src/librustdoc/fold.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 use clean::*;
  12
  13 pub enum FoldItem {
  14     Retain(Item),
  15     Strip(Item),
  16     Erase,
  17 }
  18
  19 impl FoldItem {
  20     pub fn fold(self) -> Option<Item> {
  21         match self {
  22             FoldItem::Erase => None,
  23             FoldItem::Retain(i) => Some(i),
  24             FoldItem::Strip(item@ Item { inner: StrippedItem(..), .. } ) => Some(item),
  25             FoldItem::Strip(mut i) => {
  26                 i.inner = StrippedItem(box i.inner);
  27                 Some(i)
  28             }
  29         }
  30     }
  31 }
  32
  33 pub trait DocFolder : Sized {
  34     fn fold_item(&mut self, item: Item) -> Option<Item> {
  35         self.fold_item_recur(item)
  36     }
  37
  38     /// don't override!
  39     fn fold_inner_recur(&mut self, inner: ItemEnum) -> ItemEnum {
  40         match inner {
  41             StrippedItem(..) => unreachable!(),
  42             ModuleItem(i) => {
  43                 ModuleItem(self.fold_mod(i))
  44             },
  45             StructItem(mut i) => {
  46                 let num_fields = i.fields.len();
  47                 i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  48                 i.fields_stripped |= num_fields != i.fields.len() ||
  49                                      i.fields.iter().any(|f| f.is_stripped());
  50                 StructItem(i)
  51             },
  52             EnumItem(mut i) => {
  53                 let num_variants = i.variants.len();
  54                 i.variants = i.variants.into_iter().filter_map(|x| self.fold_item(x)).collect();
  55                 i.variants_stripped |= num_variants != i.variants.len() ||
  56                                        i.variants.iter().any(|f| f.is_stripped());
  57                 EnumItem(i)
  58             },
  59             TraitItem(mut i) => {
  60                 i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect();
  61                 TraitItem(i)
  62             },
  63             ImplItem(mut i) => {
  64                 i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect();
  65                 ImplItem(i)
  66             },
  67             VariantItem(i) => {
  68                 let i2 = i.clone(); // this clone is small
  69                 match i.kind {
  70                     StructVariant(mut j) => {
  71                         let num_fields = j.fields.len();
  72                         j.fields = j.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  73                         j.fields_stripped |= num_fields != j.fields.len() ||
  74                                              j.fields.iter().any(|f| f.is_stripped());
  75                         VariantItem(Variant {kind: StructVariant(j), ..i2})
  76                     },
  77                     _ => VariantItem(i2)
  78                 }
  79             },
  80             x => x
  81         }
  82     }
  83
  84     /// don't override!
  85     fn fold_item_recur(&mut self, item: Item) -> Option<Item> {
  86         let Item { attrs, name, source, visibility, def_id, inner, stability, deprecation } = item;
  87
  88         let inner = match inner {
  89             StrippedItem(box i) => StrippedItem(box self.fold_inner_recur(i)),
  90             _ => self.fold_inner_recur(inner),
  91         };
  92
  93         Some(Item { attrs: attrs, name: name, source: source, inner: inner,
  94                     visibility: visibility, stability: stability, deprecation: deprecation,
  95                     def_id: def_id })
  96     }
  97
  98     fn fold_mod(&mut self, m: Module) -> Module {
  99         Module {
 100             is_crate: m.is_crate,
 101             items: m.items.into_iter().filter_map(|i| self.fold_item(i)).collect()
 102         }
 103     }
 104
 105     fn fold_crate(&mut self, mut c: Crate) -> Crate {
 106         c.module = c.module.and_then(|module| self.fold_item(module));
 107
 108         c.external_traits = c.external_traits.into_iter().map(|(k, mut v)| {
 109             v.items = v.items.into_iter().filter_map(|i| self.fold_item(i)).collect();
 110             (k, v)
 111         }).collect();
 112         c
 113     }
 114 }