pub struct LanguageMode { parser: Parser, } impl LanguageMode { // buffer, grammar, config, grammars, sync_timeout? pub fn new() -> Self { unimplemented!() // make a new root layer // track markers of injections // // track scope_descriptor: a Vec of scopes for item in tree // // fetch grammar for parser based on language string // update root layer } // fn buffer_changed -> call layer.update(range, new_text) on root layer and then all marker layers // call this on transaction.apply() -> buffer_changed(changes) // // fn parse(language, old_tree, ranges) // // fn tree() -> Tree // // // Highlighting // fn highlight_iter() -> iterates over all the scopes // on_tokenize // on_change_highlighting // Commenting // comment_strings_for_pos // is_commented // Indentation // suggested_indent_for_line_at_buffer_row // suggested_indent_for_buffer_row // indent_level_for_line // TODO: Folding // Syntax APIs // get_syntax_node_containing_range -> // ... // get_syntax_node_at_pos // buffer_range_for_scope_at_pos } pub struct LanguageLayer { // mode // grammar // depth // tree: Tree, } impl LanguageLayer { // fn highlight_iter() -> same as Mode but for this layer. Mode composits these // fn buffer_changed // fn update(range) // fn update_injections() } // -- refactored from tree-sitter-highlight to be able to retain state // TODO: add seek() to iter // problem: any time a layer is updated it must update it's injections on the parent (potentially // removing some from use) // can't modify to vec and exist in it at the same time since that would violate borrows // maybe we can do with an arena // maybe just caching on the top layer and nevermind the injections for now? // // Grammar { // layers: Vec> to prevent memory moves when vec is modified // } // injections tracked by marker: // if marker areas match it's fine and update // if not found add new layer // if length 0 then area got removed, clean up the layer // // layer update: // if range.len = 0 then remove the layer // for change in changes { tree.edit(change) } // tree = parser.parse(.., tree, ..) // calculate affected range and update injections // injection update: // look for existing injections // if present, range = (first injection start, last injection end) // // For now cheat and just throw out non-root layers if they exist. This should still improve // parsing in majority of cases. use std::sync::atomic::{AtomicUsize, Ordering}; use std::{iter, mem, ops, str, usize}; use tree_sitter::{ Language, Node, Parser, Point, Query, QueryCaptures, QueryCursor, QueryError, QueryMatch, Range, Tree, }; const CANCELLATION_CHECK_INTERVAL: usize = 100; /// Indicates which highlight should be applied to a region of source code. #[derive(Copy, Clone, Debug, PartialEq, Eq)] pub struct Highlight(pub usize); /// Represents the reason why syntax highlighting failed. #[derive(Debug, PartialEq, Eq)] pub enum Error { Cancelled, InvalidLanguage, Unknown, } /// Represents a single step in rendering a syntax-highlighted document. #[derive(Copy, Clone, Debug)] pub enum HighlightEvent { Source { start: usize, end: usize }, HighlightStart(Highlight), HighlightEnd, } /// Contains the data neeeded to higlight code written in a particular language. /// /// This struct is immutable and can be shared between threads. pub struct HighlightConfiguration { pub language: Language, pub query: Query, combined_injections_query: Option, locals_pattern_index: usize, highlights_pattern_index: usize, highlight_indices: Vec>, non_local_variable_patterns: Vec, injection_content_capture_index: Option, injection_language_capture_index: Option, local_scope_capture_index: Option, local_def_capture_index: Option, local_def_value_capture_index: Option, local_ref_capture_index: Option, } /// Performs syntax highlighting, recognizing a given list of highlight names. /// /// For the best performance `Highlighter` values should be reused between /// syntax highlighting calls. A separate highlighter is needed for each thread that /// is performing highlighting. pub struct Highlighter { parser: Parser, cursors: Vec, } #[derive(Debug)] struct LocalDef<'a> { name: &'a str, value_range: ops::Range, highlight: Option, } #[derive(Debug)] struct LocalScope<'a> { inherits: bool, range: ops::Range, local_defs: Vec>, } struct HighlightIter<'a, F> where F: FnMut(&str) -> Option<&'a HighlightConfiguration> + 'a, { source: &'a [u8], byte_offset: usize, highlighter: &'a mut Highlighter, injection_callback: F, cancellation_flag: Option<&'a AtomicUsize>, layers: Vec>, iter_count: usize, next_event: Option, last_highlight_range: Option<(usize, usize, usize)>, } struct HighlightIterLayer<'a> { _tree: Tree, cursor: QueryCursor, captures: iter::Peekable>, config: &'a HighlightConfiguration, highlight_end_stack: Vec, scope_stack: Vec>, ranges: Vec, depth: usize, } impl Highlighter { pub fn new() -> Self { Highlighter { parser: Parser::new(), cursors: Vec::new(), } } pub fn parser(&mut self) -> &mut Parser { &mut self.parser } /// Iterate over the highlighted regions for a given slice of source code. pub fn highlight<'a>( &'a mut self, config: &'a HighlightConfiguration, source: &'a [u8], cancellation_flag: Option<&'a AtomicUsize>, mut injection_callback: impl FnMut(&str) -> Option<&'a HighlightConfiguration> + 'a, ) -> Result> + 'a, Error> { let layers = HighlightIterLayer::new( source, self, cancellation_flag, &mut injection_callback, config, 0, vec![Range { start_byte: 0, end_byte: usize::MAX, start_point: Point::new(0, 0), end_point: Point::new(usize::MAX, usize::MAX), }], )?; assert_ne!(layers.len(), 0); let mut result = HighlightIter { source, byte_offset: 0, injection_callback, cancellation_flag, highlighter: self, iter_count: 0, layers, next_event: None, last_highlight_range: None, }; result.sort_layers(); Ok(result) } } impl HighlightConfiguration { /// Creates a `HighlightConfiguration` for a given `Language` and set of highlighting /// queries. /// /// # Parameters /// /// * `language` - The Tree-sitter `Language` that should be used for parsing. /// * `highlights_query` - A string containing tree patterns for syntax highlighting. This /// should be non-empty, otherwise no syntax highlights will be added. /// * `injections_query` - A string containing tree patterns for injecting other languages /// into the document. This can be empty if no injections are desired. /// * `locals_query` - A string containing tree patterns for tracking local variable /// definitions and references. This can be empty if local variable tracking is not needed. /// /// Returns a `HighlightConfiguration` that can then be used with the `highlight` method. pub fn new( language: Language, highlights_query: &str, injection_query: &str, locals_query: &str, ) -> Result { // Concatenate the query strings, keeping track of the start offset of each section. let mut query_source = String::new(); query_source.push_str(injection_query); let locals_query_offset = query_source.len(); query_source.push_str(locals_query); let highlights_query_offset = query_source.len(); query_source.push_str(highlights_query); // Construct a single query by concatenating the three query strings, but record the // range of pattern indices that belong to each individual string. let mut query = Query::new(language, &query_source)?; let mut locals_pattern_index = 0; let mut highlights_pattern_index = 0; for i in 0..(query.pattern_count()) { let pattern_offset = query.start_byte_for_pattern(i); if pattern_offset < highlights_query_offset { if pattern_offset < highlights_query_offset { highlights_pattern_index += 1; } if pattern_offset < locals_query_offset { locals_pattern_index += 1; } } } // Construct a separate query just for dealing with the 'combined injections'. // Disable the combined injection patterns in the main query. let mut combined_injections_query = Query::new(language, injection_query)?; let mut has_combined_queries = false; for pattern_index in 0..locals_pattern_index { let settings = query.property_settings(pattern_index); if settings.iter().any(|s| &*s.key == "injection.combined") { has_combined_queries = true; query.disable_pattern(pattern_index); } else { combined_injections_query.disable_pattern(pattern_index); } } let combined_injections_query = if has_combined_queries { Some(combined_injections_query) } else { None }; // Find all of the highlighting patterns that are disabled for nodes that // have been identified as local variables. let non_local_variable_patterns = (0..query.pattern_count()) .map(|i| { query .property_predicates(i) .iter() .any(|(prop, positive)| !*positive && prop.key.as_ref() == "local") }) .collect(); // Store the numeric ids for all of the special captures. let mut injection_content_capture_index = None; let mut injection_language_capture_index = None; let mut local_def_capture_index = None; let mut local_def_value_capture_index = None; let mut local_ref_capture_index = None; let mut local_scope_capture_index = None; for (i, name) in query.capture_names().iter().enumerate() { let i = Some(i as u32); match name.as_str() { "injection.content" => injection_content_capture_index = i, "injection.language" => injection_language_capture_index = i, "local.definition" => local_def_capture_index = i, "local.definition-value" => local_def_value_capture_index = i, "local.reference" => local_ref_capture_index = i, "local.scope" => local_scope_capture_index = i, _ => {} } } let highlight_indices = vec![None; query.capture_names().len()]; Ok(HighlightConfiguration { language, query, combined_injections_query, locals_pattern_index, highlights_pattern_index, highlight_indices, non_local_variable_patterns, injection_content_capture_index, injection_language_capture_index, local_def_capture_index, local_def_value_capture_index, local_ref_capture_index, local_scope_capture_index, }) } /// Get a slice containing all of the highlight names used in the configuration. pub fn names(&self) -> &[String] { self.query.capture_names() } /// Set the list of recognized highlight names. /// /// Tree-sitter syntax-highlighting queries specify highlights in the form of dot-separated /// highlight names like `punctuation.bracket` and `function.method.builtin`. Consumers of /// these queries can choose to recognize highlights with different levels of specificity. /// For example, the string `function.builtin` will match against `function.method.builtin` /// and `function.builtin.constructor`, but will not match `function.method`. /// /// When highlighting, results are returned as `Highlight` values, which contain the index /// of the matched highlight this list of highlight names. pub fn configure(&mut self, recognized_names: &[String]) { let mut capture_parts = Vec::new(); self.highlight_indices.clear(); self.highlight_indices .extend(self.query.capture_names().iter().map(move |capture_name| { capture_parts.clear(); capture_parts.extend(capture_name.split('.')); let mut best_index = None; let mut best_match_len = 0; for (i, recognized_name) in recognized_names.iter().enumerate() { let mut len = 0; let mut matches = true; for part in recognized_name.split('.') { len += 1; if !capture_parts.contains(&part) { matches = false; break; } } if matches && len > best_match_len { best_index = Some(i); best_match_len = len; } } best_index.map(Highlight) })); } } impl<'a> HighlightIterLayer<'a> { /// Create a new 'layer' of highlighting for this document. /// /// In the even that the new layer contains "combined injections" (injections where multiple /// disjoint ranges are parsed as one syntax tree), these will be eagerly processed and /// added to the returned vector. fn new Option<&'a HighlightConfiguration> + 'a>( source: &'a [u8], highlighter: &mut Highlighter, cancellation_flag: Option<&'a AtomicUsize>, injection_callback: &mut F, mut config: &'a HighlightConfiguration, mut depth: usize, mut ranges: Vec, ) -> Result, Error> { let mut result = Vec::with_capacity(1); let mut queue = Vec::new(); loop { if highlighter.parser.set_included_ranges(&ranges).is_ok() { highlighter .parser .set_language(config.language) .map_err(|_| Error::InvalidLanguage)?; unsafe { highlighter.parser.set_cancellation_flag(cancellation_flag) }; let tree = highlighter .parser .parse(source, None) .ok_or(Error::Cancelled)?; unsafe { highlighter.parser.set_cancellation_flag(None) }; let mut cursor = highlighter.cursors.pop().unwrap_or_else(QueryCursor::new); // Process combined injections. if let Some(combined_injections_query) = &config.combined_injections_query { let mut injections_by_pattern_index = vec![(None, Vec::new(), false); combined_injections_query.pattern_count()]; let matches = cursor.matches(combined_injections_query, tree.root_node(), |n: Node| { &source[n.byte_range()] }); for mat in matches { let entry = &mut injections_by_pattern_index[mat.pattern_index]; let (language_name, content_node, include_children) = injection_for_match(config, combined_injections_query, &mat, source); if language_name.is_some() { entry.0 = language_name; } if let Some(content_node) = content_node { entry.1.push(content_node); } entry.2 = include_children; } for (lang_name, content_nodes, includes_children) in injections_by_pattern_index { if let (Some(lang_name), false) = (lang_name, content_nodes.is_empty()) { if let Some(next_config) = (injection_callback)(lang_name) { let ranges = Self::intersect_ranges( &ranges, &content_nodes, includes_children, ); if !ranges.is_empty() { queue.push((next_config, depth + 1, ranges)); } } } } } // The `captures` iterator borrows the `Tree` and the `QueryCursor`, which // prevents them from being moved. But both of these values are really just // pointers, so it's actually ok to move them. let tree_ref = unsafe { mem::transmute::<_, &'static Tree>(&tree) }; let cursor_ref = unsafe { mem::transmute::<_, &'static mut QueryCursor>(&mut cursor) }; let captures = cursor_ref .captures(&config.query, tree_ref.root_node(), move |n: Node| { &source[n.byte_range()] }) .peekable(); result.push(HighlightIterLayer { highlight_end_stack: Vec::new(), scope_stack: vec![LocalScope { inherits: false, range: 0..usize::MAX, local_defs: Vec::new(), }], cursor, depth, _tree: tree, captures, config, ranges, }); } if queue.is_empty() { break; } else { let (next_config, next_depth, next_ranges) = queue.remove(0); config = next_config; depth = next_depth; ranges = next_ranges; } } Ok(result) } // Compute the ranges that should be included when parsing an injection. // This takes into account three things: // * `parent_ranges` - The ranges must all fall within the *current* layer's ranges. // * `nodes` - Every injection takes place within a set of nodes. The injection ranges // are the ranges of those nodes. // * `includes_children` - For some injections, the content nodes' children should be // excluded from the nested document, so that only the content nodes' *own* content // is reparsed. For other injections, the content nodes' entire ranges should be // reparsed, including the ranges of their children. fn intersect_ranges( parent_ranges: &[Range], nodes: &[Node], includes_children: bool, ) -> Vec { let mut cursor = nodes[0].walk(); let mut result = Vec::new(); let mut parent_range_iter = parent_ranges.iter(); let mut parent_range = parent_range_iter .next() .expect("Layers should only be constructed with non-empty ranges vectors"); for node in nodes.iter() { let mut preceding_range = Range { start_byte: 0, start_point: Point::new(0, 0), end_byte: node.start_byte(), end_point: node.start_position(), }; let following_range = Range { start_byte: node.end_byte(), start_point: node.end_position(), end_byte: usize::MAX, end_point: Point::new(usize::MAX, usize::MAX), }; for excluded_range in node .children(&mut cursor) .filter_map(|child| { if includes_children { None } else { Some(child.range()) } }) .chain([following_range].iter().cloned()) { let mut range = Range { start_byte: preceding_range.end_byte, start_point: preceding_range.end_point, end_byte: excluded_range.start_byte, end_point: excluded_range.start_point, }; preceding_range = excluded_range; if range.end_byte < parent_range.start_byte { continue; } while parent_range.start_byte <= range.end_byte { if parent_range.end_byte > range.start_byte { if range.start_byte < parent_range.start_byte { range.start_byte = parent_range.start_byte; range.start_point = parent_range.start_point; } if parent_range.end_byte < range.end_byte { if range.start_byte < parent_range.end_byte { result.push(Range { start_byte: range.start_byte, start_point: range.start_point, end_byte: parent_range.end_byte, end_point: parent_range.end_point, }); } range.start_byte = parent_range.end_byte; range.start_point = parent_range.end_point; } else { if range.start_byte < range.end_byte { result.push(range); } break; } } if let Some(next_range) = parent_range_iter.next() { parent_range = next_range; } else { return result; } } } } result } // First, sort scope boundaries by their byte offset in the document. At a // given position, emit scope endings before scope beginnings. Finally, emit // scope boundaries from deeper layers first. fn sort_key(&mut self) -> Option<(usize, bool, isize)> { let depth = -(self.depth as isize); let next_start = self .captures .peek() .map(|(m, i)| m.captures[*i].node.start_byte()); let next_end = self.highlight_end_stack.last().cloned(); match (next_start, next_end) { (Some(start), Some(end)) => { if start < end { Some((start, true, depth)) } else { Some((end, false, depth)) } } (Some(i), None) => Some((i, true, depth)), (None, Some(j)) => Some((j, false, depth)), _ => None, } } } impl<'a, F> HighlightIter<'a, F> where F: FnMut(&str) -> Option<&'a HighlightConfiguration> + 'a, { fn emit_event( &mut self, offset: usize, event: Option, ) -> Option> { let result; if self.byte_offset < offset { result = Some(Ok(HighlightEvent::Source { start: self.byte_offset, end: offset, })); self.byte_offset = offset; self.next_event = event; } else { result = event.map(Ok); } self.sort_layers(); result } fn sort_layers(&mut self) { while !self.layers.is_empty() { if let Some(sort_key) = self.layers[0].sort_key() { let mut i = 0; while i + 1 < self.layers.len() { if let Some(next_offset) = self.layers[i + 1].sort_key() { if next_offset < sort_key { i += 1; continue; } } break; } if i > 0 { self.layers[0..(i + 1)].rotate_left(1); } break; } else { let layer = self.layers.remove(0); self.highlighter.cursors.push(layer.cursor); } } } fn insert_layer(&mut self, mut layer: HighlightIterLayer<'a>) { if let Some(sort_key) = layer.sort_key() { let mut i = 1; while i < self.layers.len() { if let Some(sort_key_i) = self.layers[i].sort_key() { if sort_key_i > sort_key { self.layers.insert(i, layer); return; } i += 1; } else { self.layers.remove(i); } } self.layers.push(layer); } } } impl<'a, F> Iterator for HighlightIter<'a, F> where F: FnMut(&str) -> Option<&'a HighlightConfiguration> + 'a, { type Item = Result; fn next(&mut self) -> Option { 'main: loop { // If we've already determined the next highlight boundary, just return it. if let Some(e) = self.next_event.take() { return Some(Ok(e)); } // Periodically check for cancellation, returning `Cancelled` error if the // cancellation flag was flipped. if let Some(cancellation_flag) = self.cancellation_flag { self.iter_count += 1; if self.iter_count >= CANCELLATION_CHECK_INTERVAL { self.iter_count = 0; if cancellation_flag.load(Ordering::Relaxed) != 0 { return Some(Err(Error::Cancelled)); } } } // If none of the layers have any more highlight boundaries, terminate. if self.layers.is_empty() { return if self.byte_offset < self.source.len() { let result = Some(Ok(HighlightEvent::Source { start: self.byte_offset, end: self.source.len(), })); self.byte_offset = self.source.len(); result } else { None }; } // Get the next capture from whichever layer has the earliest highlight boundary. let range; let layer = &mut self.layers[0]; if let Some((next_match, capture_index)) = layer.captures.peek() { let next_capture = next_match.captures[*capture_index]; range = next_capture.node.byte_range(); // If any previous highlight ends before this node starts, then before // processing this capture, emit the source code up until the end of the // previous highlight, and an end event for that highlight. if let Some(end_byte) = layer.highlight_end_stack.last().cloned() { if end_byte <= range.start { layer.highlight_end_stack.pop(); return self.emit_event(end_byte, Some(HighlightEvent::HighlightEnd)); } } } // If there are no more captures, then emit any remaining highlight end events. // And if there are none of those, then just advance to the end of the document. else if let Some(end_byte) = layer.highlight_end_stack.last().cloned() { layer.highlight_end_stack.pop(); return self.emit_event(end_byte, Some(HighlightEvent::HighlightEnd)); } else { return self.emit_event(self.source.len(), None); }; let (mut match_, capture_index) = layer.captures.next().unwrap(); let mut capture = match_.captures[capture_index]; // If this capture represents an injection, then process the injection. if match_.pattern_index < layer.config.locals_pattern_index { let (language_name, content_node, include_children) = injection_for_match(&layer.config, &layer.config.query, &match_, &self.source); // Explicitly remove this match so that none of its other captures will remain // in the stream of captures. match_.remove(); // If a language is found with the given name, then add a new language layer // to the highlighted document. if let (Some(language_name), Some(content_node)) = (language_name, content_node) { if let Some(config) = (self.injection_callback)(language_name) { let ranges = HighlightIterLayer::intersect_ranges( &self.layers[0].ranges, &[content_node], include_children, ); if !ranges.is_empty() { match HighlightIterLayer::new( self.source, self.highlighter, self.cancellation_flag, &mut self.injection_callback, config, self.layers[0].depth + 1, ranges, ) { Ok(layers) => { for layer in layers { self.insert_layer(layer); } } Err(e) => return Some(Err(e)), } } } } self.sort_layers(); continue 'main; } // Remove from the local scope stack any local scopes that have already ended. while range.start > layer.scope_stack.last().unwrap().range.end { layer.scope_stack.pop(); } // If this capture is for tracking local variables, then process the // local variable info. let mut reference_highlight = None; let mut definition_highlight = None; while match_.pattern_index < layer.config.highlights_pattern_index { // If the node represents a local scope, push a new local scope onto // the scope stack. if Some(capture.index) == layer.config.local_scope_capture_index { definition_highlight = None; let mut scope = LocalScope { inherits: true, range: range.clone(), local_defs: Vec::new(), }; for prop in layer.config.query.property_settings(match_.pattern_index) { if let "local.scope-inherits" = prop.key.as_ref() { scope.inherits = prop.value.as_ref().map_or(true, |r| r.as_ref() == "true"); } } layer.scope_stack.push(scope); } // If the node represents a definition, add a new definition to the // local scope at the top of the scope stack. else if Some(capture.index) == layer.config.local_def_capture_index { reference_highlight = None; definition_highlight = None; let scope = layer.scope_stack.last_mut().unwrap(); let mut value_range = 0..0; for capture in match_.captures { if Some(capture.index) == layer.config.local_def_value_capture_index { value_range = capture.node.byte_range(); } } if let Ok(name) = str::from_utf8(&self.source[range.clone()]) { scope.local_defs.push(LocalDef { name, value_range, highlight: None, }); definition_highlight = scope.local_defs.last_mut().map(|s| &mut s.highlight); } } // If the node represents a reference, then try to find the corresponding // definition in the scope stack. else if Some(capture.index) == layer.config.local_ref_capture_index { if definition_highlight.is_none() { definition_highlight = None; if let Ok(name) = str::from_utf8(&self.source[range.clone()]) { for scope in layer.scope_stack.iter().rev() { if let Some(highlight) = scope.local_defs.iter().rev().find_map(|def| { if def.name == name && range.start >= def.value_range.end { Some(def.highlight) } else { None } }) { reference_highlight = highlight; break; } if !scope.inherits { break; } } } } } // Continue processing any additional matches for the same node. if let Some((next_match, next_capture_index)) = layer.captures.peek() { let next_capture = next_match.captures[*next_capture_index]; if next_capture.node == capture.node { capture = next_capture; match_ = layer.captures.next().unwrap().0; continue; } } self.sort_layers(); continue 'main; } // Otherwise, this capture must represent a highlight. // If this exact range has already been highlighted by an earlier pattern, or by // a different layer, then skip over this one. if let Some((last_start, last_end, last_depth)) = self.last_highlight_range { if range.start == last_start && range.end == last_end && layer.depth < last_depth { self.sort_layers(); continue 'main; } } // If the current node was found to be a local variable, then skip over any // highlighting patterns that are disabled for local variables. if definition_highlight.is_some() || reference_highlight.is_some() { while layer.config.non_local_variable_patterns[match_.pattern_index] { if let Some((next_match, next_capture_index)) = layer.captures.peek() { let next_capture = next_match.captures[*next_capture_index]; if next_capture.node == capture.node { capture = next_capture; match_ = layer.captures.next().unwrap().0; continue; } } self.sort_layers(); continue 'main; } } // Once a highlighting pattern is found for the current node, skip over // any later highlighting patterns that also match this node. Captures // for a given node are ordered by pattern index, so these subsequent // captures are guaranteed to be for highlighting, not injections or // local variables. while let Some((next_match, next_capture_index)) = layer.captures.peek() { let next_capture = next_match.captures[*next_capture_index]; if next_capture.node == capture.node { layer.captures.next(); } else { break; } } let current_highlight = layer.config.highlight_indices[capture.index as usize]; // If this node represents a local definition, then store the current // highlight value on the local scope entry representing this node. if let Some(definition_highlight) = definition_highlight { *definition_highlight = current_highlight; } // Emit a scope start event and push the node's end position to the stack. if let Some(highlight) = reference_highlight.or(current_highlight) { self.last_highlight_range = Some((range.start, range.end, layer.depth)); layer.highlight_end_stack.push(range.end); return self .emit_event(range.start, Some(HighlightEvent::HighlightStart(highlight))); } self.sort_layers(); } } } fn injection_for_match<'a>( config: &HighlightConfiguration, query: &'a Query, query_match: &QueryMatch<'a>, source: &'a [u8], ) -> (Option<&'a str>, Option>, bool) { let content_capture_index = config.injection_content_capture_index; let language_capture_index = config.injection_language_capture_index; let mut language_name = None; let mut content_node = None; for capture in query_match.captures { let index = Some(capture.index); if index == language_capture_index { language_name = capture.node.utf8_text(source).ok(); } else if index == content_capture_index { content_node = Some(capture.node); } } let mut include_children = false; for prop in query.property_settings(query_match.pattern_index) { match prop.key.as_ref() { // In addition to specifying the language name via the text of a // captured node, it can also be hard-coded via a `#set!` predicate // that sets the injection.language key. "injection.language" => { if language_name.is_none() { language_name = prop.value.as_ref().map(|s| s.as_ref()) } } // By default, injections do not include the *children* of an // `injection.content` node - only the ranges that belong to the // node itself. This can be changed using a `#set!` predicate that // sets the `injection.include-children` key. "injection.include-children" => include_children = true, _ => {} } } (language_name, content_node, include_children) } fn shrink_and_clear(vec: &mut Vec, capacity: usize) { if vec.len() > capacity { vec.truncate(capacity); vec.shrink_to_fit(); } vec.clear(); }