Use different numbers of #s when expanding documentation comments

Any documentation comments that contain raw-string-looking sequences may
pretty-print invalid code when expanding them, as the current logic
always uses the `r"literal"` form, without appending any `#`s.

This commit calculates the minimum number of `#`s required to wrap a
comment correctly and appends `#`s appropriately.

Fixes #27489.
This commit is contained in:
Barosl Lee 2015-08-04 02:01:15 +09:00
parent 08886499cf
commit 1a8cdc0f2f
3 changed files with 57 additions and 1 deletions

View file

@ -1174,6 +1174,20 @@ impl TokenTree {
}
(&TokenTree::Token(sp, token::DocComment(name)), _) => {
let stripped = strip_doc_comment_decoration(&name.as_str());
// Searches for the occurrences of `"#*` and returns the minimum number of `#`s
// required to wrap the text.
let num_of_hashes = stripped.chars().scan(0, |cnt, x| {
*cnt = if x == '"' {
1
} else if *cnt != 0 && x == '#' {
*cnt + 1
} else {
0
};
Some(*cnt)
}).max().unwrap_or(0);
TokenTree::Delimited(sp, Rc::new(Delimited {
delim: token::Bracket,
open_span: sp,
@ -1181,7 +1195,7 @@ impl TokenTree {
token::Plain)),
TokenTree::Token(sp, token::Eq),
TokenTree::Token(sp, token::Literal(
token::StrRaw(token::intern(&stripped), 0), None))],
token::StrRaw(token::intern(&stripped), num_of_hashes), None))],
close_span: sp,
}))
}