Structural search & replace of nested try!() causes corruption #11591
Description
rust-analyzer version: 2022-01-31
rustc version: 1.58.1
relevant settings: N/A
Given the following code:
// abcdefghijklmnopqrstuvwxyz
fn main() {
try!(try!("what"));
}running
rust-analyzer ssr 'try!($expr) ==>> $expr?'produces the following absurd result:
// abcdefghijklmnopqrstuvwxyz
fn main() {
ijklmn??;
}I have observed the following properties:
- Varying the inner invocation's input changes how many characters from the initial 'i' is included.
- Inserting linebreaks before the comment slides the window to the right by a corresponding number of characters.
- Inserting linebreaks after the comment does nothing; nor does removing letters from the end of the comment.
- Removing the
?from the replacement rule (or adding more) does not change the corruption. - Adding things to the beginning of the replacement rule (for instance, wrapping it in parentheses) similarly has no effect.
- Wrapping the input with additional
try!()s consumes anotherinput.len()characters for each one you add, although no further?are added beyond the initial two.- This continues past the end of the comment, and will happily generate invalid code (e.g. half of an identifier).
This implies the replacement data is being taken from a location relative to the start of the file, rather than relative to the match itself. I have no idea why this is, and am not sufficiently familiar with rust-analyzer's internals to investigate it further, but knowing these things will probably help with tracking down the problem.