src/librustdoc/passes.rs

   1 // Copyright 2012-2014 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 use std::collections::HashSet;
  12 use rustc::util::nodemap::NodeSet;
  13 use std::cmp;
  14 use std::string::String;
  15 use std::usize;
  16 use syntax::ast;
  17 use syntax::ast_util;
  18
  19 use clean;
  20 use clean::Item;
  21 use plugins;
  22 use fold;
  23 use fold::DocFolder;
  24
  25 /// Strip items marked `#[doc(hidden)]`
  26 pub fn strip_hidden(krate: clean::Crate) -> plugins::PluginResult {
  27     let mut stripped = HashSet::new();
  28
  29     // strip all #[doc(hidden)] items
  30     let krate = {
  31         struct Stripper<'a> {
  32             stripped: &'a mut HashSet<ast::NodeId>
  33         };
  34         impl<'a> fold::DocFolder for Stripper<'a> {
  35             fn fold_item(&mut self, i: Item) -> Option<Item> {
  36                 if i.is_hidden_from_doc() {
  37                     debug!("found one in strip_hidden; removing");
  38                     self.stripped.insert(i.def_id.node);
  39
  40                     // use a dedicated hidden item for given item type if any
  41                     match i.inner {
  42                         clean::StructFieldItem(..) => {
  43                             return Some(clean::Item {
  44                                 inner: clean::StructFieldItem(clean::HiddenStructField),
  45                                 ..i
  46                             });
  47                         }
  48                         _ => {
  49                             return None;
  50                         }
  51                     }
  52                 }
  53
  54                 self.fold_item_recur(i)
  55             }
  56         }
  57         let mut stripper = Stripper{ stripped: &mut stripped };
  58         stripper.fold_crate(krate)
  59     };
  60
  61     // strip any traits implemented on stripped items
  62     let krate = {
  63         struct ImplStripper<'a> {
  64             stripped: &'a mut HashSet<ast::NodeId>
  65         };
  66         impl<'a> fold::DocFolder for ImplStripper<'a> {
  67             fn fold_item(&mut self, i: Item) -> Option<Item> {
  68                 if let clean::ImplItem(clean::Impl{
  69                            for_: clean::ResolvedPath{ did, .. },
  70                            ref trait_, ..
  71                 }) = i.inner {
  72                     // Impls for stripped types don't need to exist
  73                     if self.stripped.contains(&did.node) {
  74                         return None;
  75                     }
  76                     // Impls of stripped traits also don't need to exist
  77                     if let Some(clean::ResolvedPath { did, .. }) = *trait_ {
  78                         if self.stripped.contains(&did.node) {
  79                             return None;
  80                         }
  81                     }
  82                 }
  83                 self.fold_item_recur(i)
  84             }
  85         }
  86         let mut stripper = ImplStripper{ stripped: &mut stripped };
  87         stripper.fold_crate(krate)
  88     };
  89
  90     (krate, None)
  91 }
  92
  93 /// Strip private items from the point of view of a crate or externally from a
  94 /// crate, specified by the `xcrate` flag.
  95 pub fn strip_private(mut krate: clean::Crate) -> plugins::PluginResult {
  96     // This stripper collects all *retained* nodes.
  97     let mut retained = HashSet::new();
  98     let analysis = super::ANALYSISKEY.with(|a| a.clone());
  99     let analysis = analysis.borrow();
 100     let analysis = analysis.as_ref().unwrap();
 101     let exported_items = analysis.exported_items.clone();
 102
 103     // strip all private items
 104     {
 105         let mut stripper = Stripper {
 106             retained: &mut retained,
 107             exported_items: &exported_items,
 108         };
 109         krate = stripper.fold_crate(krate);
 110     }
 111
 112     // strip all private implementations of traits
 113     {
 114         let mut stripper = ImplStripper(&retained);
 115         krate = stripper.fold_crate(krate);
 116     }
 117     (krate, None)
 118 }
 119
 120 struct Stripper<'a> {
 121     retained: &'a mut HashSet<ast::NodeId>,
 122     exported_items: &'a NodeSet,
 123 }
 124
 125 impl<'a> fold::DocFolder for Stripper<'a> {
 126     fn fold_item(&mut self, i: Item) -> Option<Item> {
 127         match i.inner {
 128             // These items can all get re-exported
 129             clean::TypedefItem(..) | clean::StaticItem(..) |
 130             clean::StructItem(..) | clean::EnumItem(..) |
 131             clean::TraitItem(..) | clean::FunctionItem(..) |
 132             clean::VariantItem(..) | clean::MethodItem(..) |
 133             clean::ForeignFunctionItem(..) | clean::ForeignStaticItem(..) => {
 134                 if ast_util::is_local(i.def_id) {
 135                     if !self.exported_items.contains(&i.def_id.node) {
 136                         return None;
 137                     }
 138                     // Traits are in exported_items even when they're totally private.
 139                     if i.is_trait() && i.visibility != Some(ast::Public) {
 140                         return None;
 141                     }
 142                 }
 143             }
 144
 145             clean::ConstantItem(..) => {
 146                 if ast_util::is_local(i.def_id) &&
 147                    !self.exported_items.contains(&i.def_id.node) {
 148                     return None;
 149                 }
 150             }
 151
 152             clean::ExternCrateItem(..) | clean::ImportItem(_) => {
 153                 if i.visibility != Some(ast::Public) {
 154                     return None
 155                 }
 156             }
 157
 158             clean::StructFieldItem(..) => {
 159                 if i.visibility != Some(ast::Public) {
 160                     return Some(clean::Item {
 161                         inner: clean::StructFieldItem(clean::HiddenStructField),
 162                         ..i
 163                     })
 164                 }
 165             }
 166
 167             // handled below
 168             clean::ModuleItem(..) => {}
 169
 170             // trait impls for private items should be stripped
 171             clean::ImplItem(clean::Impl{
 172                 for_: clean::ResolvedPath{ did, .. }, ..
 173             }) => {
 174                 if ast_util::is_local(did) &&
 175                    !self.exported_items.contains(&did.node) {
 176                     return None;
 177                 }
 178             }
 179             clean::DefaultImplItem(..) | clean::ImplItem(..) => {}
 180
 181             // tymethods/macros have no control over privacy
 182             clean::MacroItem(..) | clean::TyMethodItem(..) => {}
 183
 184             // Primitives are never stripped
 185             clean::PrimitiveItem(..) => {}
 186
 187             // Associated consts and types are never stripped
 188             clean::AssociatedConstItem(..) |
 189             clean::AssociatedTypeItem(..) => {}
 190         }
 191
 192         let fastreturn = match i.inner {
 193             // nothing left to do for traits (don't want to filter their
 194             // methods out, visibility controlled by the trait)
 195             clean::TraitItem(..) => true,
 196
 197             // implementations of traits are always public.
 198             clean::ImplItem(ref imp) if imp.trait_.is_some() => true,
 199
 200             // Struct variant fields have inherited visibility
 201             clean::VariantItem(clean::Variant {
 202                 kind: clean::StructVariant(..)
 203             }) => true,
 204             _ => false,
 205         };
 206
 207         let i = if fastreturn {
 208             self.retained.insert(i.def_id.node);
 209             return Some(i);
 210         } else {
 211             self.fold_item_recur(i)
 212         };
 213
 214         match i {
 215             Some(i) => {
 216                 match i.inner {
 217                     // emptied modules/impls have no need to exist
 218                     clean::ModuleItem(ref m)
 219                         if m.items.is_empty() &&
 220                            i.doc_value().is_none() => None,
 221                     clean::ImplItem(ref i) if i.items.is_empty() => None,
 222                     _ => {
 223                         self.retained.insert(i.def_id.node);
 224                         Some(i)
 225                     }
 226                 }
 227             }
 228             None => None,
 229         }
 230     }
 231 }
 232
 233 // This stripper discards all private impls of traits
 234 struct ImplStripper<'a>(&'a HashSet<ast::NodeId>);
 235 impl<'a> fold::DocFolder for ImplStripper<'a> {
 236     fn fold_item(&mut self, i: Item) -> Option<Item> {
 237         if let clean::ImplItem(ref imp) = i.inner {
 238             match imp.trait_ {
 239                 Some(clean::ResolvedPath{ did, .. }) => {
 240                     let ImplStripper(s) = *self;
 241                     if ast_util::is_local(did) && !s.contains(&did.node) {
 242                         return None;
 243                     }
 244                 }
 245                 Some(..) | None => {}
 246             }
 247         }
 248         self.fold_item_recur(i)
 249     }
 250 }
 251
 252
 253 pub fn unindent_comments(krate: clean::Crate) -> plugins::PluginResult {
 254     struct CommentCleaner;
 255     impl fold::DocFolder for CommentCleaner {
 256         fn fold_item(&mut self, i: Item) -> Option<Item> {
 257             let mut i = i;
 258             let mut avec: Vec<clean::Attribute> = Vec::new();
 259             for attr in &i.attrs {
 260                 match attr {
 261                     &clean::NameValue(ref x, ref s)
 262                             if "doc" == *x => {
 263                         avec.push(clean::NameValue("doc".to_string(),
 264                                                    unindent(s)))
 265                     }
 266                     x => avec.push(x.clone())
 267                 }
 268             }
 269             i.attrs = avec;
 270             self.fold_item_recur(i)
 271         }
 272     }
 273     let mut cleaner = CommentCleaner;
 274     let krate = cleaner.fold_crate(krate);
 275     (krate, None)
 276 }
 277
 278 pub fn collapse_docs(krate: clean::Crate) -> plugins::PluginResult {
 279     struct Collapser;
 280     impl fold::DocFolder for Collapser {
 281         fn fold_item(&mut self, i: Item) -> Option<Item> {
 282             let mut docstr = String::new();
 283             let mut i = i;
 284             for attr in &i.attrs {
 285                 match *attr {
 286                     clean::NameValue(ref x, ref s)
 287                             if "doc" == *x => {
 288                         docstr.push_str(s);
 289                         docstr.push('\n');
 290                     },
 291                     _ => ()
 292                 }
 293             }
 294             let mut a: Vec<clean::Attribute> = i.attrs.iter().filter(|&a| match a {
 295                 &clean::NameValue(ref x, _) if "doc" == *x => false,
 296                 _ => true
 297             }).cloned().collect();
 298             if !docstr.is_empty() {
 299                 a.push(clean::NameValue("doc".to_string(), docstr));
 300             }
 301             i.attrs = a;
 302             self.fold_item_recur(i)
 303         }
 304     }
 305     let mut collapser = Collapser;
 306     let krate = collapser.fold_crate(krate);
 307     (krate, None)
 308 }
 309
 310 pub fn unindent(s: &str) -> String {
 311     let lines = s.lines_any().collect::<Vec<&str> >();
 312     let mut saw_first_line = false;
 313     let mut saw_second_line = false;
 314     let min_indent = lines.iter().fold(usize::MAX, |min_indent, line| {
 315
 316         // After we see the first non-whitespace line, look at
 317         // the line we have. If it is not whitespace, and therefore
 318         // part of the first paragraph, then ignore the indentation
 319         // level of the first line
 320         let ignore_previous_indents =
 321             saw_first_line &&
 322             !saw_second_line &&
 323             !line.chars().all(|c| c.is_whitespace());
 324
 325         let min_indent = if ignore_previous_indents {
 326             usize::MAX
 327         } else {
 328             min_indent
 329         };
 330
 331         if saw_first_line {
 332             saw_second_line = true;
 333         }
 334
 335         if line.chars().all(|c| c.is_whitespace()) {
 336             min_indent
 337         } else {
 338             saw_first_line = true;
 339             let mut spaces = 0;
 340             line.chars().all(|char| {
 341                 // Only comparing against space because I wouldn't
 342                 // know what to do with mixed whitespace chars
 343                 if char == ' ' {
 344                     spaces += 1;
 345                     true
 346                 } else {
 347                     false
 348                 }
 349             });
 350             cmp::min(min_indent, spaces)
 351         }
 352     });
 353
 354     if !lines.is_empty() {
 355         let mut unindented = vec![ lines[0].trim().to_string() ];
 356         unindented.push_all(&lines.tail().iter().map(|&line| {
 357             if line.chars().all(|c| c.is_whitespace()) {
 358                 line.to_string()
 359             } else {
 360                 assert!(line.len() >= min_indent);
 361                 line[min_indent..].to_string()
 362             }
 363         }).collect::<Vec<_>>());
 364         unindented.connect("\n")
 365     } else {
 366         s.to_string()
 367     }
 368 }
 369
 370 #[cfg(test)]
 371 mod unindent_tests {
 372     use super::unindent;
 373
 374     #[test]
 375     fn should_unindent() {
 376         let s = "    line1\n    line2".to_string();
 377         let r = unindent(&s);
 378         assert_eq!(r, "line1\nline2");
 379     }
 380
 381     #[test]
 382     fn should_unindent_multiple_paragraphs() {
 383         let s = "    line1\n\n    line2".to_string();
 384         let r = unindent(&s);
 385         assert_eq!(r, "line1\n\nline2");
 386     }
 387
 388     #[test]
 389     fn should_leave_multiple_indent_levels() {
 390         // Line 2 is indented another level beyond the
 391         // base indentation and should be preserved
 392         let s = "    line1\n\n        line2".to_string();
 393         let r = unindent(&s);
 394         assert_eq!(r, "line1\n\n    line2");
 395     }
 396
 397     #[test]
 398     fn should_ignore_first_line_indent() {
 399         // The first line of the first paragraph may not be indented as
 400         // far due to the way the doc string was written:
 401         //
 402         // #[doc = "Start way over here
 403         //          and continue here"]
 404         let s = "line1\n    line2".to_string();
 405         let r = unindent(&s);
 406         assert_eq!(r, "line1\nline2");
 407     }
 408
 409     #[test]
 410     fn should_not_ignore_first_line_indent_in_a_single_line_para() {
 411         let s = "line1\n\n    line2".to_string();
 412         let r = unindent(&s);
 413         assert_eq!(r, "line1\n\n    line2");
 414     }
 415 }