Make blackess and whiteness comply with spec.

Changed the `blackness(..)` and `whiteness(..)` functions to return blackness/whiteness of the integer rgb approximations of the color rather than the exact color.
kaj · Jul 3, 2021 · 4a436b3 · 4a436b3
1 parent de26773
commit 4a436b3
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Showing 4 changed files with 11 additions and 13 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -11,7 +11,9 @@ project adheres to
 
 * Changed the `red(..)`, `green(..)`, and `blue(..)` functions to
   always return integers. Issue #114, thanks @Keats.
-
+* Changed the `blackness(..)` and `whiteness(..)` functions to return
+  blackness/whiteness of the integer rgb approximations of the color
+  rather than the exact color.
 
 ## Release 0.22.0 - 2021-06-20
 

diff --git a/src/sass/functions/color/hwb.rs b/src/sass/functions/color/hwb.rs
@@ -11,10 +11,16 @@ use crate::{Error, Scope, ScopeRef};
 pub fn register(f: &mut Scope) {
     def_va!(f, hwb(kwargs), hwb);
     def!(f, blackness(color), |s| {
-        Ok(percentage(get_color(s, "color")?.to_hwba().blackness()))
+        // Blackness of the rgb approximation that can be represented in css.
+        let (r, g, b, _a) = get_color(s, "color")?.to_rgba().to_bytes();
+        let max_c = *[r, g, b].iter().max().unwrap();
+        Ok(percentage(Rational::new((255 - max_c).into(), 255)))
     });
     def!(f, whiteness(color), |s| {
-        Ok(percentage(get_color(s, "color")?.to_hwba().whiteness()))
+        // Whiteness of the rgb approximation that can be represented in css.
+        let (r, g, b, _a) = get_color(s, "color")?.to_rgba().to_bytes();
+        let min_c = *[r, g, b].iter().min().unwrap();
+        Ok(percentage(Rational::new(min_c.into(), 255)))
     });
 }
 

diff --git a/tests/spec/core_functions/color/blackness.rs b/tests/spec/core_functions/color/blackness.rs
@@ -64,7 +64,6 @@ mod error {
     }
 }
 #[test]
-#[ignore] // wrong result
 fn fraction() {
     assert_eq!(
         runner().ok("@use \'sass:color\';\
@@ -89,7 +88,6 @@ mod middle {
     use super::runner;
 
     #[test]
-    #[ignore] // wrong result
     fn half_whiteness() {
         assert_eq!(
             runner().ok("@use \'sass:color\';\
@@ -100,7 +98,6 @@ mod middle {
         );
     }
     #[test]
-    #[ignore] // wrong result
     fn high_whiteness() {
         assert_eq!(
             runner().ok("@use \'sass:color\';\
@@ -111,7 +108,6 @@ mod middle {
         );
     }
     #[test]
-    #[ignore] // wrong result
     fn zero_whiteness() {
         assert_eq!(
             runner().ok("@use \'sass:color\';\
@@ -133,7 +129,6 @@ fn min() {
     );
 }
 #[test]
-#[ignore] // wrong result
 fn named() {
     assert_eq!(
         runner().ok("@use \'sass:color\';\

diff --git a/tests/spec/core_functions/color/whiteness.rs b/tests/spec/core_functions/color/whiteness.rs
@@ -64,7 +64,6 @@ mod error {
     }
 }
 #[test]
-#[ignore] // wrong result
 fn fraction() {
     assert_eq!(
         runner().ok("@use \'sass:color\';\
@@ -89,7 +88,6 @@ mod middle {
     use super::runner;
 
     #[test]
-    #[ignore] // wrong result
     fn half_blackness() {
         assert_eq!(
             runner().ok("@use \'sass:color\';\
@@ -100,7 +98,6 @@ mod middle {
         );
     }
     #[test]
-    #[ignore] // wrong result
     fn high_blackness() {
         assert_eq!(
             runner().ok("@use \'sass:color\';\
@@ -111,7 +108,6 @@ mod middle {
         );
     }
     #[test]
-    #[ignore] // wrong result
     fn zero_blackness() {
         assert_eq!(
             runner().ok("@use \'sass:color\';\
@@ -133,7 +129,6 @@ fn min() {
     );
 }
 #[test]
-#[ignore] // wrong result
 fn named() {
     assert_eq!(
         runner().ok("@use \'sass:color\';\