rust/crates/ide/src/interpret_function.rs

51 lines
1.8 KiB
Rust

use hir::Semantics;
use ide_db::{
base_db::{FilePosition, SourceDatabaseExt},
LineIndexDatabase, RootDatabase,
};
use std::{fmt::Write, time::Instant};
use syntax::{algo::ancestors_at_offset, ast, AstNode, TextRange};
// Feature: Interpret Function
//
// |===
// | Editor | Action Name
//
// | VS Code | **rust-analyzer: Interpret Function**
// |===
pub(crate) fn interpret_function(db: &RootDatabase, position: FilePosition) -> String {
let start_time = Instant::now();
let mut result = find_and_interpret(db, position)
.unwrap_or_else(|| "Not inside a function body".to_string());
let duration = Instant::now() - start_time;
writeln!(result, "").unwrap();
writeln!(result, "----------------------").unwrap();
writeln!(result, " Finished in {}s", duration.as_secs_f32()).unwrap();
result
}
fn find_and_interpret(db: &RootDatabase, position: FilePosition) -> Option<String> {
let sema = Semantics::new(db);
let source_file = sema.parse(position.file_id);
let item = ancestors_at_offset(source_file.syntax(), position.offset)
.filter(|it| !ast::MacroCall::can_cast(it.kind()))
.find_map(ast::Item::cast)?;
let def = match item {
ast::Item::Fn(it) => sema.to_def(&it)?,
_ => return None,
};
let span_formatter = |file_id, text_range: TextRange| {
let path = &db
.source_root(db.file_source_root(file_id))
.path_for_file(&file_id)
.map(|x| x.to_string());
let path = path.as_deref().unwrap_or("<unknown file>");
match db.line_index(file_id).try_line_col(text_range.start()) {
Some(line_col) => format!("file://{path}#{}:{}", line_col.line + 1, line_col.col),
None => format!("file://{path} range {:?}", text_range),
}
};
Some(def.eval(db, span_formatter))
}