1 files changed, 36 insertions, 0 deletions
diff --git a/servo/components/style/queries/values.rs b/servo/components/style/queries/values.rs
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+++ b/servo/components/style/queries/values.rs
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Common feature values between media and container features.
+
+use app_units::Au;
+use euclid::default::Size2D;
+
+/// The orientation media / container feature.
+/// https://drafts.csswg.org/mediaqueries-5/#orientation
+/// https://drafts.csswg.org/css-contain-3/#orientation
+#[derive(Clone, Copy, Debug, FromPrimitive, Parse, ToCss)]
+#[repr(u8)]
+#[allow(missing_docs)]
+pub enum Orientation {
+    Portrait,
+    Landscape,
+}
+
+impl Orientation {
+    /// A helper to evaluate a orientation query given a generic size getter.
+    pub fn eval(size: Size2D<Au>, value: Option<Self>) -> bool {
+        let query_orientation = match value {
+            Some(v) => v,
+            None => return true,
+        };
+
+        // Per spec, square viewports should be 'portrait'
+        let is_landscape = size.width > size.height;
+        match query_orientation {
+            Self::Landscape => is_landscape,
+            Self::Portrait => !is_landscape,
+        }
+    }
+}