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authorAleksey Kladov <[email protected]>2018-08-14 11:33:44 +0100
committerAleksey Kladov <[email protected]>2018-08-14 11:33:44 +0100
commit1141d448d960eedba0a5647d525910de706bf778 (patch)
tree144842663edc382addc6b2cb115717d5bb7eb736 /crates/libsyntax2/src/algo
parent5953a348bd6102a868f303d3f732a6ec7d465833 (diff)
Add derive intention
Diffstat (limited to 'crates/libsyntax2/src/algo')
-rw-r--r--crates/libsyntax2/src/algo/search.rs136
1 files changed, 0 insertions, 136 deletions
diff --git a/crates/libsyntax2/src/algo/search.rs b/crates/libsyntax2/src/algo/search.rs
deleted file mode 100644
index 46404f537..000000000
--- a/crates/libsyntax2/src/algo/search.rs
+++ /dev/null
@@ -1,136 +0,0 @@
1use {Node, NodeType, TextUnit, TextRange};
2use ::visitor::{visitor, process_subtree_bottom_up};
3
4pub fn child_of_type(node: Node, ty: NodeType) -> Option<Node> {
5 node.children().find(|n| n.ty() == ty)
6}
7
8pub fn children_of_type<'f>(node: Node<'f>, ty: NodeType) -> Box<Iterator<Item=Node<'f>> + 'f> {
9 Box::new(node.children().filter(move |n| n.ty() == ty))
10}
11
12pub fn subtree<'f>(node: Node<'f>) -> Box<Iterator<Item=Node<'f>> + 'f> {
13 Box::new(node.children().flat_map(subtree).chain(::std::iter::once(node)))
14}
15
16pub fn descendants_of_type<'f>(node: Node<'f>, ty: NodeType) -> Vec<Node<'f>> {
17 process_subtree_bottom_up(
18 node,
19 visitor(Vec::new())
20 .visit_nodes(&[ty], |node, nodes| nodes.push(node))
21 )
22}
23
24pub fn child_of_type_exn(node: Node, ty: NodeType) -> Node {
25 child_of_type(node, ty).unwrap_or_else(|| {
26 panic!("No child of type {:?} for {:?}\
27 ----\
28 {}\
29 ----", ty, node.ty(), node.text())
30 })
31}
32
33
34pub fn ancestors(node: Node) -> Ancestors {
35 Ancestors(Some(node))
36}
37
38pub struct Ancestors<'f>(Option<Node<'f>>);
39
40impl<'f> Iterator for Ancestors<'f> {
41 type Item = Node<'f>;
42
43 fn next(&mut self) -> Option<Self::Item> {
44 let current = self.0;
45 self.0 = current.and_then(|n| n.parent());
46 current
47 }
48}
49
50pub fn is_leaf(node: Node) -> bool {
51 node.children().next().is_none() && !node.range().is_empty()
52}
53
54
55#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
56pub enum Direction {
57 Left, Right
58}
59
60pub fn sibling(node: Node, dir: Direction) -> Option<Node> {
61 let (parent, idx) = child_position(node)?;
62 let idx = match dir {
63 Direction::Left => idx.checked_sub(1)?,
64 Direction::Right => idx + 1,
65 };
66 parent.children().nth(idx)
67}
68
69pub mod ast {
70 use {Node, AstNode, TextUnit, AstChildren};
71 use visitor::{visitor, process_subtree_bottom_up};
72 use super::{ancestors, find_leaf_at_offset, LeafAtOffset};
73
74 pub fn ancestor<'f, T: AstNode<'f>>(node: Node<'f>) -> Option<T> {
75 ancestors(node)
76 .filter_map(T::wrap)
77 .next()
78 }
79
80 pub fn ancestor_exn<'f, T: AstNode<'f>>(node: Node<'f>) -> T {
81 ancestor(node).unwrap()
82 }
83
84 pub fn children_of_type<'f, N: AstNode<'f>>(node: Node<'f>) -> AstChildren<N> {
85 AstChildren::new(node.children())
86 }
87
88 pub fn descendants_of_type<'f, N: AstNode<'f>>(node: Node<'f>) -> Vec<N> {
89 process_subtree_bottom_up(
90 node,
91 visitor(Vec::new())
92 .visit::<N, _>(|node, acc| acc.push(node))
93 )
94 }
95
96 pub fn node_at_offset<'f, T: AstNode<'f>>(node: Node<'f>, offset: TextUnit) -> Option<T> {
97 match find_leaf_at_offset(node, offset) {
98 LeafAtOffset::None => None,
99 LeafAtOffset::Single(node) => ancestor(node),
100 LeafAtOffset::Between(left, right) => ancestor(left).or_else(|| ancestor(right)),
101 }
102 }
103}
104
105pub mod traversal {
106 use {Node};
107
108 pub fn bottom_up<'f, F: FnMut(Node<'f>)>(node: Node<'f>, mut f: F)
109 {
110 go(node, &mut f);
111
112 fn go<'f, F: FnMut(Node<'f>)>(node: Node<'f>, f: &mut F) {
113 for child in node.children() {
114 go(child, f)
115 }
116 f(node);
117 }
118 }
119}
120
121fn child_position(child: Node) -> Option<(Node, usize)> {
122 child.parent()
123 .map(|parent| {
124 (parent, parent.children().position(|n| n == child).unwrap())
125 })
126}
127
128fn common_ancestor<'f>(n1: Node<'f>, n2: Node<'f>) -> Node<'f> {
129 for p in ancestors(n1) {
130 if ancestors(n2).any(|a| a == p) {
131 return p;
132 }
133 }
134 panic!("Can't find common ancestor of {:?} and {:?}", n1, n2)
135}
136