From 440c4566ae5afef73aaa4f13a40a7e5d69187f50 Mon Sep 17 00:00:00 2001
From: Vince Speelman <v@vinspee.me>
Date: Thu, 29 Aug 2013 10:59:02 -0400
Subject: [PATCH] Add tint-shade-stack color stack

allow users to create a stack that includes both shaded and tinted versions of
a color.
---
 compass/stylesheets/toolkit/_colours.scss | 29 ++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/compass/stylesheets/toolkit/_colours.scss b/compass/stylesheets/toolkit/_colours.scss
index 7d77746..78102dc 100644
--- a/compass/stylesheets/toolkit/_colours.scss
+++ b/compass/stylesheets/toolkit/_colours.scss
@@ -60,6 +60,33 @@ $colour-stack-amounts: $color-stack-amounts !default;
   }
 }
 
+@function conjoin($lists, $separator: auto) {
+  $return: ();
+  @each $list in $lists {
+    $return: join($return, $list, $separator);
+  }
+  @return $return;
+}
+
+@function tint-shade-stack($colour, $amounts...) {
+  @if length($amounts) > 0 {
+    $shaded: colour-stack($colour, black, $amounts);
+    $shaded-short: conjoin(nth($shaded, 2) nth($shaded, 3));
+    $tinted: colour-stack($colour, white, $amounts);
+    $tinted-short: conjoin(nth($tinted, 2) nth($shaded, 3) nth($tinted, 4));
+    $tint-shade-stack: join($shaded-short, $tinted-short);
+    @return join($colour, $tint-shade-stack);
+  }
+  @else {
+    $shaded: colour-stack($colour, black);
+    $shaded-short: conjoin(nth($shaded, 2) nth($shaded, 3));
+    $tinted: colour-stack($colour, white);
+    $tinted-short: conjoin(nth($tinted, 2) nth($tinted, 3) nth($tinted, 4));
+    $tint-shade-stack: join($shaded-short, $tinted-short);
+    @return join($colour, $tint-shade-stack);
+  }
+}
+
 //////////////////////////////
 // Creates an even scale from one color to another
 //////////////////////////////
@@ -99,4 +126,4 @@ $colour-scale-shades: $color-scale-shades !default;
   }
 
   @return $list;
-}
\ No newline at end of file
+}