box-size fix

package.json

@@ -4,6 +4,7 @@
   "description": "Flavor SCSS, bourbon.io based mixins & helpers",
   "main": "scss/flavor.scss",
   "scripts": {
+    "pretest": "changelog && npm run readme",
     "readme": "pkg-2-readme package.json > README.md -t \"./pkg-2-readme.template.md\" && echo 'README.md file built'",
     "test": "sass-lint -c scss-lint.yml -v -q"
   },
@@ -30,4 +31,4 @@
     "bourbon": "^5.0.0",
     "sass-lint": "^1.12.1"
   }
-}
+}

scss/mixins/_box.scss

@@ -25,8 +25,17 @@ $bound-box-sizes: array-append((none), $css-default-modes);
   -moz-box-shadow: $shadows;
   box-shadow: $shadows;
 }
-@mixin box-size($options, $height-fallback: true) {
-  $settings: ( width: null, height: null, min-width: null, min-height: null, max-width: null, max-height: null );
+@mixin box-size($options) {
+  $settings: (
+    width: null,
+    height: null,
+    min-width: null,
+    min-height: null,
+    max-width: null,
+    max-height: null
+    height-fallback: true
+  );
+
   @if is-object($options) {
     $settings:extend($settings, $options);
   }
@@ -72,6 +81,8 @@ $bound-box-sizes: array-append((none), $css-default-modes);
     }
   }
 
+  $height-fallback: map-get($settings, height-fallback);
+
   $height: map-get($settings, height);
   @if $height-fallback == true and is-defined($width) and not is-defined($height) {
     $height: $width;