rust-lang/rust-analyzer

matching_brace function not correct when jumping from open brace to close brace

Open

#1942 opened on Oct 2, 2019

View on GitHub
 (8 comments) (0 reactions) (0 assignees)Rust (14,924 stars) (1,726 forks)batch import
E-has-instructionsE-mediumS-actionablegood first issue

Description

https://github.com/rust-analyzer/rust-analyzer/blob/31f22d85491d9e7eaadf5fd4f9754c83fc0f3ea6/crates/ra_ide_api/src/matching_brace.rs#L41

swap the order of do_check parameters the makes the test case failed

do_check("struct Foo <|>{ a: i32, }", "struct Foo { a: i32, }<|>");

this matching behavior should be symmetrical

https://github.com/rust-analyzer/rust-analyzer/blob/31f22d85491d9e7eaadf5fd4f9754c83fc0f3ea6/crates/ra_ide_api/src/matching_brace.rs#L18-L19

if the matching node is a left brace, we use start(), if the matching node is a right brace, we should use end()

Contributor guide

Tech stack
rust
Domain
developer experiencetooling
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Rustrust analyzer codebase
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
80
Research direction
The bug is in crates/ra ide api/src/matching brace.rs. The function do check currently uses start() for left brace but should use end() for right brace to ensure symmetry. The fix involves swapping the parameter order in the test case and adjusting the check for right brace to use end(). No linked PRs or maintainer questions; the issue is self contained.