From ed58c01959bc69b42943292d7d5a8e86a821747e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Matthias=20Kr=C3=BCger?= Date: Sat, 4 Feb 2023 13:27:53 +0100 Subject: [PATCH] don't point at nonexisting code beyond EOF when warning about unused delims Previously we would show this: ``` warning: unnecessary braces around block return value --> /tmp/bad.rs:1:8 | 1 | fn a(){{{ | ^ ^ | = note: `#[warn(unused_braces)]` on by default help: remove these braces | 1 - fn a(){{{ 1 + fn a(){{ | ``` which is now hidden in this case. We would create a span spanning between the pair of redundant {}s but there is only EOF instead of the `}` so we would previously point at nothing. This would cause the debug assertion ice to trigger. I would have loved to just only point at the second delim and say "you can remove that" but I'm not sure how to do that without refactoring the entire diagnostic which seems tricky. :( But given that this does not seem to regress any other tests we have, I think this edge-casey enough be acceptable. Fixes https://github.com/rust-lang/rust/issues/107423 r? @compiler-errors --- compiler/rustc_lint/src/unused.rs | 4 +++ ...ue-107423-unused-delim-only-one-no-pair.rs | 7 ++++ ...07423-unused-delim-only-one-no-pair.stderr | 32 +++++++++++++++++++ 3 files changed, 43 insertions(+) create mode 100644 tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.rs create mode 100644 tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.stderr diff --git a/compiler/rustc_lint/src/unused.rs b/compiler/rustc_lint/src/unused.rs index 4c9b3df2dbd33..2f54227c425b8 100644 --- a/compiler/rustc_lint/src/unused.rs +++ b/compiler/rustc_lint/src/unused.rs @@ -661,6 +661,10 @@ trait UnusedDelimLint { keep_space: (bool, bool), ) { let primary_span = if let Some((lo, hi)) = spans { + if hi.is_empty() { + // do not point at delims that do not exist + return; + } MultiSpan::from(vec![lo, hi]) } else { MultiSpan::from(value_span) diff --git a/tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.rs b/tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.rs new file mode 100644 index 0000000000000..4003ee37ca1ea --- /dev/null +++ b/tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.rs @@ -0,0 +1,7 @@ +// check that we don't generate a span that points beyond EOF + +// error-pattern: unclosed delimiter +// error-pattern: unclosed delimiter +// error-pattern: unclosed delimiter + +fn a(){{{ diff --git a/tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.stderr b/tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.stderr new file mode 100644 index 0000000000000..0479035171e89 --- /dev/null +++ b/tests/ui/malformed/issue-107423-unused-delim-only-one-no-pair.stderr @@ -0,0 +1,32 @@ +error: this file contains an unclosed delimiter + --> $DIR/issue-107423-unused-delim-only-one-no-pair.rs:7:11 + | +LL | fn a(){{{ + | --- ^ + | ||| + | ||unclosed delimiter + | |unclosed delimiter + | unclosed delimiter + +error: this file contains an unclosed delimiter + --> $DIR/issue-107423-unused-delim-only-one-no-pair.rs:7:11 + | +LL | fn a(){{{ + | --- ^ + | ||| + | ||unclosed delimiter + | |unclosed delimiter + | unclosed delimiter + +error: this file contains an unclosed delimiter + --> $DIR/issue-107423-unused-delim-only-one-no-pair.rs:7:11 + | +LL | fn a(){{{ + | --- ^ + | ||| + | ||unclosed delimiter + | |unclosed delimiter + | unclosed delimiter + +error: aborting due to 3 previous errors +