From 6001c50cac411d7a889c4dfd176d6dda8b4b181f Mon Sep 17 00:00:00 2001 From: Nicholas Nethercote Date: Thu, 7 Dec 2023 09:53:08 +1100 Subject: [PATCH] Detect `NulInCStr` error earlier. By making it an `EscapeError` instead of a `LitError`. This makes it like the other errors produced when checking string literals contents, e.g. for invalid escape sequences or bare CR chars. NOTE: this means these errors are issued earlier, before expansion, which changes behaviour. It will be possible to move the check back to the later point if desired. If that happens, it's likely that all the string literal contents checks will be delayed together. One nice thing about this: the old approach had some code in `report_lit_error` to calculate the span of the nul char from a range. This code used a hardwired `+2` to account for the `c"` at the start of a C string literal, but this should have changed to a `+3` for raw C string literals to account for the `cr"`, which meant that the caret in `cr"` nul error messages was one short of where it should have been. The new approach doesn't need any of this and avoids the off-by-one error. --- crates/parser/src/lexed_str.rs | 1 + crates/syntax/src/validation.rs | 3 +++ 2 files changed, 4 insertions(+) diff --git a/crates/parser/src/lexed_str.rs b/crates/parser/src/lexed_str.rs index b9e7566fdf9bc..3753a1beb7a8e 100644 --- a/crates/parser/src/lexed_str.rs +++ b/crates/parser/src/lexed_str.rs @@ -371,6 +371,7 @@ fn error_to_diagnostic_message(error: EscapeError, mode: Mode) -> &'static str { "non-ASCII character in byte string literal" } EscapeError::NonAsciiCharInByte => "non-ASCII character in raw byte string literal", + EscapeError::NulInCStr => "null character in C string literal", EscapeError::UnskippedWhitespaceWarning => "", EscapeError::MultipleSkippedLinesWarning => "", } diff --git a/crates/syntax/src/validation.rs b/crates/syntax/src/validation.rs index eabbda2c3983c..0504f67c9dc7e 100644 --- a/crates/syntax/src/validation.rs +++ b/crates/syntax/src/validation.rs @@ -106,6 +106,9 @@ fn rustc_unescape_error_to_string(err: unescape::EscapeError) -> (&'static str, EE::NonAsciiCharInByte => { "Byte literals must not contain non-ASCII characters" } + EE::NulInCStr => { + "C strings literals must not contain null characters" + } EE::UnskippedWhitespaceWarning => "Whitespace after this escape is not skipped", EE::MultipleSkippedLinesWarning => "Multiple lines are skipped by this escape",