From 554a03a2148139c2623caf9bf39aa89811b34d71 Mon Sep 17 00:00:00 2001
From: Natalie Weizenbaum <nweiz@google.com>
Date: Fri, 6 Oct 2023 14:51:18 -0700
Subject: [PATCH] [Color 4] Add tests for oklab() (#1938)

---
 .../color/hsl/error/one_arg.hrx               |   8 +-
 .../color/hwb/error/four_args.hrx             |   6 +-
 .../color/hwb/error/one_arg.hrx               |   8 +-
 .../color/hwb/error/three_args.hrx            |   6 +-
 spec/core_functions/color/lab/error.hrx       |   6 +-
 spec/core_functions/color/oklab/README.md     |   2 +
 spec/core_functions/color/oklab/_utils.scss   |  27 ++
 spec/core_functions/color/oklab/alpha.hrx     | 120 ++++++++
 spec/core_functions/color/oklab/error.hrx     | 259 ++++++++++++++++++
 spec/core_functions/color/oklab/no_alpha.hrx  | 189 +++++++++++++
 spec/core_functions/color/oklab/options.yml   |   3 +
 .../color/oklab/special_functions.hrx         | 142 ++++++++++
 .../color/rgb/error/one_arg.hrx               |   8 +-
 13 files changed, 763 insertions(+), 21 deletions(-)
 create mode 100644 spec/core_functions/color/oklab/README.md
 create mode 100644 spec/core_functions/color/oklab/_utils.scss
 create mode 100644 spec/core_functions/color/oklab/alpha.hrx
 create mode 100644 spec/core_functions/color/oklab/error.hrx
 create mode 100644 spec/core_functions/color/oklab/no_alpha.hrx
 create mode 100644 spec/core_functions/color/oklab/options.yml
 create mode 100644 spec/core_functions/color/oklab/special_functions.hrx

diff --git a/spec/core_functions/color/hsl/error/one_arg.hrx b/spec/core_functions/color/hsl/error/one_arg.hrx
index b603b431dd..d511c26aa4 100644
--- a/spec/core_functions/color/hsl/error/one_arg.hrx
+++ b/spec/core_functions/color/hsl/error/one_arg.hrx
@@ -101,7 +101,7 @@ a {
 }
 
 <===> type/hue/error
-Error: $channels: Expected hue "foo" to be a number.
+Error: $channels: Expected hue channel to be a number, was "foo".
   ,
 2 |   b: hsl("foo" 100% 50%);
   |      ^^^^^^^^^^^^^^^^^^^
@@ -116,7 +116,7 @@ a {
 }
 
 <===> type/saturation/error
-Error: $channels: Expected saturation "foo" to be a number.
+Error: $channels: Expected saturation channel to be a number, was "foo".
   ,
 2 |   b: hsl(0 "foo" 50%);
   |      ^^^^^^^^^^^^^^^^
@@ -131,7 +131,7 @@ a {
 }
 
 <===> type/lightness/error
-Error: $channels: Expected lightness "foo" to be a number.
+Error: $channels: Expected lightness channel to be a number, was "foo".
   ,
 2 |   b: hsl(0 100% "foo");
   |      ^^^^^^^^^^^^^^^^^
@@ -146,7 +146,7 @@ a {
 }
 
 <===> quoted_var_slash/error
-Error: $channels: Expected lightness "var(--foo) / 0.4" to be a number.
+Error: $channels: Expected lightness channel to be a number, was "var(--foo) / 0.4".
   ,
 2 |   b: hsl(0 100% "var(--foo) / 0.4");
   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/spec/core_functions/color/hwb/error/four_args.hrx b/spec/core_functions/color/hwb/error/four_args.hrx
index 6600ef2038..3a26596ccb 100644
--- a/spec/core_functions/color/hwb/error/four_args.hrx
+++ b/spec/core_functions/color/hwb/error/four_args.hrx
@@ -3,7 +3,7 @@
 a {b: color.hwb("foo", 30%, 40%, 0.5)}
 
 <===> hue/type/error
-Error: Expected hue "foo" to be a number.
+Error: Expected hue channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb("foo", 30%, 40%, 0.5)}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -36,7 +36,7 @@ Error: $hue: var(--c) is not a number.
 a {b: color.hwb(0, "foo", 40%, 0.5)}
 
 <===> whiteness/type/error
-Error: Expected whiteness "foo" to be a number.
+Error: Expected whiteness channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb(0, "foo", 40%, 0.5)}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -135,7 +135,7 @@ Error: $whiteness: var(--c) is not a number.
 a {b: color.hwb(0, 30%, "foo", 0.5)}
 
 <===> blackness/type/error
-Error: Expected blackness "foo" to be a number.
+Error: Expected blackness channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb(0, 30%, "foo", 0.5)}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/spec/core_functions/color/hwb/error/one_arg.hrx b/spec/core_functions/color/hwb/error/one_arg.hrx
index 39cf839885..8740f3c491 100644
--- a/spec/core_functions/color/hwb/error/one_arg.hrx
+++ b/spec/core_functions/color/hwb/error/one_arg.hrx
@@ -87,7 +87,7 @@ Error: $channels: The hwb color space has 3 channels but (0 30% 40% 0.4) has 4.
 a {b: color.hwb("foo" 30% 40%)}
 
 <===> hue/type/error
-Error: $channels: Expected hue "foo" to be a number.
+Error: $channels: Expected hue channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb("foo" 30% 40%)}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -120,7 +120,7 @@ Error: $hue: var(--c) is not a number.
 a {b: color.hwb(0 "foo" 40%)}
 
 <===> whiteness/type/error
-Error: $channels: Expected whiteness "foo" to be a number.
+Error: $channels: Expected whiteness channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb(0 "foo" 40%)}
   |       ^^^^^^^^^^^^^^^^^^^^^^
@@ -219,7 +219,7 @@ Error: $whiteness: var(--c) is not a number.
 a {b: color.hwb(0 30% "foo")}
 
 <===> blackness/type/error
-Error: $channels: Expected blackness "foo" to be a number.
+Error: $channels: Expected blackness channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb(0 30% "foo")}
   |       ^^^^^^^^^^^^^^^^^^^^^^
@@ -367,7 +367,7 @@ Error: Expected numeric channels, got "hwb(0 0 0/var(--c))".
 a {b: color.hwb(0 30% "var(--foo) / 0.4")}
 
 <===> quoted_var_slash/error
-Error: $channels: Expected blackness "var(--foo) / 0.4" to be a number.
+Error: $channels: Expected blackness channel to be a number, was "var(--foo) / 0.4".
   ,
 2 | a {b: color.hwb(0 30% "var(--foo) / 0.4")}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/spec/core_functions/color/hwb/error/three_args.hrx b/spec/core_functions/color/hwb/error/three_args.hrx
index 558f605fa9..1d3b955595 100644
--- a/spec/core_functions/color/hwb/error/three_args.hrx
+++ b/spec/core_functions/color/hwb/error/three_args.hrx
@@ -3,7 +3,7 @@
 a {b: color.hwb("foo", 100%, 50%)}
 
 <===> hue/type/error
-Error: Expected hue "foo" to be a number.
+Error: Expected hue channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb("foo", 100%, 50%)}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -25,7 +25,7 @@ Error: argument `$hue` of `hwb($hue, $whiteness, $blackness)` must be a number
 a {b: color.hwb(0, "foo", 50%)}
 
 <===> whiteness/type/error
-Error: Expected whiteness "foo" to be a number.
+Error: Expected whiteness channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb(0, "foo", 50%)}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -47,7 +47,7 @@ Error: argument `$whiteness` of `hwb($hue, $whiteness, $blackness)` must be a nu
 a {b: color.hwb(0, 100%, "foo")}
 
 <===> blackness/type/error
-Error: Expected blackness "foo" to be a number.
+Error: Expected blackness channel to be a number, was "foo".
   ,
 2 | a {b: color.hwb(0, 100%, "foo")}
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/spec/core_functions/color/lab/error.hrx b/spec/core_functions/color/lab/error.hrx
index 8ef5bf1f08..27363ac64a 100644
--- a/spec/core_functions/color/lab/error.hrx
+++ b/spec/core_functions/color/lab/error.hrx
@@ -68,7 +68,7 @@ Error: $alpha: Expected 0.4px to have unit "%" or no units.
 a {b: lab(c 2 3)}
 
 <===> type/lightness/error
-Error: $channels: Expected lightness c to be a number.
+Error: $channels: Expected lightness channel to be a number, was c.
   ,
 1 | a {b: lab(c 2 3)}
   |       ^^^^^^^^^^
@@ -81,7 +81,7 @@ Error: $channels: Expected lightness c to be a number.
 a {b: lab(1% c 3)}
 
 <===> type/a/error
-Error: $channels: Expected a c to be a number.
+Error: $channels: Expected a channel to be a number, was c.
   ,
 1 | a {b: lab(1% c 3)}
   |       ^^^^^^^^^^^
@@ -94,7 +94,7 @@ Error: $channels: Expected a c to be a number.
 a {b: lab(1% 2 c)}
 
 <===> type/b/error
-Error: $channels: Expected b c to be a number.
+Error: $channels: Expected b channel to be a number, was c.
   ,
 1 | a {b: lab(1% 2 c)}
   |       ^^^^^^^^^^^
diff --git a/spec/core_functions/color/oklab/README.md b/spec/core_functions/color/oklab/README.md
new file mode 100644
index 0000000000..5117c908e1
--- /dev/null
+++ b/spec/core_functions/color/oklab/README.md
@@ -0,0 +1,2 @@
+Some of the same behavior tested for `lab()` applies to this function as well,
+but for terseness' sake isn't tested explicitly.
diff --git a/spec/core_functions/color/oklab/_utils.scss b/spec/core_functions/color/oklab/_utils.scss
new file mode 100644
index 0000000000..106fe41df4
--- /dev/null
+++ b/spec/core_functions/color/oklab/_utils.scss
@@ -0,0 +1,27 @@
+@use 'sass:color';
+@use 'sass:list';
+@use 'sass:meta';
+
+@function -real-channel($color, $channel) {
+  @if color.is-missing($color, $channel) {
+    @return none;
+  } @else {
+    @return color.channel($color, $channel);
+  }
+}
+
+@mixin inspect($color) {
+  a {
+    value: $color;
+    @if meta.type-of($color) == string {
+      type: string;
+    } @else {
+      channels: list.slash(
+        -real-channel($color, 'lightness')
+          -real-channel($color, 'a')
+          -real-channel($color, 'b'),
+        -real-channel($color, 'alpha')
+      );
+    }
+  }
+}
diff --git a/spec/core_functions/color/oklab/alpha.hrx b/spec/core_functions/color/oklab/alpha.hrx
new file mode 100644
index 0000000000..4f245830d1
--- /dev/null
+++ b/spec/core_functions/color/oklab/alpha.hrx
@@ -0,0 +1,120 @@
+<===> transparent/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(0 255 127 / 0));
+
+<===> transparent/output.css
+a {
+  value: oklab(0% 255 127 / 0);
+  channels: 0% 255 127 / 0;
+}
+
+<===>
+================================================================================
+<===> opaque/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 3 / 1));
+
+<===> opaque/output.css
+a {
+  value: oklab(1% 2 3);
+  channels: 1% 2 3 / 1;
+}
+
+<===>
+================================================================================
+<===> partial/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 3 / 0.4));
+
+<===> partial/output.css
+a {
+  value: oklab(1% 2 3 / 0.4);
+  channels: 1% 2 3 / 0.4;
+}
+
+<===>
+================================================================================
+<===> percent/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 3 / 40%));
+
+<===> percent/output.css
+a {
+  value: oklab(1% 2 3 / 0.4);
+  channels: 1% 2 3 / 0.4;
+}
+
+<===>
+================================================================================
+<===> named/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab($channels: 1% 2 3 / 0.4));
+
+<===> named/output.css
+a {
+  value: oklab(1% 2 3 / 0.4);
+  channels: 1% 2 3 / 0.4;
+}
+
+<===>
+================================================================================
+<===> slash_list/input.scss
+@use "sass:list";
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(list.slash(1% 2 3, 0.4)));
+
+<===> slash_list/output.css
+a {
+  value: oklab(1% 2 3 / 0.4);
+  channels: 1% 2 3 / 0.4;
+}
+
+<===>
+================================================================================
+<===> none/slash/b/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 none / 0.4));
+
+<===> none/slash/b/output.css
+a {
+  value: oklab(1% 2 none / 0.4);
+  channels: 1% 2 none / 0.4;
+}
+
+<===>
+================================================================================
+<===> none/slash/alpha/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 3 / none));
+
+<===> none/slash/alpha/output.css
+a {
+  value: oklab(1% 2 3 / none);
+  channels: 1% 2 3 / none;
+}
+
+<===>
+================================================================================
+<===> none/slash_list/b/input.scss
+@use 'sass:list';
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(list.slash(1% 2 none, 0.4)));
+
+<===> none/slash_list/b/output.css
+a {
+  value: oklab(1% 2 none / 0.4);
+  channels: 1% 2 none / 0.4;
+}
+
+<===>
+================================================================================
+<===> none/slash_list/alpha/input.scss
+@use 'sass:list';
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(list.slash(1% 2 3, none)));
+
+<===> none/slash_list/alpha/output.css
+a {
+  value: oklab(1% 2 3 / none);
+  channels: 1% 2 3 / none;
+}
diff --git a/spec/core_functions/color/oklab/error.hrx b/spec/core_functions/color/oklab/error.hrx
new file mode 100644
index 0000000000..b39e25c0d2
--- /dev/null
+++ b/spec/core_functions/color/oklab/error.hrx
@@ -0,0 +1,259 @@
+<===> unit/lightness/input.scss
+a {b: oklab(1px 2 3)}
+
+<===> unit/lightness/error
+Error: $lightness: Expected 1px to have unit "%" or no units.
+  ,
+1 | a {b: oklab(1px 2 3)}
+  |       ^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> unit/a/input.scss
+a {b: oklab(1% 2px 3)}
+
+<===> unit/a/error
+Error: $a: Expected 2px to have unit "%" or no units.
+  ,
+1 | a {b: oklab(1% 2px 3)}
+  |       ^^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> unit/b/input.scss
+a {b: oklab(1% 2 3px)}
+
+<===> unit/b/error
+Error: $b: Expected 3px to have unit "%" or no units.
+  ,
+1 | a {b: oklab(1% 2 3px)}
+  |       ^^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> unit/alpha/slash/input.scss
+a {b: oklab(1% 2 3/0.4px)}
+
+<===> unit/alpha/slash/error
+Error: $alpha: Expected 0.4px to have unit "%" or no units.
+  ,
+1 | a {b: oklab(1% 2 3/0.4px)}
+  |       ^^^^^^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> unit/alpha/slash_list/input.scss
+@use 'sass:list';
+a {b: oklab(list.slash(1% 2 3, 0.4px))}
+
+<===> unit/alpha/slash_list/error
+Error: $alpha: Expected 0.4px to have unit "%" or no units.
+  ,
+2 | a {b: oklab(list.slash(1% 2 3, 0.4px))}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+  input.scss 2:7  root stylesheet
+
+<===>
+================================================================================
+<===> type/lightness/input.scss
+a {b: oklab(c 2 3)}
+
+<===> type/lightness/error
+Error: $channels: Expected lightness channel to be a number, was c.
+  ,
+1 | a {b: oklab(c 2 3)}
+  |       ^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> type/a/input.scss
+a {b: oklab(1% c 3)}
+
+<===> type/a/error
+Error: $channels: Expected a channel to be a number, was c.
+  ,
+1 | a {b: oklab(1% c 3)}
+  |       ^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> type/b/input.scss
+a {b: oklab(1% 2 c)}
+
+<===> type/b/error
+Error: $channels: Expected b channel to be a number, was c.
+  ,
+1 | a {b: oklab(1% 2 c)}
+  |       ^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> type/alpha/slash_list/input.scss
+@use 'sass:list';
+a {b: oklab(list.slash(1% 2 3, c))}
+
+<===> type/alpha/slash_list/error
+Error: $channels: c is not a number.
+  ,
+2 | a {b: oklab(list.slash(1% 2 3, c))}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+  input.scss 2:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/bracketed/input.scss
+a {b: oklab([1% 2 3])}
+
+<===> list/bracketed/error
+Error: $channels: Expected an unbracketed list, was [1% 2 3]
+  ,
+1 | a {b: oklab([1% 2 3])}
+  |       ^^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/comma/input.scss
+a {b: oklab((1%, 2, 3))}
+
+<===> list/comma/error
+Error: $channels: Expected a space- or slash-separated list, was (1%, 2, 3)
+  ,
+1 | a {b: oklab((1%, 2, 3))}
+  |       ^^^^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/slash/three/input.scss
+@use 'sass:list';
+a {b: oklab(list.slash(1%, 2, 3))}
+
+<===> list/slash/three/error
+Error: $channels: Only 2 slash-separated elements allowed, but 3 were passed.
+  ,
+2 | a {b: oklab(list.slash(1%, 2, 3))}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+  input.scss 2:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/slash/one/input.scss
+@use 'sass:list';
+$single-arg-slash-separated: list.append((), 1% 2 3, $separator: slash);
+a {b: oklab($single-arg-slash-separated)}
+
+<===> list/slash/one/error
+Error: $channels: Only 2 slash-separated elements allowed, but 1 was passed.
+  ,
+3 | a {b: oklab($single-arg-slash-separated)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+  input.scss 3:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/empty/input.scss
+a {b: oklab(())}
+
+<===> list/empty/error
+Error: $channels: Color component list may not be empty.
+  ,
+1 | a {b: oklab(())}
+  |       ^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/empty_space/input.scss
+@use 'sass:list';
+$empty-space: list.join((), (), $separator: space);
+a {b: oklab(())}
+
+<===> list/empty_space/error
+Error: $channels: Color component list may not be empty.
+  ,
+3 | a {b: oklab(())}
+  |       ^^^^^^^^^
+  '
+  input.scss 3:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/too_few_channels/input.scss
+a {b: oklab(1% 2)}
+
+<===> list/too_few_channels/error
+Error: $channels: The oklab color space has 3 channels but (1% 2) has 2.
+  ,
+1 | a {b: oklab(1% 2)}
+  |       ^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> list/too_many_channels/input.scss
+a {b: oklab(1% 2 3 0.4)}
+
+<===> list/too_many_channels/error
+Error: $channels: The oklab color space has 3 channels but (1% 2 3 0.4) has 4.
+  ,
+1 | a {b: oklab(1% 2 3 0.4)}
+  |       ^^^^^^^^^^^^^^^^^
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> too_few_args/input.scss
+a {b: oklab()}
+
+<===> too_few_args/error
+Error: Missing argument $channels.
+  ,--> input.scss
+1 | a {b: oklab()}
+  |       ^^^^^^^ invocation
+  '
+  ,--> sass:color
+1 | @function oklab($channels) {
+  |           ================ declaration
+  '
+  input.scss 1:7  root stylesheet
+
+<===>
+================================================================================
+<===> too_many_args/input.scss
+a {b: oklab(1%, 2, 3, 0.4)}
+
+<===> too_many_args/error
+Error: Only 1 argument allowed, but 4 were passed.
+  ,--> input.scss
+1 | a {b: oklab(1%, 2, 3, 0.4)}
+  |       ^^^^^^^^^^^^^^^^^^^^ invocation
+  '
+  ,--> sass:color
+1 | @function oklab($channels) {
+  |           ================ declaration
+  '
+  input.scss 1:7  root stylesheet
diff --git a/spec/core_functions/color/oklab/no_alpha.hrx b/spec/core_functions/color/oklab/no_alpha.hrx
new file mode 100644
index 0000000000..89c41fc681
--- /dev/null
+++ b/spec/core_functions/color/oklab/no_alpha.hrx
@@ -0,0 +1,189 @@
+<===> unitless/ab/in_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 -3));
+
+<===> unitless/ab/in_range/output.css
+a {
+  value: oklab(1% 2 -3);
+  channels: 1% 2 -3 / 1;
+}
+
+<===>
+================================================================================
+<===> unitless/ab/above_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 126 300));
+
+<===> unitless/ab/above_range/output.css
+a {
+  value: oklab(1% 126 300);
+  channels: 1% 126 300 / 1;
+}
+
+<===>
+================================================================================
+<===> unitless/ab/below_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% -126 -300));
+
+<===> unitless/ab/below_range/output.css
+a {
+  value: oklab(1% -126 -300);
+  channels: 1% -126 -300 / 1;
+}
+
+<===>
+================================================================================
+<===> unitless/lightness/in_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(0.1 2 -3));
+
+<===> unitless/lightness/in_range/output.css
+a {
+  value: oklab(10% 2 -3);
+  channels: 10% 2 -3 / 1;
+}
+
+<===>
+================================================================================
+<===> unitless/lightness/above_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1.1 2 3));
+
+<===> unitless/lightness/above_range/output.css
+a {
+  value: oklab(100% 2 3);
+  channels: 100% 2 3 / 1;
+}
+
+<===>
+================================================================================
+<===> unitless/lightness/below_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(-0.1 2 3));
+
+<===> unitless/lightness/below_range/output.css
+a {
+  value: oklab(0% 2 3);
+  channels: 0% 2 3 / 1;
+}
+
+<===>
+================================================================================
+<===> percent/ab/in_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2% -3%));
+
+<===> percent/ab/in_range/output.css
+a {
+  value: oklab(1% 0.008 -0.012);
+  channels: 1% 0.008 -0.012 / 1;
+}
+
+<===>
+================================================================================
+<===> percent/ab/above_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 101% 150%));
+
+<===> percent/ab/above_range/output.css
+a {
+  value: oklab(1% 0.404 0.6);
+  channels: 1% 0.404 0.6 / 1;
+}
+
+<===>
+================================================================================
+<===> percent/ab/below_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% -101% -150%));
+
+<===> percent/ab/below_range/output.css
+a {
+  value: oklab(1% -0.404 -0.6);
+  channels: 1% -0.404 -0.6 / 1;
+}
+
+<===>
+================================================================================
+<===> percent/lightness/in_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2% -3%));
+
+<===> percent/lightness/in_range/output.css
+a {
+  value: oklab(1% 0.008 -0.012);
+  channels: 1% 0.008 -0.012 / 1;
+}
+
+<===>
+================================================================================
+<===> percent/lightness/above_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(110% 2 3));
+
+<===> percent/lightness/above_range/output.css
+a {
+  value: oklab(100% 2 3);
+  channels: 100% 2 3 / 1;
+}
+
+<===>
+================================================================================
+<===> percent/lightness/below_range/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(-1% 2 3));
+
+<===> percent/lightness/below_range/output.css
+a {
+  value: oklab(0% 2 3);
+  channels: 0% 2 3 / 1;
+}
+
+<===>
+================================================================================
+<===> none/lightness/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(none 2 3));
+
+<===> none/lightness/output.css
+a {
+  value: oklab(none 2 3);
+  channels: none 2 3 / 1;
+}
+
+<===>
+================================================================================
+<===> none/a/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% none 3));
+
+<===> none/a/output.css
+a {
+  value: oklab(1% none 3);
+  channels: 1% none 3 / 1;
+}
+
+<===>
+================================================================================
+<===> none/b/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 none));
+
+<===> none/b/output.css
+a {
+  value: oklab(1% 2 none);
+  channels: 1% 2 none / 1;
+}
+
+<===>
+================================================================================
+<===> named/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab($channels: 1% 2 3));
+
+<===> named/output.css
+a {
+  value: oklab(1% 2 3);
+  channels: 1% 2 3 / 1;
+}
diff --git a/spec/core_functions/color/oklab/options.yml b/spec/core_functions/color/oklab/options.yml
new file mode 100644
index 0000000000..99ecec7ed1
--- /dev/null
+++ b/spec/core_functions/color/oklab/options.yml
@@ -0,0 +1,3 @@
+---
+:ignore_for:
+- libsass
diff --git a/spec/core_functions/color/oklab/special_functions.hrx b/spec/core_functions/color/oklab/special_functions.hrx
new file mode 100644
index 0000000000..089f5057ff
--- /dev/null
+++ b/spec/core_functions/color/oklab/special_functions.hrx
@@ -0,0 +1,142 @@
+<===> calculation/arg_1/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(calc(1px + 1%) 2 3));
+
+<===> calculation/arg_1/output.css
+a {
+  value: oklab(calc(1px + 1%) 2 3);
+  type: string;
+}
+
+<===>
+================================================================================
+<===> calculation/arg_2/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% calc(1px + 1%) 3));
+
+<===> calculation/arg_2/output.css
+a {
+  value: oklab(1% calc(1px + 1%) 3);
+  type: string;
+}
+
+<===>
+================================================================================
+<===> calculation/arg_3/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 calc(1px + 1%)));
+
+<===> calculation/arg_3/output.css
+a {
+  value: oklab(1% 2 calc(1px + 1%));
+  type: string;
+}
+
+<===>
+================================================================================
+<===> calculation/arg_4/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 3 / calc(1px + 1%)));
+
+<===> calculation/arg_4/output.css
+a {
+  value: oklab(1% 2 3/calc(1px + 1%));
+  type: string;
+}
+
+<===>
+================================================================================
+<===> var/arg_1/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(var(--foo) 2 3));
+
+<===> var/arg_1/output.css
+a {
+  value: oklab(var(--foo) 2 3);
+  type: string;
+}
+
+<===>
+================================================================================
+<===> var/arg_2/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% var(--foo) 3));
+
+<===> var/arg_2/output.css
+a {
+  value: oklab(1% var(--foo) 3);
+  type: string;
+}
+
+<===>
+================================================================================
+<===> var/arg_3/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 var(--foo)));
+
+<===> var/arg_3/output.css
+a {
+  value: oklab(1% 2 var(--foo));
+  type: string;
+}
+
+<===>
+================================================================================
+<===> var/arg_4/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% 2 3 / var(--foo)));
+
+<===> var/arg_4/output.css
+a {
+  value: oklab(1% 2 3/var(--foo));
+  type: string;
+}
+
+<===>
+================================================================================
+<===> multi_argument_var/1_of_2/input.scss
+// var() is substituted before parsing, so it may contain multiple arguments.
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(var(--foo) 2));
+
+<===> multi_argument_var/1_of_2/output.css
+a {
+  value: oklab(var(--foo) 2);
+  type: string;
+}
+
+<===>
+================================================================================
+<===> multi_argument_var/2_of_2/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(1% var(--foo)));
+
+<===> multi_argument_var/2_of_2/output.css
+a {
+  value: oklab(1% var(--foo));
+  type: string;
+}
+
+<===>
+================================================================================
+<===> multi_argument_var/1_of_1/no_alpha/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(var(--foo)));
+
+<===> multi_argument_var/1_of_1/no_alpha/output.css
+a {
+  value: oklab(var(--foo));
+  type: string;
+}
+
+<===>
+================================================================================
+<===> multi_argument_var/1_of_1/alpha/input.scss
+@use 'core_functions/color/oklab/utils';
+@include utils.inspect(oklab(var(--foo) / 0.4));
+
+<===> multi_argument_var/1_of_1/alpha/output.css
+a {
+  value: oklab(var(--foo)/0.4);
+  type: string;
+}
diff --git a/spec/core_functions/color/rgb/error/one_arg.hrx b/spec/core_functions/color/rgb/error/one_arg.hrx
index b16f12e29e..59b4b91a47 100644
--- a/spec/core_functions/color/rgb/error/one_arg.hrx
+++ b/spec/core_functions/color/rgb/error/one_arg.hrx
@@ -101,7 +101,7 @@ a {
 }
 
 <===> type/red/error
-Error: $channels: Expected red "foo" to be a number.
+Error: $channels: Expected red channel to be a number, was "foo".
   ,
 2 |   b: rgb("foo" 2 3);
   |      ^^^^^^^^^^^^^^
@@ -116,7 +116,7 @@ a {
 }
 
 <===> type/green/error
-Error: $channels: Expected green "foo" to be a number.
+Error: $channels: Expected green channel to be a number, was "foo".
   ,
 2 |   b: rgb(1 "foo" 3);
   |      ^^^^^^^^^^^^^^
@@ -131,7 +131,7 @@ a {
 }
 
 <===> type/blue/error
-Error: $channels: Expected blue "foo" to be a number.
+Error: $channels: Expected blue channel to be a number, was "foo".
   ,
 2 |   b: rgb(1 2 "foo");
   |      ^^^^^^^^^^^^^^
@@ -146,7 +146,7 @@ a {
 }
 
 <===> quoted_var_slash/error
-Error: $channels: Expected blue "var(--foo) / 0.4" to be a number.
+Error: $channels: Expected blue channel to be a number, was "var(--foo) / 0.4".
   ,
 2 |   b: rgb(1 2 "var(--foo) / 0.4");
   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^