src/librustdoc/fold.rs

   1 use crate::clean::*;
   2
   3 pub struct StripItem(pub Item);
   4
   5 impl StripItem {
   6     pub fn strip(self) -> Option<Item> {
   7         match self.0 {
   8             Item { inner: StrippedItem(..), .. } => Some(self.0),
   9             mut i => {
  10                 i.inner = StrippedItem(box i.inner);
  11                 Some(i)
  12             }
  13         }
  14     }
  15 }
  16
  17 pub trait DocFolder: Sized {
  18     fn fold_item(&mut self, item: Item) -> Option<Item> {
  19         self.fold_item_recur(item)
  20     }
  21
  22     /// don't override!
  23     fn fold_inner_recur(&mut self, inner: ItemEnum) -> ItemEnum {
  24         match inner {
  25             StrippedItem(..) => unreachable!(),
  26             ModuleItem(i) => ModuleItem(self.fold_mod(i)),
  27             StructItem(mut i) => {
  28                 let num_fields = i.fields.len();
  29                 i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  30                 i.fields_stripped |=
  31                     num_fields != i.fields.len() || i.fields.iter().any(|f| f.is_stripped());
  32                 StructItem(i)
  33             }
  34             UnionItem(mut i) => {
  35                 let num_fields = i.fields.len();
  36                 i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  37                 i.fields_stripped |=
  38                     num_fields != i.fields.len() || i.fields.iter().any(|f| f.is_stripped());
  39                 UnionItem(i)
  40             }
  41             EnumItem(mut i) => {
  42                 let num_variants = i.variants.len();
  43                 i.variants = i.variants.into_iter().filter_map(|x| self.fold_item(x)).collect();
  44                 i.variants_stripped |=
  45                     num_variants != i.variants.len() || i.variants.iter().any(|f| f.is_stripped());
  46                 EnumItem(i)
  47             }
  48             TraitItem(mut i) => {
  49                 i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect();
  50                 TraitItem(i)
  51             }
  52             ImplItem(mut i) => {
  53                 i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect();
  54                 ImplItem(i)
  55             }
  56             VariantItem(i) => {
  57                 let i2 = i.clone(); // this clone is small
  58                 match i.kind {
  59                     VariantKind::Struct(mut j) => {
  60                         let num_fields = j.fields.len();
  61                         j.fields = j.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  62                         j.fields_stripped |= num_fields != j.fields.len()
  63                             || j.fields.iter().any(|f| f.is_stripped());
  64                         VariantItem(Variant { kind: VariantKind::Struct(j), ..i2 })
  65                     }
  66                     _ => VariantItem(i2),
  67                 }
  68             }
  69             x => x,
  70         }
  71     }
  72
  73     /// don't override!
  74     fn fold_item_recur(&mut self, item: Item) -> Option<Item> {
  75         let Item { attrs, name, source, visibility, def_id, inner, stability, deprecation } = item;
  76
  77         let inner = match inner {
  78             StrippedItem(box i) => StrippedItem(box self.fold_inner_recur(i)),
  79             _ => self.fold_inner_recur(inner),
  80         };
  81
  82         Some(Item { attrs, name, source, inner, visibility, stability, deprecation, def_id })
  83     }
  84
  85     fn fold_mod(&mut self, m: Module) -> Module {
  86         Module {
  87             is_crate: m.is_crate,
  88             items: m.items.into_iter().filter_map(|i| self.fold_item(i)).collect(),
  89         }
  90     }
  91
  92     fn fold_crate(&mut self, mut c: Crate) -> Crate {
  93         c.module = c.module.take().and_then(|module| self.fold_item(module));
  94
  95         {
  96             let mut guard = c.external_traits.borrow_mut();
  97             let external_traits = std::mem::replace(&mut *guard, Default::default());
  98             *guard = external_traits
  99                 .into_iter()
 100                 .map(|(k, mut v)| {
 101                     v.items = v.items.into_iter().filter_map(|i| self.fold_item(i)).collect();
 102                     (k, v)
 103                 })
 104                 .collect();
 105         }
 106         c
 107     }
 108 }