Bundle deprecation message and version in DeprecationInfo

Because the increase in size of `Binding` seemed to create a performance
regression we'll try to reduce the size by putting the rarely used
deprecation on the heap. In fact, the struct is even smaller than before
now, because `deprecation` was previously a wide pointer.

crates/typst-library/src/foundations/scope.rs

@@ -253,12 +253,8 @@ pub struct Binding {
     span: Span,
     /// The category of the binding.
     category: Option<Category>,
-    /// A deprecation message for the definition.
+    /// The deprecation information if this item is deprecated.
-    deprecation_message: Option<&'static str>,
+    deprecation: Option<Box<DeprecationInfo>>,
-    /// A version in which the deprecated binding is planned to be removed.
-    ///
-    /// This is ignored if `deprecation` is `None`.
-    deprecation_until: Option<&'static str>,
 }
 
 /// The different kinds of slots.
@@ -278,8 +274,7 @@ impl Binding {
             span,
             kind: BindingKind::Normal,
             category: None,
-            deprecation_message: None,
+            deprecation: None,
-            deprecation_until: None,
         }
     }
 
@@ -290,7 +285,9 @@ impl Binding {
 
     /// Marks this binding as deprecated, with the given `message`.
     pub fn deprecated(&mut self, message: &'static str) -> &mut Self {
-        self.deprecation_message = Some(message);
+        self.deprecation
+            .get_or_insert_with(|| Box::new(DeprecationInfo::new()))
+            .deprecated_message(message);
         self
     }
 
@@ -298,7 +295,9 @@ impl Binding {
     ///
     /// This is ignored if [`Binding::deprecated`] isn't also set.
     pub fn deprecated_until(&mut self, version: &'static str) -> &mut Self {
-        self.deprecation_until = Some(version);
+        self.deprecation
+            .get_or_insert_with(|| Box::new(DeprecationInfo::new()))
+            .deprecated_until(version);
         self
     }
 
@@ -313,8 +312,8 @@ impl Binding {
     /// - pass `()` to ignore the message.
     /// - pass `(&mut engine, span)` to emit a warning into the engine.
     pub fn read_checked(&self, sink: impl DeprecationSink) -> &Value {
-        if let Some(message) = self.deprecation_message {
+        if let Some(info) = &self.deprecation {
-            sink.emit(message, self.deprecation_until);
+            sink.emit(info.message, info.until);
         }
         &self.value
     }
@@ -350,13 +349,8 @@ impl Binding {
     }
 
     /// A deprecation message for the value, if any.
-    pub fn deprecation_message(&self) -> Option<&'static str> {
+    pub fn deprecation(&self) -> Option<&DeprecationInfo> {
-        self.deprecation_message
+        self.deprecation.as_deref()
-    }
-
-    /// The version in which a deprecated binding is planned to be removed.
-    pub fn deprecation_until(&self) -> Option<&'static str> {
-        self.deprecation_until
     }
 
     /// The category of the value, if any.
@@ -374,6 +368,51 @@ pub enum Capturer {
     Context,
 }
 
+/// Information about a deprecated binding.
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
+pub struct DeprecationInfo {
+    /// A deprecation message for the definition.
+    message: &'static str,
+    /// A version in which the deprecated binding is planned to be removed.
+    until: Option<&'static str>,
+}
+
+impl DeprecationInfo {
+    /// Creates new deprecation info with a default message to display when
+    /// emitting the deprecation warning.
+    pub fn new() -> Self {
+        Self { message: "item is deprecated", until: None }
+    }
+
+    /// Set the message to display when emitting the deprecation warning.
+    pub fn deprecated_message(&mut self, message: &'static str) -> &mut Self {
+        self.message = message;
+        self
+    }
+
+    /// Set the version in which the binding is planned to be removed.
+    pub fn deprecated_until(&mut self, version: &'static str) -> &mut Self {
+        self.until = Some(version);
+        self
+    }
+
+    /// The message to display when emitting the deprecation warning.
+    pub fn message(&self) -> &'static str {
+        self.message
+    }
+
+    /// The version in which the binding is planned to be removed.
+    pub fn until(&self) -> Option<&'static str> {
+        self.until
+    }
+}
+
+impl Default for DeprecationInfo {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 /// The error message when trying to mutate a variable from the standard
 /// library.
 #[cold]

docs/src/lib.rs

@@ -17,6 +17,7 @@ use serde::Deserialize;
 use serde_yaml as yaml;
 use std::sync::LazyLock;
 use typst::diag::{StrResult, bail};
+use typst::foundations::DeprecationInfo;
 use typst::foundations::{
     AutoValue, Binding, Bytes, CastInfo, Func, Module, NoneValue, ParamInfo, Repr, Scope,
     Smart, Type, Value,
@@ -291,14 +292,8 @@ fn category_page(resolver: &dyn Resolver, category: Category) -> PageModel {
         match binding.read() {
             Value::Func(func) => {
                 let name = func.name().unwrap();
-                let subpage = func_page(
+                let subpage =
-                    resolver,
+                    func_page(resolver, &route, func, path, binding.deprecation());
-                    &route,
-                    func,
-                    path,
-                    binding.deprecation_message(),
-                    binding.deprecation_until(),
-                );
                 items.push(CategoryItem {
                     name: name.into(),
                     route: subpage.route.clone(),
@@ -387,11 +382,9 @@ fn func_page(
     parent: &str,
     func: &Func,
     path: &[&str],
-    deprecation_message: Option<&'static str>,
+    deprecation: Option<&DeprecationInfo>,
-    deprecation_until: Option<&'static str>,
 ) -> PageModel {
-    let model =
+    let model = func_model(resolver, func, path, false, deprecation);
-        func_model(resolver, func, path, false, deprecation_message, deprecation_until);
     let name = func.name().unwrap();
     PageModel {
         route: eco_format!("{parent}{}/", urlify(name)),
@@ -410,8 +403,7 @@ fn func_model(
     func: &Func,
     path: &[&str],
     nested: bool,
-    deprecation_message: Option<&'static str>,
+    deprecation: Option<&DeprecationInfo>,
-    deprecation_until: Option<&'static str>,
 ) -> FuncModel {
     let name = func.name().unwrap();
     let scope = func.scope().unwrap();
@@ -447,8 +439,8 @@ fn func_model(
         oneliner: oneliner(details),
         element: func.element().is_some(),
         contextual: func.contextual().unwrap_or(false),
-        deprecation_message,
+        deprecation_message: deprecation.map(DeprecationInfo::message),
-        deprecation_until,
+        deprecation_until: deprecation.and_then(DeprecationInfo::until),
         details: Html::markdown(resolver, details, nesting),
         example: example.map(|md| Html::markdown(resolver, md, None)),
         self_,
@@ -531,14 +523,7 @@ fn scope_models(resolver: &dyn Resolver, name: &str, scope: &Scope) -> Vec<FuncM
         .iter()
         .filter_map(|(_, binding)| {
             let Value::Func(func) = binding.read() else { return None };
-            Some(func_model(
+            Some(func_model(resolver, func, &[name], true, binding.deprecation()))
-                resolver,
-                func,
-                &[name],
-                true,
-                binding.deprecation_message(),
-                binding.deprecation_until(),
-            ))
         })
         .collect()
 }
@@ -619,14 +604,7 @@ fn group_page(
         let Ok(ref func) = binding.read().clone().cast::<Func>() else {
             panic!("not a function")
         };
-        let func = func_model(
+        let func = func_model(resolver, func, &path, true, binding.deprecation());
-            resolver,
-            func,
-            &path,
-            true,
-            binding.deprecation_message(),
-            binding.deprecation_until(),
-        );
         let id_base = urlify(&eco_format!("functions-{}", func.name));
         let children = func_outline(&func, &id_base);
         outline_items.push(OutlineItem {
@@ -693,7 +671,7 @@ fn type_model(resolver: &dyn Resolver, ty: &Type) -> TypeModel {
         constructor: ty
             .constructor()
             .ok()
-            .map(|func| func_model(resolver, &func, &[], true, None, None)),
+            .map(|func| func_model(resolver, &func, &[], true, None)),
         scope: scope_models(resolver, ty.short_name(), ty.scope()),
     }
 }
@@ -762,8 +740,8 @@ fn symbols_model(resolver: &dyn Resolver, group: &GroupData) -> SymbolsModel {
                     .map(|(other, _, _)| complete(other))
                     .collect(),
                 deprecation_message: deprecation_message
-                    .or_else(|| binding.deprecation_message()),
+                    .or_else(|| binding.deprecation().map(DeprecationInfo::message)),
-                deprecation_until: binding.deprecation_until(),
+                deprecation_until: binding.deprecation().and_then(DeprecationInfo::until),
             });
         }
     }