Box shadow compat

Author: devongovett

src/lib.rs

@@ -7620,6 +7620,102 @@ mod tests {
         ..Browsers::default()
       },
     );
+
+    prefix_test(
+      r#"
+      .foo {
+        box-shadow: 0px 0px 22px red;
+        box-shadow: 0px 0px max(2cqw, 22px) red;
+      }
+    "#,
+      indoc! {r#"
+      .foo {
+        box-shadow: 0 0 22px red;
+        box-shadow: 0 0 max(2cqw, 22px) red;
+      }
+    "#
+      },
+      Browsers {
+        safari: Some(14 << 16),
+        ..Browsers::default()
+      },
+    );
+    prefix_test(
+      r#"
+      .foo {
+        box-shadow: 0px 0px 22px red;
+        box-shadow: 0px 0px max(2cqw, 22px) red;
+      }
+    "#,
+      indoc! {r#"
+      .foo {
+        box-shadow: 0 0 max(2cqw, 22px) red;
+      }
+    "#
+      },
+      Browsers {
+        safari: Some(16 << 16),
+        ..Browsers::default()
+      },
+    );
+
+    prefix_test(
+      r#"
+      .foo {
+        box-shadow: 0px 0px 22px red;
+        box-shadow: 0px 0px 22px lab(40% 56.6 39);
+      }
+    "#,
+      indoc! {r#"
+      .foo {
+        box-shadow: 0 0 22px red;
+        box-shadow: 0 0 22px lab(40% 56.6 39);
+      }
+    "#
+      },
+      Browsers {
+        safari: Some(14 << 16),
+        ..Browsers::default()
+      },
+    );
+    prefix_test(
+      r#"
+      .foo {
+        box-shadow: 0px 0px 22px red;
+        box-shadow: 0px 0px 22px lab(40% 56.6 39);
+      }
+    "#,
+      indoc! {r#"
+      .foo {
+        box-shadow: 0 0 22px lab(40% 56.6 39);
+      }
+    "#
+      },
+      Browsers {
+        safari: Some(16 << 16),
+        ..Browsers::default()
+      },
+    );
+
+    prefix_test(
+      r#"
+      .foo {
+        box-shadow: var(--fallback);
+        box-shadow: 0px 0px 22px lab(40% 56.6 39);
+      }
+    "#,
+      indoc! {r#"
+      .foo {
+        box-shadow: var(--fallback);
+        box-shadow: 0 0 22px lab(40% 56.6 39);
+      }
+    "#
+      },
+      Browsers {
+        safari: Some(16 << 16),
+        ..Browsers::default()
+      },
+    );
   }
 
   #[test]

src/properties/box_shadow.rs

@@ -8,7 +8,7 @@ use crate::prefixes::Feature;
 use crate::printer::Printer;
 use crate::properties::Property;
 use crate::targets::Browsers;
-use crate::traits::{Parse, PropertyHandler, ToCss, Zero};
+use crate::traits::{IsCompatible, Parse, PropertyHandler, ToCss, Zero};
 use crate::values::color::{ColorFallbackKind, CssColor};
 use crate::values::length::Length;
 use crate::vendor_prefix::VendorPrefix;
@@ -124,10 +124,21 @@ impl ToCss for BoxShadow {
   }
 }
 
+impl IsCompatible for BoxShadow {
+  fn is_compatible(&self, browsers: Browsers) -> bool {
+    self.color.is_compatible(browsers)
+      && self.x_offset.is_compatible(browsers)
+      && self.y_offset.is_compatible(browsers)
+      && self.blur.is_compatible(browsers)
+      && self.spread.is_compatible(browsers)
+  }
+}
+
 #[derive(Default)]
 pub(crate) struct BoxShadowHandler {
   targets: Option<Browsers>,
   box_shadows: Option<(SmallVec<[BoxShadow; 1]>, VendorPrefix)>,
+  flushed: bool,
 }
 
 impl BoxShadowHandler {
@@ -148,9 +159,15 @@ impl<'i> PropertyHandler<'i> for BoxShadowHandler {
   ) -> bool {
     match property {
       Property::BoxShadow(box_shadows, prefix) => {
+        if self.box_shadows.is_some()
+          && matches!(context.targets, Some(browsers) if !box_shadows.is_compatible(browsers))
+        {
+          self.flush(dest);
+        }
+
         if let Some((val, prefixes)) = &mut self.box_shadows {
           if val != box_shadows && !prefixes.contains(*prefix) {
-            self.finalize(dest, context);
+            self.flush(dest);
             self.box_shadows = Some((box_shadows.clone(), *prefix));
           } else {
             *val = box_shadows.clone();
@@ -161,11 +178,12 @@ impl<'i> PropertyHandler<'i> for BoxShadowHandler {
         }
       }
       Property::Unparsed(unparsed) if matches!(unparsed.property_id, PropertyId::BoxShadow(_)) => {
-        self.finalize(dest, context);
+        self.flush(dest);
 
         let mut unparsed = unparsed.clone();
         context.add_unparsed_fallbacks(&mut unparsed);
-        dest.push(Property::Unparsed(unparsed))
+        dest.push(Property::Unparsed(unparsed));
+        self.flushed = true;
       }
       _ => return false,
     }
@@ -174,14 +192,21 @@ impl<'i> PropertyHandler<'i> for BoxShadowHandler {
   }
 
   fn finalize(&mut self, dest: &mut DeclarationList, _: &mut PropertyHandlerContext<'i, '_>) {
+    self.flush(dest);
+    self.flushed = false;
+  }
+}
+
+impl BoxShadowHandler {
+  fn flush<'i>(&mut self, dest: &mut DeclarationList) {
     if self.box_shadows.is_none() {
       return;
     }
 
     let box_shadows = std::mem::take(&mut self.box_shadows);
 
     if let Some((box_shadows, prefixes)) = box_shadows {
-      if let Some(targets) = self.targets {
+      if let (Some(targets), false) = (self.targets, self.flushed) {
         let mut prefixes = if prefixes.contains(VendorPrefix::None) {
           Feature::BoxShadow.prefixes_for(targets)
         } else {
@@ -237,5 +262,7 @@ impl<'i> PropertyHandler<'i> for BoxShadowHandler {
         dest.push(Property::BoxShadow(box_shadows, prefixes))
       }
     }
+
+    self.flushed = true;
   }
 }