src/librustdoc/visit_ast.rs

   1 // Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! Rust AST Visitor. Extracts useful information and massages it into a form
  12 //! usable for clean
  13
  14 use std::collections::HashSet;
  15 use std::mem;
  16
  17 use syntax::abi;
  18 use syntax::ast;
  19 use syntax::attr;
  20 use syntax::attr::AttrMetaMethods;
  21 use syntax::codemap::Span;
  22
  23 use rustc::front::map as hir_map;
  24 use rustc::middle::stability;
  25
  26 use rustc_front::hir;
  27
  28 use core;
  29 use doctree::*;
  30
  31 // looks to me like the first two of these are actually
  32 // output parameters, maybe only mutated once; perhaps
  33 // better simply to have the visit method return a tuple
  34 // containing them?
  35
  36 // also, is there some reason that this doesn't use the 'visit'
  37 // framework from syntax?
  38
  39 pub struct RustdocVisitor<'a, 'tcx: 'a> {
  40     pub module: Module,
  41     pub attrs: Vec<ast::Attribute>,
  42     pub cx: &'a core::DocContext<'a, 'tcx>,
  43     pub analysis: Option<&'a core::CrateAnalysis>,
  44     view_item_stack: HashSet<ast::NodeId>,
  45     inlining_from_glob: bool,
  46 }
  47
  48 impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
  49     pub fn new(cx: &'a core::DocContext<'a, 'tcx>,
  50                analysis: Option<&'a core::CrateAnalysis>) -> RustdocVisitor<'a, 'tcx> {
  51         // If the root is reexported, terminate all recursion.
  52         let mut stack = HashSet::new();
  53         stack.insert(ast::CRATE_NODE_ID);
  54         RustdocVisitor {
  55             module: Module::new(None),
  56             attrs: Vec::new(),
  57             cx: cx,
  58             analysis: analysis,
  59             view_item_stack: stack,
  60             inlining_from_glob: false,
  61         }
  62     }
  63
  64     fn stability(&self, id: ast::NodeId) -> Option<attr::Stability> {
  65         self.cx.tcx_opt().and_then(|tcx| {
  66             self.cx.map.opt_local_def_id(id)
  67                        .and_then(|def_id| stability::lookup(tcx, def_id))
  68                        .cloned()
  69         })
  70     }
  71
  72     pub fn visit(&mut self, krate: &hir::Crate) {
  73         self.attrs = krate.attrs.clone();
  74
  75         self.module = self.visit_mod_contents(krate.span,
  76                                               krate.attrs.clone(),
  77                                               hir::Public,
  78                                               ast::CRATE_NODE_ID,
  79                                               &krate.module,
  80                                               None);
  81         // attach the crate's exported macros to the top-level module:
  82         self.module.macros = krate.exported_macros.iter()
  83             .map(|def| self.visit_macro(def)).collect();
  84         self.module.is_crate = true;
  85     }
  86
  87     pub fn visit_variant_data(&mut self, item: &hir::Item,
  88                             name: ast::Name, sd: &hir::VariantData,
  89                             generics: &hir::Generics) -> Struct {
  90         debug!("Visiting struct");
  91         let struct_type = struct_type_from_def(&*sd);
  92         Struct {
  93             id: item.id,
  94             struct_type: struct_type,
  95             name: name,
  96             vis: item.vis,
  97             stab: self.stability(item.id),
  98             attrs: item.attrs.clone(),
  99             generics: generics.clone(),
 100             fields: sd.fields().iter().cloned().collect(),
 101             whence: item.span
 102         }
 103     }
 104
 105     pub fn visit_enum_def(&mut self, it: &hir::Item,
 106                           name: ast::Name, def: &hir::EnumDef,
 107                           params: &hir::Generics) -> Enum {
 108         debug!("Visiting enum");
 109         Enum {
 110             name: name,
 111             variants: def.variants.iter().map(|v| Variant {
 112                 name: v.node.name,
 113                 attrs: v.node.attrs.clone(),
 114                 stab: self.stability(v.node.data.id()),
 115                 def: v.node.data.clone(),
 116                 whence: v.span,
 117             }).collect(),
 118             vis: it.vis,
 119             stab: self.stability(it.id),
 120             generics: params.clone(),
 121             attrs: it.attrs.clone(),
 122             id: it.id,
 123             whence: it.span,
 124         }
 125     }
 126
 127     pub fn visit_fn(&mut self, item: &hir::Item,
 128                     name: ast::Name, fd: &hir::FnDecl,
 129                     unsafety: &hir::Unsafety,
 130                     constness: hir::Constness,
 131                     abi: &abi::Abi,
 132                     gen: &hir::Generics) -> Function {
 133         debug!("Visiting fn");
 134         Function {
 135             id: item.id,
 136             vis: item.vis,
 137             stab: self.stability(item.id),
 138             attrs: item.attrs.clone(),
 139             decl: fd.clone(),
 140             name: name,
 141             whence: item.span,
 142             generics: gen.clone(),
 143             unsafety: *unsafety,
 144             constness: constness,
 145             abi: *abi,
 146         }
 147     }
 148
 149     pub fn visit_mod_contents(&mut self, span: Span, attrs: Vec<ast::Attribute> ,
 150                               vis: hir::Visibility, id: ast::NodeId,
 151                               m: &hir::Mod,
 152                               name: Option<ast::Name>) -> Module {
 153         let mut om = Module::new(name);
 154         om.where_outer = span;
 155         om.where_inner = m.inner;
 156         om.attrs = attrs;
 157         om.vis = vis;
 158         om.stab = self.stability(id);
 159         om.id = id;
 160         for i in &m.item_ids {
 161             let item = self.cx.map.expect_item(i.id);
 162             self.visit_item(item, None, &mut om);
 163         }
 164         om
 165     }
 166
 167     fn visit_view_path(&mut self, path: hir::ViewPath_,
 168                        om: &mut Module,
 169                        id: ast::NodeId,
 170                        please_inline: bool) -> Option<hir::ViewPath_> {
 171         match path {
 172             hir::ViewPathSimple(dst, base) => {
 173                 if self.resolve_id(id, Some(dst), false, om, please_inline) {
 174                     None
 175                 } else {
 176                     Some(hir::ViewPathSimple(dst, base))
 177                 }
 178             }
 179             hir::ViewPathList(p, paths) => {
 180                 let mine = paths.into_iter().filter(|path| {
 181                     !self.resolve_id(path.node.id(), None, false, om,
 182                                      please_inline)
 183                 }).collect::<Vec<hir::PathListItem>>();
 184
 185                 if mine.is_empty() {
 186                     None
 187                 } else {
 188                     Some(hir::ViewPathList(p, mine))
 189                 }
 190             }
 191
 192             // these are feature gated anyway
 193             hir::ViewPathGlob(base) => {
 194                 if self.resolve_id(id, None, true, om, please_inline) {
 195                     None
 196                 } else {
 197                     Some(hir::ViewPathGlob(base))
 198                 }
 199             }
 200         }
 201
 202     }
 203
 204     fn resolve_id(&mut self, id: ast::NodeId, renamed: Option<ast::Name>,
 205                   glob: bool, om: &mut Module, please_inline: bool) -> bool {
 206         let tcx = match self.cx.tcx_opt() {
 207             Some(tcx) => tcx,
 208             None => return false
 209         };
 210         let def = tcx.def_map.borrow()[&id].def_id();
 211         let def_node_id = match tcx.map.as_local_node_id(def) {
 212             Some(n) => n, None => return false
 213         };
 214         let analysis = match self.analysis {
 215             Some(analysis) => analysis, None => return false
 216         };
 217         if !please_inline && analysis.access_levels.is_public(def) {
 218             return false
 219         }
 220         if !self.view_item_stack.insert(def_node_id) { return false }
 221
 222         let ret = match tcx.map.get(def_node_id) {
 223             hir_map::NodeItem(it) => {
 224                 if glob {
 225                     let prev = mem::replace(&mut self.inlining_from_glob, true);
 226                     match it.node {
 227                         hir::ItemMod(ref m) => {
 228                             for i in &m.item_ids {
 229                                 let i = self.cx.map.expect_item(i.id);
 230                                 self.visit_item(i, None, om);
 231                             }
 232                         }
 233                         hir::ItemEnum(..) => {}
 234                         _ => { panic!("glob not mapped to a module or enum"); }
 235                     }
 236                     self.inlining_from_glob = prev;
 237                 } else {
 238                     self.visit_item(it, renamed, om);
 239                 }
 240                 true
 241             }
 242             _ => false,
 243         };
 244         self.view_item_stack.remove(&def_node_id);
 245         return ret;
 246     }
 247
 248     pub fn visit_item(&mut self, item: &hir::Item,
 249                       renamed: Option<ast::Name>, om: &mut Module) {
 250         debug!("Visiting item {:?}", item);
 251         let name = renamed.unwrap_or(item.name);
 252         match item.node {
 253             hir::ItemExternCrate(ref p) => {
 254                 let path = match *p {
 255                     None => None,
 256                     Some(x) => Some(x.to_string()),
 257                 };
 258                 om.extern_crates.push(ExternCrate {
 259                     name: name,
 260                     path: path,
 261                     vis: item.vis,
 262                     attrs: item.attrs.clone(),
 263                     whence: item.span,
 264                 })
 265             }
 266             hir::ItemUse(ref vpath) => {
 267                 let node = vpath.node.clone();
 268                 let node = if item.vis == hir::Public {
 269                     let please_inline = item.attrs.iter().any(|item| {
 270                         match item.meta_item_list() {
 271                             Some(list) => {
 272                                 list.iter().any(|i| &i.name()[..] == "inline")
 273                             }
 274                             None => false,
 275                         }
 276                     });
 277                     match self.visit_view_path(node, om, item.id, please_inline) {
 278                         None => return,
 279                         Some(p) => p
 280                     }
 281                 } else {
 282                     node
 283                 };
 284                 om.imports.push(Import {
 285                     id: item.id,
 286                     vis: item.vis,
 287                     attrs: item.attrs.clone(),
 288                     node: node,
 289                     whence: item.span,
 290                 });
 291             }
 292             hir::ItemMod(ref m) => {
 293                 om.mods.push(self.visit_mod_contents(item.span,
 294                                                      item.attrs.clone(),
 295                                                      item.vis,
 296                                                      item.id,
 297                                                      m,
 298                                                      Some(name)));
 299             },
 300             hir::ItemEnum(ref ed, ref gen) =>
 301                 om.enums.push(self.visit_enum_def(item, name, ed, gen)),
 302             hir::ItemStruct(ref sd, ref gen) =>
 303                 om.structs.push(self.visit_variant_data(item, name, sd, gen)),
 304             hir::ItemFn(ref fd, ref unsafety, constness, ref abi, ref gen, _) =>
 305                 om.fns.push(self.visit_fn(item, name, &**fd, unsafety,
 306                                           constness, abi, gen)),
 307             hir::ItemTy(ref ty, ref gen) => {
 308                 let t = Typedef {
 309                     ty: ty.clone(),
 310                     gen: gen.clone(),
 311                     name: name,
 312                     id: item.id,
 313                     attrs: item.attrs.clone(),
 314                     whence: item.span,
 315                     vis: item.vis,
 316                     stab: self.stability(item.id),
 317                 };
 318                 om.typedefs.push(t);
 319             },
 320             hir::ItemStatic(ref ty, ref mut_, ref exp) => {
 321                 let s = Static {
 322                     type_: ty.clone(),
 323                     mutability: mut_.clone(),
 324                     expr: exp.clone(),
 325                     id: item.id,
 326                     name: name,
 327                     attrs: item.attrs.clone(),
 328                     whence: item.span,
 329                     vis: item.vis,
 330                     stab: self.stability(item.id),
 331                 };
 332                 om.statics.push(s);
 333             },
 334             hir::ItemConst(ref ty, ref exp) => {
 335                 let s = Constant {
 336                     type_: ty.clone(),
 337                     expr: exp.clone(),
 338                     id: item.id,
 339                     name: name,
 340                     attrs: item.attrs.clone(),
 341                     whence: item.span,
 342                     vis: item.vis,
 343                     stab: self.stability(item.id),
 344                 };
 345                 om.constants.push(s);
 346             },
 347             hir::ItemTrait(unsafety, ref gen, ref b, ref items) => {
 348                 let t = Trait {
 349                     unsafety: unsafety,
 350                     name: name,
 351                     items: items.clone(),
 352                     generics: gen.clone(),
 353                     bounds: b.iter().cloned().collect(),
 354                     id: item.id,
 355                     attrs: item.attrs.clone(),
 356                     whence: item.span,
 357                     vis: item.vis,
 358                     stab: self.stability(item.id),
 359                 };
 360                 om.traits.push(t);
 361             },
 362             hir::ItemImpl(unsafety, polarity, ref gen, ref tr, ref ty, ref items) => {
 363                 let i = Impl {
 364                     unsafety: unsafety,
 365                     polarity: polarity,
 366                     generics: gen.clone(),
 367                     trait_: tr.clone(),
 368                     for_: ty.clone(),
 369                     items: items.clone(),
 370                     attrs: item.attrs.clone(),
 371                     id: item.id,
 372                     whence: item.span,
 373                     vis: item.vis,
 374                     stab: self.stability(item.id),
 375                 };
 376                 // Don't duplicate impls when inlining glob imports, we'll pick
 377                 // them up regardless of where they're located.
 378                 if !self.inlining_from_glob {
 379                     om.impls.push(i);
 380                 }
 381             },
 382             hir::ItemDefaultImpl(unsafety, ref trait_ref) => {
 383                 let i = DefaultImpl {
 384                     unsafety: unsafety,
 385                     trait_: trait_ref.clone(),
 386                     id: item.id,
 387                     attrs: item.attrs.clone(),
 388                     whence: item.span,
 389                 };
 390                 // see comment above about ItemImpl
 391                 if !self.inlining_from_glob {
 392                     om.def_traits.push(i);
 393                 }
 394             }
 395             hir::ItemForeignMod(ref fm) => {
 396                 om.foreigns.push(fm.clone());
 397             }
 398         }
 399     }
 400
 401     // convert each exported_macro into a doc item
 402     fn visit_macro(&self, def: &hir::MacroDef) -> Macro {
 403         // Extract the spans of all matchers. They represent the "interface" of the macro.
 404         let matchers = def.body.chunks(4).map(|arm| arm[0].get_span()).collect();
 405
 406         Macro {
 407             id: def.id,
 408             attrs: def.attrs.clone(),
 409             name: def.name,
 410             whence: def.span,
 411             matchers: matchers,
 412             stab: self.stability(def.id),
 413             imported_from: def.imported_from,
 414         }
 415     }
 416 }