1 //! Syntax highlighting injections such as highlighting of documentation tests.
3 use std::{collections::BTreeMap, convert::TryFrom};
6 use ide_db::call_info::ActiveParameter;
7 use itertools::Itertools;
8 use syntax::{ast, AstToken, SyntaxNode, SyntaxToken, TextRange, TextSize};
10 use crate::{Analysis, Highlight, HighlightModifier, HighlightTag, HighlightedRange, RootDatabase};
12 use super::HighlightedRangeStack;
14 pub(super) fn highlight_injection(
15 acc: &mut HighlightedRangeStack,
16 sema: &Semantics<RootDatabase>,
18 expanded: SyntaxToken,
20 let active_parameter = ActiveParameter::at_token(&sema, expanded)?;
21 if !active_parameter.name.starts_with("ra_fixture") {
24 let value = literal.value()?;
25 let marker_info = MarkerInfo::new(&*value);
26 let (analysis, tmp_file_id) = Analysis::from_single_file(marker_info.cleaned_text.clone());
28 if let Some(range) = literal.open_quote_text_range() {
29 acc.add(HighlightedRange {
31 highlight: HighlightTag::StringLiteral.into(),
36 for mut h in analysis.highlight(tmp_file_id).unwrap() {
37 let range = marker_info.map_range_up(h.range);
38 if let Some(range) = literal.map_range_up(range) {
44 if let Some(range) = literal.close_quote_text_range() {
45 acc.add(HighlightedRange {
47 highlight: HighlightTag::StringLiteral.into(),
55 /// Data to remove `$0` from string and map ranges
56 #[derive(Default, Debug)]
59 markers: Vec<TextRange>,
63 fn new(mut text: &str) -> Self {
66 let mut res = MarkerInfo::default();
67 let mut offset: TextSize = 0.into();
68 while !text.is_empty() {
69 let idx = text.find(marker).unwrap_or(text.len());
70 let (chunk, next) = text.split_at(idx);
72 res.cleaned_text.push_str(chunk);
73 offset += TextSize::of(chunk);
75 if let Some(next) = text.strip_prefix(marker) {
78 let marker_len = TextSize::of(marker);
79 res.markers.push(TextRange::at(offset, marker_len));
85 fn map_range_up(&self, range: TextRange) -> TextRange {
87 self.map_offset_up(range.start(), true),
88 self.map_offset_up(range.end(), false),
91 fn map_offset_up(&self, mut offset: TextSize, start: bool) -> TextSize {
92 for r in &self.markers {
93 if r.start() < offset || (start && r.start() == offset) {
101 /// Mapping from extracted documentation code to original code
102 type RangesMap = BTreeMap<TextSize, TextSize>;
104 const RUSTDOC_FENCE: &'static str = "```";
105 const RUSTDOC_FENCE_TOKENS: &[&'static str] = &[
117 /// Extracts Rust code from documentation comments as well as a mapping from
118 /// the extracted source code back to the original source ranges.
119 /// Lastly, a vector of new comment highlight ranges (spanning only the
120 /// comment prefix) is returned which is used in the syntax highlighting
121 /// injection to replace the previous (line-spanning) comment ranges.
122 pub(super) fn extract_doc_comments(
124 ) -> Option<(String, RangesMap, Vec<HighlightedRange>)> {
125 // wrap the doctest into function body to get correct syntax highlighting
126 let prefix = "fn doctest() {\n";
128 // Mapping from extracted documentation code to original code
129 let mut range_mapping: RangesMap = BTreeMap::new();
130 let mut line_start = TextSize::try_from(prefix.len()).unwrap();
131 let mut is_codeblock = false;
132 let mut is_doctest = false;
133 // Replace the original, line-spanning comment ranges by new, only comment-prefix
134 // spanning comment ranges.
135 let mut new_comments = Vec::new();
137 .children_with_tokens()
138 .filter_map(|el| el.into_token().and_then(ast::Comment::cast))
139 .filter(|comment| comment.kind().doc.is_some())
141 if let Some(idx) = comment.text().find(RUSTDOC_FENCE) {
142 is_codeblock = !is_codeblock;
143 // Check whether code is rust by inspecting fence guards
144 let guards = &comment.text()[idx + RUSTDOC_FENCE.len()..];
146 guards.split(',').all(|sub| RUSTDOC_FENCE_TOKENS.contains(&sub.trim()));
147 is_doctest = is_codeblock && is_rust;
154 let prefix_len = comment.prefix().len();
155 let line: &str = comment.text().as_str();
156 let range = comment.syntax().text_range();
158 // whitespace after comment is ignored
159 let pos = if let Some(ws) = line.chars().nth(prefix_len).filter(|c| c.is_whitespace()) {
160 prefix_len + ws.len_utf8()
165 // lines marked with `#` should be ignored in output, we skip the `#` char
166 let pos = if let Some(ws) = line.chars().nth(pos).filter(|&c| c == '#') {
172 range_mapping.insert(line_start, range.start() + TextSize::try_from(pos).unwrap());
173 new_comments.push(HighlightedRange {
174 range: TextRange::new(
176 range.start() + TextSize::try_from(pos).unwrap(),
178 highlight: HighlightTag::Comment | HighlightModifier::Documentation,
181 line_start += range.len() - TextSize::try_from(pos).unwrap();
182 line_start += TextSize::try_from('\n'.len_utf8()).unwrap();
184 line[pos..].to_owned()
188 if doctest.is_empty() {
192 let doctest = format!("{}{}{}", prefix, doctest, suffix);
193 Some((doctest, range_mapping, new_comments))
196 /// Injection of syntax highlighting of doctests.
197 pub(super) fn highlight_doc_comment(
199 range_mapping: RangesMap,
200 new_comments: Vec<HighlightedRange>,
201 stack: &mut HighlightedRangeStack,
203 let (analysis, tmp_file_id) = Analysis::from_single_file(text);
206 for mut h in analysis.with_db(|db| super::highlight(db, tmp_file_id, None, true)).unwrap() {
207 // Determine start offset and end offset in case of multi-line ranges
208 let mut start_offset = None;
209 let mut end_offset = None;
210 for (line_start, orig_line_start) in range_mapping.range(..h.range.end()).rev() {
211 // It's possible for orig_line_start - line_start to be negative. Add h.range.start()
212 // here and remove it from the end range after the loop below so that the values are
213 // always non-negative.
214 let offset = h.range.start() + orig_line_start - line_start;
215 if line_start <= &h.range.start() {
216 start_offset.get_or_insert(offset);
219 end_offset.get_or_insert(offset);
222 if let Some(start_offset) = start_offset {
223 h.range = TextRange::new(
225 h.range.end() + end_offset.unwrap_or(start_offset) - h.range.start(),
228 h.highlight |= HighlightModifier::Injected;
233 // Inject the comment prefix highlight ranges
235 for comment in new_comments {
238 stack.pop_and_inject(None);
239 stack.pop_and_inject(Some(Highlight::from(HighlightTag::Dummy) | HighlightModifier::Injected));