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rollup merge of #17355 : gamazeps/issue17210
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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 use std::iter::Extendable;
13 use std::mem::{replace, swap};
14
15 pub trait DocFolder {
16     fn fold_item(&mut self, item: Item) -> Option<Item> {
17         self.fold_item_recur(item)
18     }
19
20     /// don't override!
21     fn fold_item_recur(&mut self, item: Item) -> Option<Item> {
22         let Item { attrs, name, source, visibility, def_id, inner, stability } = item;
23         let inner = inner;
24         let inner = match inner {
25             StructItem(mut i) => {
26                 let mut foo = Vec::new(); swap(&mut foo, &mut i.fields);
27                 let num_fields = foo.len();
28                 i.fields.extend(foo.into_iter().filter_map(|x| self.fold_item(x)));
29                 i.fields_stripped |= num_fields != i.fields.len();
30                 StructItem(i)
31             },
32             ModuleItem(i) => {
33                 ModuleItem(self.fold_mod(i))
34             },
35             EnumItem(mut i) => {
36                 let mut foo = Vec::new(); swap(&mut foo, &mut i.variants);
37                 let num_variants = foo.len();
38                 i.variants.extend(foo.into_iter().filter_map(|x| self.fold_item(x)));
39                 i.variants_stripped |= num_variants != i.variants.len();
40                 EnumItem(i)
41             },
42             TraitItem(mut i) => {
43                 fn vtrm<T: DocFolder>(this: &mut T, trm: TraitMethod)
44                         -> Option<TraitMethod> {
45                     match trm {
46                         RequiredMethod(it) => {
47                             match this.fold_item(it) {
48                                 Some(x) => return Some(RequiredMethod(x)),
49                                 None => return None,
50                             }
51                         },
52                         ProvidedMethod(it) => {
53                             match this.fold_item(it) {
54                                 Some(x) => return Some(ProvidedMethod(x)),
55                                 None => return None,
56                             }
57                         },
58                         TypeTraitItem(it) => {
59                             match this.fold_item(it) {
60                                 Some(x) => return Some(TypeTraitItem(x)),
61                                 None => return None,
62                             }
63                         }
64                     }
65                 }
66                 let mut foo = Vec::new(); swap(&mut foo, &mut i.items);
67                 i.items.extend(foo.into_iter().filter_map(|x| vtrm(self, x)));
68                 TraitItem(i)
69             },
70             ImplItem(mut i) => {
71                 let mut foo = Vec::new(); swap(&mut foo, &mut i.items);
72                 i.items.extend(foo.into_iter()
73                                   .filter_map(|x| self.fold_item(x)));
74                 ImplItem(i)
75             },
76             VariantItem(i) => {
77                 let i2 = i.clone(); // this clone is small
78                 match i.kind {
79                     StructVariant(mut j) => {
80                         let mut foo = Vec::new(); swap(&mut foo, &mut j.fields);
81                         let num_fields = foo.len();
82                         let c = |x| self.fold_item(x);
83                         j.fields.extend(foo.into_iter().filter_map(c));
84                         j.fields_stripped |= num_fields != j.fields.len();
85                         VariantItem(Variant {kind: StructVariant(j), ..i2})
86                     },
87                     _ => VariantItem(i2)
88                 }
89             },
90             x => x
91         };
92
93         Some(Item { attrs: attrs, name: name, source: source, inner: inner,
94                     visibility: visibility, stability: stability, def_id: 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 = match replace(&mut c.module, None) {
106             Some(module) => self.fold_item(module), None => None
107         };
108         return c;
109     }
110 }