mirror of
https://github.com/rust-lang/rust.git
synced 2024-12-05 13:13:40 +00:00
Add SnippetProvider
This commit is contained in:
parent
0432d4db35
commit
98860ab890
@ -8,7 +8,9 @@
|
||||
// option. This file may not be copied, modified, or distributed
|
||||
// except according to those terms.
|
||||
|
||||
use std::rc::Rc;
|
||||
use std::cmp;
|
||||
use std::mem;
|
||||
|
||||
use strings::string_buffer::StringBuffer;
|
||||
use syntax::{ast, visit};
|
||||
@ -47,6 +49,32 @@ fn is_extern_crate(item: &ast::Item) -> bool {
|
||||
}
|
||||
}
|
||||
|
||||
/// Creates a string slice corresponding to the specified span.
|
||||
pub struct SnippetProvider {
|
||||
/// A pointer to the content of the file we are formatting.
|
||||
big_snippet: *const Rc<String>,
|
||||
/// A position of the start of `big_snippet`, used as an offset.
|
||||
start_pos: usize,
|
||||
}
|
||||
|
||||
impl SnippetProvider {
|
||||
pub fn span_to_snippet(&self, span: Span) -> Option<&str> {
|
||||
let start_index = span.lo().to_usize().checked_sub(self.start_pos)?;
|
||||
let end_index = span.hi().to_usize().checked_sub(self.start_pos)?;
|
||||
unsafe { Some(&(*self.big_snippet)[start_index..end_index]) }
|
||||
}
|
||||
|
||||
pub fn from_codemap(codemap: &CodeMap, span: Span) -> Self {
|
||||
let filemap = codemap.lookup_char_pos(span.lo()).file;
|
||||
let big_snippet = unsafe { mem::transmute(&filemap.src) };
|
||||
let start_pos = filemap.start_pos.to_usize();
|
||||
SnippetProvider {
|
||||
big_snippet,
|
||||
start_pos,
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
pub struct FmtVisitor<'a> {
|
||||
pub parse_session: &'a ParseSess,
|
||||
pub codemap: &'a CodeMap,
|
||||
|
Loading…
Reference in New Issue
Block a user