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) => {
  27                 ModuleItem(self.fold_mod(i))
  28             },
  29             StructItem(mut i) => {
  30                 let num_fields = i.fields.len();
  31                 i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  32                 i.fields_stripped |= num_fields != i.fields.len() ||
  33                                      i.fields.iter().any(|f| f.is_stripped());
  34                 StructItem(i)
  35             },
  36             UnionItem(mut i) => {
  37                 let num_fields = i.fields.len();
  38                 i.fields = i.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  39                 i.fields_stripped |= num_fields != i.fields.len() ||
  40                                      i.fields.iter().any(|f| f.is_stripped());
  41                 UnionItem(i)
  42             },
  43             EnumItem(mut i) => {
  44                 let num_variants = i.variants.len();
  45                 i.variants = i.variants.into_iter().filter_map(|x| self.fold_item(x)).collect();
  46                 i.variants_stripped |= num_variants != i.variants.len() ||
  47                                        i.variants.iter().any(|f| f.is_stripped());
  48                 EnumItem(i)
  49             },
  50             TraitItem(mut i) => {
  51                 i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect();
  52                 TraitItem(i)
  53             },
  54             ImplItem(mut i) => {
  55                 i.items = i.items.into_iter().filter_map(|x| self.fold_item(x)).collect();
  56                 ImplItem(i)
  57             },
  58             VariantItem(i) => {
  59                 let i2 = i.clone(); // this clone is small
  60                 match i.kind {
  61                     VariantKind::Struct(mut j) => {
  62                         let num_fields = j.fields.len();
  63                         j.fields = j.fields.into_iter().filter_map(|x| self.fold_item(x)).collect();
  64                         j.fields_stripped |= num_fields != j.fields.len() ||
  65                                              j.fields.iter().any(|f| f.is_stripped());
  66                         VariantItem(Variant {kind: VariantKind::Struct(j), ..i2})
  67                     },
  68                     _ => VariantItem(i2)
  69                 }
  70             },
  71             x => x
  72         }
  73     }
  74
  75     /// don't override!
  76     fn fold_item_recur(&mut self, item: Item) -> Option<Item> {
  77         let Item {
  78             attrs,
  79             name,
  80             source,
  81             visibility,
  82             def_id,
  83             inner,
  84             stability,
  85             deprecation,
  86         } = 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, name, source, inner, visibility,
  94                     stability, deprecation, def_id })
  95     }
  96
  97     fn fold_mod(&mut self, m: Module) -> Module {
  98         Module {
  99             is_crate: m.is_crate,
 100             items: m.items.into_iter().filter_map(|i| self.fold_item(i)).collect()
 101         }
 102     }
 103
 104     fn fold_crate(&mut self, mut c: Crate) -> Crate {
 105         c.module = c.module.take().and_then(|module| self.fold_item(module));
 106
 107         {
 108             let mut guard = c.external_traits.borrow_mut();
 109             let external_traits = std::mem::replace(&mut *guard, Default::default());
 110             *guard = external_traits.into_iter().map(|(k, mut v)| {
 111                 v.items = v.items.into_iter().filter_map(|i| self.fold_item(i)).collect();
 112                 (k, v)
 113             }).collect();
 114         }
 115         c
 116     }
 117 }