rustdoc: Represent item types as a small number in the search index.

Has negligible improvements with gzip, but saves about 7% without it.
This also has an effect of changing the tie-breaking order of item types.

src/librustdoc/html/format.rs

@@ -1,4 +1,4 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -24,6 +24,8 @@ use syntax::ast;
 use syntax::ast_util;
 
 use clean;
+use html::item_type;
+use html::item_type::ItemType;
 use html::render;
 use html::render::{cache_key, current_location_key};
 
@@ -172,17 +174,17 @@ fn external_path(w: &mut io::Writer, p: &clean::Path, print_all: bool,
         },
         |_cache| {
             Some((Vec::from_slice(fqn), match kind {
-                clean::TypeStruct => "struct",
+                clean::TypeStruct => item_type::Struct,
-                clean::TypeEnum => "enum",
+                clean::TypeEnum => item_type::Enum,
-                clean::TypeFunction => "fn",
+                clean::TypeFunction => item_type::Function,
-                clean::TypeTrait => "trait",
+                clean::TypeTrait => item_type::Trait,
             }))
         })
 }
 
 fn path(w: &mut io::Writer, path: &clean::Path, print_all: bool,
         root: |&render::Cache, &[~str]| -> Option<~str>,
-        info: |&render::Cache| -> Option<(Vec<~str> , &'static str)>)
+        info: |&render::Cache| -> Option<(Vec<~str> , ItemType)>)
     -> fmt::Result
 {
     // The generics will get written to both the title and link
@@ -252,12 +254,12 @@ fn path(w: &mut io::Writer, path: &clean::Path, print_all: bool,
                         url.push_str("/");
                     }
                     match shortty {
-                        "mod" => {
+                        item_type::Module => {
                             url.push_str(*fqp.last().unwrap());
                             url.push_str("/index.html");
                         }
                         _ => {
-                            url.push_str(shortty);
+                            url.push_str(shortty.to_static_str());
                             url.push_str(".");
                             url.push_str(*fqp.last().unwrap());
                             url.push_str(".html");

src/librustdoc/html/item_type.rs

@@ -0,0 +1,97 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Item types.
+
+use std::fmt;
+use clean;
+
+/// Item type. Corresponds to `clean::ItemEnum` variants.
+///
+/// The search index uses item types encoded as smaller numbers which equal to
+/// discriminants. JavaScript then is used to decode them into the original value.
+/// Consequently, every change to this type should be synchronized to
+/// the `itemTypes` mapping table in `static/main.js`.
+#[deriving(Eq, Clone)]
+pub enum ItemType {
+    Module          = 0,
+    Struct          = 1,
+    Enum            = 2,
+    Function        = 3,
+    Typedef         = 4,
+    Static          = 5,
+    Trait           = 6,
+    Impl            = 7,
+    ViewItem        = 8,
+    TyMethod        = 9,
+    Method          = 10,
+    StructField     = 11,
+    Variant         = 12,
+    ForeignFunction = 13,
+    ForeignStatic   = 14,
+    Macro           = 15,
+}
+
+impl ItemType {
+    pub fn to_static_str(&self) -> &'static str {
+        match *self {
+            Module          => "mod",
+            Struct          => "struct",
+            Enum            => "enum",
+            Function        => "fn",
+            Typedef         => "typedef",
+            Static          => "static",
+            Trait           => "trait",
+            Impl            => "impl",
+            ViewItem        => "viewitem",
+            TyMethod        => "tymethod",
+            Method          => "method",
+            StructField     => "structfield",
+            Variant         => "variant",
+            ForeignFunction => "ffi",
+            ForeignStatic   => "ffs",
+            Macro           => "macro",
+        }
+    }
+}
+
+impl fmt::Show for ItemType {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.to_static_str().fmt(f)
+    }
+}
+
+impl fmt::Unsigned for ItemType {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        (*self as uint).fmt(f)
+    }
+}
+
+pub fn shortty(item: &clean::Item) -> ItemType {
+    match item.inner {
+        clean::ModuleItem(..)          => Module,
+        clean::StructItem(..)          => Struct,
+        clean::EnumItem(..)            => Enum,
+        clean::FunctionItem(..)        => Function,
+        clean::TypedefItem(..)         => Typedef,
+        clean::StaticItem(..)          => Static,
+        clean::TraitItem(..)           => Trait,
+        clean::ImplItem(..)            => Impl,
+        clean::ViewItemItem(..)        => ViewItem,
+        clean::TyMethodItem(..)        => TyMethod,
+        clean::MethodItem(..)          => Method,
+        clean::StructFieldItem(..)     => StructField,
+        clean::VariantItem(..)         => Variant,
+        clean::ForeignFunctionItem(..) => ForeignFunction,
+        clean::ForeignStaticItem(..)   => ForeignStatic,
+        clean::MacroItem(..)           => Macro,
+    }
+}
+

src/librustdoc/html/render.rs

@@ -52,6 +52,8 @@ use rustc::util::nodemap::NodeSet;
 use clean;
 use doctree;
 use fold::DocFolder;
+use html::item_type;
+use html::item_type::{ItemType, shortty};
 use html::format::{VisSpace, Method, FnStyleSpace};
 use html::layout;
 use html::markdown;
@@ -138,7 +140,7 @@ pub struct Cache {
     /// URLs when a type is being linked to. External paths are not located in
     /// this map because the `External` type itself has all the information
     /// necessary.
-    pub paths: HashMap<ast::NodeId, (Vec<~str> , &'static str)>,
+    pub paths: HashMap<ast::NodeId, (Vec<~str> , ItemType)>,
 
     /// This map contains information about all known traits of this crate.
     /// Implementations of a crate should inherit the documentation of the
@@ -193,7 +195,7 @@ struct Sidebar<'a> { cx: &'a Context, item: &'a clean::Item, }
 /// Struct representing one entry in the JS search index. These are all emitted
 /// by hand to a large JS file at the end of cache-creation.
 struct IndexItem {
-    ty: &'static str,
+    ty: ItemType,
     name: ~str,
     path: ~str,
     desc: ~str,
@@ -311,7 +313,7 @@ pub fn run(mut krate: clean::Crate, dst: Path) -> io::IoResult<()> {
             if i > 0 {
                 try!(write!(&mut w, ","));
             }
-            try!(write!(&mut w, "\\{ty:\"{}\",name:\"{}\",path:\"{}\",desc:{}",
+            try!(write!(&mut w, "\\{ty:{:u},name:\"{}\",path:\"{}\",desc:{}",
                         item.ty, item.name, item.path,
                         item.desc.to_json().to_str()));
             match item.parent {
@@ -330,7 +332,7 @@ pub fn run(mut krate: clean::Crate, dst: Path) -> io::IoResult<()> {
             if i > 0 {
                 try!(write!(&mut w, ","));
             }
-            try!(write!(&mut w, "\\{type:'{}',name:'{}'\\}",
+            try!(write!(&mut w, "\\{type:{:u},name:'{}'\\}",
                         short, *fqp.last().unwrap()));
         }
         try!(write!(&mut w, "];"));
@@ -622,12 +624,13 @@ impl DocFolder for Cache {
                         } else {
                             let last = self.parent_stack.last().unwrap();
                             let path = match self.paths.find(last) {
-                                Some(&(_, "trait")) =>
+                                Some(&(_, item_type::Trait)) =>
                                     Some(self.stack.slice_to(self.stack.len() - 1)),
                                 // The current stack not necessarily has correlation for
                                 // where the type was defined. On the other hand,
                                 // `paths` always has the right information if present.
-                                Some(&(ref fqp, "struct")) | Some(&(ref fqp, "enum")) =>
+                                Some(&(ref fqp, item_type::Struct)) |
+                                Some(&(ref fqp, item_type::Enum)) =>
                                     Some(fqp.slice_to(fqp.len() - 1)),
                                 Some(..) => Some(self.stack.as_slice()),
                                 None => None
@@ -687,7 +690,7 @@ impl DocFolder for Cache {
             clean::VariantItem(..) => {
                 let mut stack = self.stack.clone();
                 stack.pop();
-                self.paths.insert(item.id, (stack, "enum"));
+                self.paths.insert(item.id, (stack, item_type::Enum));
             }
             _ => {}
         }
@@ -845,7 +848,7 @@ impl Context {
             }
             title.push_str(" - Rust");
             let page = layout::Page {
-                ty: shortty(it),
+                ty: shortty(it).to_static_str(),
                 root_path: cx.root_path.as_slice(),
                 title: title.as_slice(),
             };
@@ -899,27 +902,6 @@ impl Context {
     }
 }
 
-fn shortty(item: &clean::Item) -> &'static str {
-    match item.inner {
-        clean::ModuleItem(..)          => "mod",
-        clean::StructItem(..)          => "struct",
-        clean::EnumItem(..)            => "enum",
-        clean::FunctionItem(..)        => "fn",
-        clean::TypedefItem(..)         => "typedef",
-        clean::StaticItem(..)          => "static",
-        clean::TraitItem(..)           => "trait",
-        clean::ImplItem(..)            => "impl",
-        clean::ViewItemItem(..)        => "viewitem",
-        clean::TyMethodItem(..)        => "tymethod",
-        clean::MethodItem(..)          => "method",
-        clean::StructFieldItem(..)     => "structfield",
-        clean::VariantItem(..)         => "variant",
-        clean::ForeignFunctionItem(..) => "ffi",
-        clean::ForeignStaticItem(..)   => "ffs",
-        clean::MacroItem(..)           => "macro",
-    }
-}
-
 impl<'a> Item<'a> {
     fn ismodule(&self) -> bool {
         match self.item.inner {
@@ -1009,7 +991,7 @@ impl<'a> fmt::Show for Item<'a> {
 fn item_path(item: &clean::Item) -> ~str {
     match item.inner {
         clean::ModuleItem(..) => *item.name.get_ref() + "/index.html",
-        _ => shortty(item) + "." + *item.name.get_ref() + ".html"
+        _ => shortty(item).to_static_str() + "." + *item.name.get_ref() + ".html"
     }
 }
 
@@ -1095,13 +1077,13 @@ fn item_module(w: &mut Writer, cx: &Context,
     indices.sort_by(|&i1, &i2| cmp(&items[i1], &items[i2], i1, i2));
 
     debug!("{:?}", indices);
-    let mut curty = "";
+    let mut curty = None;
     for &idx in indices.iter() {
         let myitem = &items[idx];
 
-        let myty = shortty(myitem);
+        let myty = Some(shortty(myitem));
         if myty != curty {
-            if curty != "" {
+            if curty.is_some() {
                 try!(write!(w, "</table>"));
             }
             curty = myty;
@@ -1704,8 +1686,9 @@ impl<'a> fmt::Show for Sidebar<'a> {
             };
             try!(write!(w, "<div class='block {}'><h2>{}</h2>", short, longty));
             for item in items.iter() {
+                let curty = shortty(cur).to_static_str();
                 let class = if cur.name.get_ref() == item &&
-                               short == shortty(cur) { "current" } else { "" };
+                               short == curty { "current" } else { "" };
                 try!(write!(w, "<a class='{ty} {class}' href='{curty, select,
                                 mod{../}
                                 other{}
@@ -1716,7 +1699,7 @@ impl<'a> fmt::Show for Sidebar<'a> {
                        ty = short,
                        tysel = short,
                        class = class,
-                       curty = shortty(cur),
+                       curty = curty,
                        name = item.as_slice()));
             }
             try!(write!(w, "</div>"));
@@ -1735,7 +1718,7 @@ impl<'a> fmt::Show for Sidebar<'a> {
 fn build_sidebar(m: &clean::Module) -> HashMap<~str, Vec<~str> > {
     let mut map = HashMap::new();
     for item in m.items.iter() {
-        let short = shortty(item);
+        let short = shortty(item).to_static_str();
         let myname = match item.name {
             None => continue,
             Some(ref s) => s.to_owned(),

src/librustdoc/html/static/main.js

@@ -135,7 +135,7 @@
         function execQuery(query, max, searchWords) {
             var valLower = query.query.toLowerCase(),
                 val = valLower,
-                typeFilter = query.type,
+                typeFilter = itemTypeFromName(query.type),
                 results = [],
                 split = valLower.split("::");
 
@@ -156,7 +156,7 @@
                 for (var i = 0; i < nSearchWords; i += 1) {
                     if (searchWords[i] === val) {
                         // filter type: ... queries
-                        if (!typeFilter || typeFilter === searchIndex[i].ty) {
+                        if (typeFilter < 0 || typeFilter === searchIndex[i].ty) {
                             results.push({id: i, index: -1});
                         }
                     }
@@ -174,7 +174,7 @@
                             searchWords[j].replace(/_/g, "").indexOf(val) > -1)
                         {
                             // filter type: ... queries
-                            if (!typeFilter || typeFilter === searchIndex[j].ty) {
+                            if (typeFilter < 0 || typeFilter === searchIndex[j].ty) {
                                 results.push({id: j, index: searchWords[j].replace(/_/g, "").indexOf(val)});
                             }
                         }
@@ -405,7 +405,7 @@
 
                     shown.push(item);
                     name = item.name;
-                    type = item.ty;
+                    type = itemTypes[item.ty];
 
                     output += '<tr class="' + type + ' result"><td>';
 
@@ -427,7 +427,7 @@
                         output += item.path + '::' + myparent.name +
                             '::<a href="' + rootPath +
                             item.path.replace(/::/g, '/') +
-                            '/' + myparent.type +
+                            '/' + itemTypes[myparent.type] +
                             '.' + myparent.name +
                             '.html' + anchor +
                             '" class="' + type +
@@ -505,6 +505,32 @@
             showResults(results);
         }
 
+        // This mapping table should match the discriminants of
+        // `rustdoc::html::item_type::ItemType` type in Rust.
+        var itemTypes = ["mod",
+                         "struct",
+                         "enum",
+                         "fn",
+                         "typedef",
+                         "static",
+                         "trait",
+                         "impl",
+                         "viewitem",
+                         "tymethod",
+                         "method",
+                         "structfield",
+                         "variant",
+                         "ffi",
+                         "ffs",
+                         "macro"];
+
+        function itemTypeFromName(typename) {
+            for (var i = 0; i < itemTypes.length; ++i) {
+                if (itemTypes[i] === typename) return i;
+            }
+            return -1;
+        }
+
         function buildIndex(rawSearchIndex) {
             searchIndex = [];
             var searchWords = [];

src/librustdoc/lib.rs

@@ -41,6 +41,7 @@ pub mod fold;
 pub mod html {
     pub mod highlight;
     pub mod escape;
+    pub mod item_type;
     pub mod format;
     pub mod layout;
     pub mod markdown;