@ -16,6 +16,9 @@ div {
 pre {
     val-1: conds(true);
     val-2: conds(false);
+    val-3: conds(null);
+    val-4: conds(1);
+    val-5: conds(0);
 }
 
 

tests/inputs/looping.scss

@@ -44,3 +44,8 @@ pre {
 
 }
 
+$j: null;
+@while $j {
+  .item { width: 2em; }
+  $j: false;
+}

tests/outputs/if.css

@@ -3,7 +3,10 @@ div {
 
 pre {
   val-1: "red";
-  val-2: "blue"; }
+  val-2: "blue";
+  val-3: "blue";
+  val-4: "red";
+  val-5: "red"; }
 
 span {
   color: blue;