1 files changed, 98 insertions, 0 deletions
diff --git a/servo/components/style/macros.rs b/servo/components/style/macros.rs
new file mode 100644
index 0000000000..5f3a1ea463
--- /dev/null
+++ b/servo/components/style/macros.rs
@@ -0,0 +1,98 @@
+/* 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/. */
+
+//! Various macro helpers.
+
+macro_rules! exclusive_value {
+    (($value:ident, $set:expr) => $ident:path) => {
+        if $value.intersects($set) {
+            return Err(());
+        } else {
+            $ident
+        }
+    };
+}
+
+#[cfg(feature = "gecko")]
+macro_rules! impl_gecko_keyword_conversions {
+    ($name:ident, $utype:ty) => {
+        impl From<$utype> for $name {
+            fn from(bits: $utype) -> $name {
+                $name::from_gecko_keyword(bits)
+            }
+        }
+
+        impl From<$name> for $utype {
+            fn from(v: $name) -> $utype {
+                v.to_gecko_keyword()
+            }
+        }
+    };
+}
+
+macro_rules! trivial_to_computed_value {
+    ($name:ty) => {
+        impl $crate::values::computed::ToComputedValue for $name {
+            type ComputedValue = $name;
+
+            fn to_computed_value(&self, _: &$crate::values::computed::Context) -> Self {
+                self.clone()
+            }
+
+            fn from_computed_value(other: &Self) -> Self {
+                other.clone()
+            }
+        }
+    };
+}
+
+/// A macro to parse an identifier, or return an `UnexpectedIdent` error
+/// otherwise.
+///
+/// FIXME(emilio): The fact that `UnexpectedIdent` is a `SelectorParseError`
+/// doesn't make a lot of sense to me.
+macro_rules! try_match_ident_ignore_ascii_case {
+    ($input:expr, $( $match_body:tt )*) => {{
+        let location = $input.current_source_location();
+        let ident = $input.expect_ident_cloned()?;
+        match_ignore_ascii_case! { &ident,
+            $( $match_body )*
+            _ => return Err(location.new_custom_error(
+                ::selectors::parser::SelectorParseErrorKind::UnexpectedIdent(ident.clone())
+            ))
+        }
+    }}
+}
+
+#[cfg(feature = "servo")]
+macro_rules! local_name {
+    ($s:tt) => {
+        $crate::values::GenericAtomIdent(html5ever::local_name!($s))
+    };
+}
+
+#[cfg(feature = "servo")]
+macro_rules! ns {
+    () => {
+        $crate::values::GenericAtomIdent(html5ever::ns!())
+    };
+    ($s:tt) => {
+        $crate::values::GenericAtomIdent(html5ever::ns!($s))
+    };
+}
+
+#[cfg(feature = "gecko")]
+macro_rules! local_name {
+    ($s:tt) => {
+        $crate::values::AtomIdent(atom!($s))
+    };
+}
+
+/// Asserts the size of a type at compile time.
+macro_rules! size_of_test {
+    ($t: ty, $expected_size: expr) => {
+        #[cfg(target_pointer_width = "64")]
+        const_assert_eq!(std::mem::size_of::<$t>(), $expected_size);
+    };
+}