crates/folding/src/lib.rs
use base_db::{Document, DocumentData};
use rowan::{ast::AstNode, TextRange};
use syntax::{
bibtex::{self, HasDelims, HasName},
latex,
};
#[derive(Debug)]
pub struct FoldingRange {
pub range: TextRange,
pub kind: FoldingRangeKind,
}
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Hash)]
pub enum FoldingRangeKind {
Section,
Environment,
Entry,
}
pub fn find_all(document: &Document) -> Vec<FoldingRange> {
let mut builder = FoldingBuilder::default();
if let DocumentData::Tex(data) = &document.data {
for node in data.root_node().descendants() {
if let Some(section) = latex::Section::cast(node.clone()) {
builder.fold_section(§ion);
} else if let Some(item) = latex::EnumItem::cast(node.clone()) {
builder.fold_enum_item(&item);
} else if let Some(env) = latex::Environment::cast(node) {
builder.fold_environment(env);
}
}
} else if let DocumentData::Bib(data) = &document.data {
for node in data.root_node().descendants() {
if let Some(entry) = bibtex::Entry::cast(node.clone()) {
builder.fold_entry(&entry);
} else if let Some(string) = bibtex::StringDef::cast(node) {
builder.fold_entry(&string);
}
}
}
builder.ranges
}
#[derive(Debug, Default)]
struct FoldingBuilder {
ranges: Vec<FoldingRange>,
}
impl FoldingBuilder {
fn fold_section(&mut self, section: &latex::Section) -> Option<()> {
let start = section
.name()
.map(|name| latex::small_range(&name).end())
.or_else(|| section.command().map(|cmd| cmd.text_range().end()))?;
let end = section.syntax().text_range().end();
self.ranges.push(FoldingRange {
range: TextRange::new(start, end),
kind: FoldingRangeKind::Section,
});
Some(())
}
fn fold_enum_item(&mut self, item: &latex::EnumItem) -> Option<()> {
let start = item
.label()
.map(|label| latex::small_range(&label).end())
.or_else(|| item.command().map(|cmd| cmd.text_range().end()))?;
let end = item.syntax().text_range().end();
self.ranges.push(FoldingRange {
range: TextRange::new(start, end),
kind: FoldingRangeKind::Section,
});
Some(())
}
fn fold_environment(&mut self, env: latex::Environment) -> Option<()> {
let start = latex::small_range(&env.begin()?).end();
let end = latex::small_range(&env.end()?).start();
self.ranges.push(FoldingRange {
range: TextRange::new(start, end),
kind: FoldingRangeKind::Environment,
});
Some(())
}
fn fold_entry(&mut self, entry: &(impl HasName + HasDelims)) -> Option<()> {
let start = entry.name_token()?.text_range().end();
let end = entry.right_delim_token()?.text_range().start();
self.ranges.push(FoldingRange {
range: TextRange::new(start, end),
kind: FoldingRangeKind::Entry,
});
Some(())
}
}
#[cfg(test)]
mod tests;