1 files changed, 142 insertions, 0 deletions
diff --git a/servo/components/style/macros.rs b/servo/components/style/macros.rs
new file mode 100644
index 0000000000..e60be8efc5
--- /dev/null
+++ b/servo/components/style/macros.rs
@@ -0,0 +1,142 @@
+/* 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,
+            $( $match_body )*
+            _ => return Err(location.new_custom_error(
+                ::selectors::parser::SelectorParseErrorKind::UnexpectedIdent(ident.clone())
+            ))
+        }
+    }}
+}
+
+macro_rules! define_keyword_type {
+    ($name:ident, $css:expr) => {
+        #[allow(missing_docs)]
+        #[derive(
+            Animate,
+            Clone,
+            ComputeSquaredDistance,
+            Copy,
+            MallocSizeOf,
+            PartialEq,
+            SpecifiedValueInfo,
+            ToAnimatedValue,
+            ToAnimatedZero,
+            ToComputedValue,
+            ToCss,
+            ToResolvedValue,
+            ToShmem,
+        )]
+        pub struct $name;
+
+        impl fmt::Debug for $name {
+            fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+                f.write_str($css)
+            }
+        }
+
+        impl $crate::parser::Parse for $name {
+            fn parse<'i, 't>(
+                _context: &$crate::parser::ParserContext,
+                input: &mut ::cssparser::Parser<'i, 't>,
+            ) -> Result<$name, ::style_traits::ParseError<'i>> {
+                input
+                    .expect_ident_matching($css)
+                    .map(|_| $name)
+                    .map_err(|e| e.into())
+            }
+        }
+    };
+}
+
+/// Place a Gecko profiler label on the stack.
+///
+/// The `label_type` argument must be the name of a variant of `ProfilerLabel`.
+#[cfg(feature = "gecko_profiler")]
+#[macro_export]
+macro_rules! profiler_label {
+    ($label_type:ident) => {
+        let mut _profiler_label =
+            ::std::mem::MaybeUninit::<$crate::gecko_bindings::structs::AutoProfilerLabel>::uninit();
+        let _profiler_label = if $crate::gecko::profiler::profiler_is_active() {
+            unsafe {
+                Some($crate::gecko::profiler::AutoProfilerLabel::new(
+                    &mut _profiler_label,
+                    $crate::gecko::profiler::ProfilerLabel::$label_type,
+                ))
+            }
+        } else {
+            None
+        };
+    };
+}
+
+/// No-op when the Gecko profiler is not available.
+#[cfg(not(feature = "gecko_profiler"))]
+#[macro_export]
+macro_rules! profiler_label {
+    ($label_type:ident) => {};
+}
+
+#[cfg(feature = "gecko")]
+macro_rules! local_name {
+    ($s:tt) => {
+        $crate::values::AtomIdent(atom!($s))
+    };
+}