1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
//! Code for applying replacement templates for matches that have previously been found.
use crate::matching::Var;
use crate::{resolving::ResolvedRule, Match, SsrMatches};
use rustc_hash::{FxHashMap, FxHashSet};
use syntax::ast::{self, AstToken};
use syntax::{SyntaxElement, SyntaxKind, SyntaxNode, SyntaxToken, TextRange, TextSize};
use text_edit::TextEdit;
/// Returns a text edit that will replace each match in `matches` with its corresponding replacement
/// template. Placeholders in the template will have been substituted with whatever they matched to
/// in the original code.
pub(crate) fn matches_to_edit(
matches: &SsrMatches,
file_src: &str,
rules: &[ResolvedRule],
) -> TextEdit {
matches_to_edit_at_offset(matches, file_src, 0.into(), rules)
}
fn matches_to_edit_at_offset(
matches: &SsrMatches,
file_src: &str,
relative_start: TextSize,
rules: &[ResolvedRule],
) -> TextEdit {
let mut edit_builder = TextEdit::builder();
for m in &matches.matches {
edit_builder.replace(
m.range.range.checked_sub(relative_start).unwrap(),
render_replace(m, file_src, rules),
);
}
edit_builder.finish()
}
struct ReplacementRenderer<'a> {
match_info: &'a Match,
file_src: &'a str,
rules: &'a [ResolvedRule],
rule: &'a ResolvedRule,
out: String,
// Map from a range within `out` to a token in `template` that represents a placeholder. This is
// used to validate that the generated source code doesn't split any placeholder expansions (see
// below).
placeholder_tokens_by_range: FxHashMap<TextRange, SyntaxToken>,
// Which placeholder tokens need to be wrapped in parenthesis in order to ensure that when `out`
// is parsed, placeholders don't get split. e.g. if a template of `$a.to_string()` results in `1
// + 2.to_string()` then the placeholder value `1 + 2` was split and needs parenthesis.
placeholder_tokens_requiring_parenthesis: FxHashSet<SyntaxToken>,
}
fn render_replace(match_info: &Match, file_src: &str, rules: &[ResolvedRule]) -> String {
let rule = &rules[match_info.rule_index];
let template = rule
.template
.as_ref()
.expect("You called MatchFinder::edits after calling MatchFinder::add_search_pattern");
let mut renderer = ReplacementRenderer {
match_info,
file_src,
rules,
rule,
out: String::new(),
placeholder_tokens_requiring_parenthesis: FxHashSet::default(),
placeholder_tokens_by_range: FxHashMap::default(),
};
renderer.render_node(&template.node);
renderer.maybe_rerender_with_extra_parenthesis(&template.node);
for comment in &match_info.ignored_comments {
renderer.out.push_str(&comment.syntax().to_string());
}
renderer.out
}
impl ReplacementRenderer<'_> {
fn render_node_children(&mut self, node: &SyntaxNode) {
for node_or_token in node.children_with_tokens() {
self.render_node_or_token(&node_or_token);
}
}
fn render_node_or_token(&mut self, node_or_token: &SyntaxElement) {
match node_or_token {
SyntaxElement::Token(token) => {
self.render_token(&token);
}
SyntaxElement::Node(child_node) => {
self.render_node(&child_node);
}
}
}
fn render_node(&mut self, node: &SyntaxNode) {
use syntax::ast::AstNode;
if let Some(mod_path) = self.match_info.rendered_template_paths.get(&node) {
self.out.push_str(&mod_path.to_string());
// Emit everything except for the segment's name-ref, since we already effectively
// emitted that as part of `mod_path`.
if let Some(path) = ast::Path::cast(node.clone()) {
if let Some(segment) = path.segment() {
for node_or_token in segment.syntax().children_with_tokens() {
if node_or_token.kind() != SyntaxKind::NAME_REF {
self.render_node_or_token(&node_or_token);
}
}
}
}
} else {
self.render_node_children(&node);
}
}
fn render_token(&mut self, token: &SyntaxToken) {
if let Some(placeholder) = self.rule.get_placeholder(&token) {
if let Some(placeholder_value) =
self.match_info.placeholder_values.get(&Var(placeholder.ident.to_string()))
{
let range = &placeholder_value.range.range;
let mut matched_text =
self.file_src[usize::from(range.start())..usize::from(range.end())].to_owned();
let edit = matches_to_edit_at_offset(
&placeholder_value.inner_matches,
self.file_src,
range.start(),
self.rules,
);
let needs_parenthesis =
self.placeholder_tokens_requiring_parenthesis.contains(token);
edit.apply(&mut matched_text);
if needs_parenthesis {
self.out.push('(');
}
self.placeholder_tokens_by_range.insert(
TextRange::new(
TextSize::of(&self.out),
TextSize::of(&self.out) + TextSize::of(&matched_text),
),
token.clone(),
);
self.out.push_str(&matched_text);
if needs_parenthesis {
self.out.push(')');
}
} else {
// We validated that all placeholder references were valid before we
// started, so this shouldn't happen.
panic!(
"Internal error: replacement referenced unknown placeholder {}",
placeholder.ident
);
}
} else {
self.out.push_str(token.text().as_str());
}
}
// Checks if the resulting code, when parsed doesn't split any placeholders due to different
// order of operations between the search pattern and the replacement template. If any do, then
// we rerender the template and wrap the problematic placeholders with parenthesis.
fn maybe_rerender_with_extra_parenthesis(&mut self, template: &SyntaxNode) {
if let Some(node) = parse_as_kind(&self.out, template.kind()) {
self.remove_node_ranges(node);
if self.placeholder_tokens_by_range.is_empty() {
return;
}
self.placeholder_tokens_requiring_parenthesis =
self.placeholder_tokens_by_range.values().cloned().collect();
self.out.clear();
self.render_node(template);
}
}
fn remove_node_ranges(&mut self, node: SyntaxNode) {
self.placeholder_tokens_by_range.remove(&node.text_range());
for child in node.children() {
self.remove_node_ranges(child);
}
}
}
fn parse_as_kind(code: &str, kind: SyntaxKind) -> Option<SyntaxNode> {
use syntax::ast::AstNode;
if ast::Expr::can_cast(kind) {
if let Ok(expr) = ast::Expr::parse(code) {
return Some(expr.syntax().clone());
}
} else if ast::Item::can_cast(kind) {
if let Ok(item) = ast::Item::parse(code) {
return Some(item.syntax().clone());
}
}
None
}
|
