From 380fa264132ad481e73cbbf0f3a0feefd99a1d78 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=AE=B8=E6=9D=B0=E5=8F=8B=20Jieyou=20Xu=20=28Joe=29?=
<jieyouxu@outlook.com>
Date: Tue, 14 Feb 2023 17:31:58 +0800
Subject: [PATCH 1/3] Don't recover lifetimes/labels containing emojis as
character literals
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Note that at the time of this commit, `unic-emoji-char` seems to have
data tables only up to Unicode 5.0, but Unicode is already newer than
this.
A newer emoji such as `🥺` will not be recognized as an emoji
but older emojis such as `🐱` will.
---
compiler/rustc_errors/src/lib.rs | 2 +
compiler/rustc_lexer/src/lib.rs | 43 +++++++---
compiler/rustc_parse/src/lexer/mod.rs | 9 +-
.../lexer/issue-108019-bad-emoji-recovery.rs | 45 ++++++++++
.../issue-108019-bad-emoji-recovery.stderr | 86 +++++++++++++++++++
5 files changed, 173 insertions(+), 12 deletions(-)
create mode 100644 tests/ui/lexer/issue-108019-bad-emoji-recovery.rs
create mode 100644 tests/ui/lexer/issue-108019-bad-emoji-recovery.stderr
diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs
index 83b733d4c0677..b310b191d5273 100644
--- a/compiler/rustc_errors/src/lib.rs
+++ b/compiler/rustc_errors/src/lib.rs
@@ -471,6 +471,8 @@ pub enum StashKey {
/// When an invalid lifetime e.g. `'2` should be reinterpreted
/// as a char literal in the parser
LifetimeIsChar,
+ /// When an invalid lifetime e.g. `'🐱` contains emoji.
+ LifetimeContainsEmoji,
/// Maybe there was a typo where a comma was forgotten before
/// FRU syntax
MaybeFruTypo,
diff --git a/compiler/rustc_lexer/src/lib.rs b/compiler/rustc_lexer/src/lib.rs
index 6e815863d06ff..e6f04fe0aaa63 100644
--- a/compiler/rustc_lexer/src/lib.rs
+++ b/compiler/rustc_lexer/src/lib.rs
@@ -95,7 +95,7 @@ pub enum TokenKind {
Literal { kind: LiteralKind, suffix_start: u32 },
/// "'a"
- Lifetime { starts_with_number: bool },
+ Lifetime { starts_with_number: bool, contains_emoji: bool },
// One-char tokens:
/// ";"
@@ -630,7 +630,13 @@ impl Cursor<'_> {
// If the first symbol is valid for identifier, it can be a lifetime.
// Also check if it's a number for a better error reporting (so '0 will
// be reported as invalid lifetime and not as unterminated char literal).
- is_id_start(self.first()) || self.first().is_digit(10)
+ // We also have to account for potential `'🐱` emojis to avoid reporting
+ // it as an unterminated char literal.
+ is_id_start(self.first())
+ || self.first().is_digit(10)
+ // FIXME(#108019): `unic-emoji-char` seems to have data tables only up to Unicode
+ // 5.0, but Unicode is already newer than this.
+ || unic_emoji_char::is_emoji(self.first())
};
if !can_be_a_lifetime {
@@ -643,16 +649,33 @@ impl Cursor<'_> {
return Literal { kind, suffix_start };
}
- // Either a lifetime or a character literal with
- // length greater than 1.
+ // Either a lifetime or a character literal.
let starts_with_number = self.first().is_digit(10);
+ let mut contains_emoji = false;
- // Skip the literal contents.
- // First symbol can be a number (which isn't a valid identifier start),
- // so skip it without any checks.
- self.bump();
- self.eat_while(is_id_continue);
+ // FIXME(#108019): `unic-emoji-char` seems to have data tables only up to Unicode
+ // 5.0, but Unicode is already newer than this.
+ if unic_emoji_char::is_emoji(self.first()) {
+ contains_emoji = true;
+ } else {
+ // Skip the literal contents.
+ // First symbol can be a number (which isn't a valid identifier start),
+ // so skip it without any checks.
+ self.bump();
+ }
+ self.eat_while(|c| {
+ if is_id_continue(c) {
+ true
+ // FIXME(#108019): `unic-emoji-char` seems to have data tables only up to Unicode
+ // 5.0, but Unicode is already newer than this.
+ } else if unic_emoji_char::is_emoji(c) {
+ contains_emoji = true;
+ true
+ } else {
+ false
+ }
+ });
// Check if after skipping literal contents we've met a closing
// single quote (which means that user attempted to create a
@@ -662,7 +685,7 @@ impl Cursor<'_> {
let kind = Char { terminated: true };
Literal { kind, suffix_start: self.pos_within_token() }
} else {
- Lifetime { starts_with_number }
+ Lifetime { starts_with_number, contains_emoji }
}
}
diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index bd998ed91d977..37449aaabed8b 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -200,16 +200,21 @@ impl<'a> StringReader<'a> {
};
token::Literal(token::Lit { kind, symbol, suffix })
}
- rustc_lexer::TokenKind::Lifetime { starts_with_number } => {
+ rustc_lexer::TokenKind::Lifetime { starts_with_number, contains_emoji } => {
// Include the leading `'` in the real identifier, for macro
// expansion purposes. See #12512 for the gory details of why
// this is necessary.
let lifetime_name = self.str_from(start);
if starts_with_number {
let span = self.mk_sp(start, self.pos);
- let mut diag = self.sess.struct_err("lifetimes cannot start with a number");
+ let mut diag = self.sess.struct_err("lifetimes or labels cannot start with a number");
diag.set_span(span);
diag.stash(span, StashKey::LifetimeIsChar);
+ } else if contains_emoji {
+ let span = self.mk_sp(start, self.pos);
+ let mut diag = self.sess.struct_err("lifetimes or labels cannot contain emojis");
+ diag.set_span(span);
+ diag.stash(span, StashKey::LifetimeContainsEmoji);
}
let ident = Symbol::intern(lifetime_name);
token::Lifetime(ident)
diff --git a/tests/ui/lexer/issue-108019-bad-emoji-recovery.rs b/tests/ui/lexer/issue-108019-bad-emoji-recovery.rs
new file mode 100644
index 0000000000000..f0f8622456010
--- /dev/null
+++ b/tests/ui/lexer/issue-108019-bad-emoji-recovery.rs
@@ -0,0 +1,45 @@
+#![allow(unused_labels)]
+
+// FIXME(#108019): outdated Unicode table
+// fn foo() {
+// '🥺 loop {
+// break
+// }
+// }
+
+fn bar() {
+ '🐱 loop {
+ //~^ ERROR labeled expression must be followed by `:`
+ //~| ERROR lifetimes or labels cannot contain emojis
+ break
+ }
+}
+
+fn qux() {
+ 'a🐱 loop {
+ //~^ ERROR labeled expression must be followed by `:`
+ //~| ERROR lifetimes or labels cannot contain emojis
+ break
+ }
+}
+
+fn quux() {
+ '1🐱 loop {
+ //~^ ERROR labeled expression must be followed by `:`
+ //~| ERROR lifetimes or labels cannot start with a number
+ break
+ }
+}
+
+fn x<'🐱>() -> &'🐱 () {
+ //~^ ERROR lifetimes or labels cannot contain emojis
+ //~| ERROR lifetimes or labels cannot contain emojis
+ &()
+}
+
+fn y() {
+ 'a🐱: loop {}
+ //~^ ERROR lifetimes or labels cannot contain emojis
+}
+
+fn main() {}
diff --git a/tests/ui/lexer/issue-108019-bad-emoji-recovery.stderr b/tests/ui/lexer/issue-108019-bad-emoji-recovery.stderr
new file mode 100644
index 0000000000000..be77ffdea349f
--- /dev/null
+++ b/tests/ui/lexer/issue-108019-bad-emoji-recovery.stderr
@@ -0,0 +1,86 @@
+error: labeled expression must be followed by `:`
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:11:5
+ |
+LL | '🐱 loop {
+ | ^--- help: add `:` after the label
+ | |
+ | _____the label
+ | |
+LL | |
+LL | |
+LL | | break
+LL | | }
+ | |_____^
+ |
+ = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: labeled expression must be followed by `:`
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:19:5
+ |
+LL | 'a🐱 loop {
+ | ^---- help: add `:` after the label
+ | |
+ | _____the label
+ | |
+LL | |
+LL | |
+LL | | break
+LL | | }
+ | |_____^
+ |
+ = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: labeled expression must be followed by `:`
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:27:5
+ |
+LL | '1🐱 loop {
+ | ^---- help: add `:` after the label
+ | |
+ | _____the label
+ | |
+LL | |
+LL | |
+LL | | break
+LL | | }
+ | |_____^
+ |
+ = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: lifetimes or labels cannot contain emojis
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:11:5
+ |
+LL | '🐱 loop {
+ | ^^^
+
+error: lifetimes or labels cannot contain emojis
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:19:5
+ |
+LL | 'a🐱 loop {
+ | ^^^^
+
+error: lifetimes or labels cannot start with a number
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:27:5
+ |
+LL | '1🐱 loop {
+ | ^^^^
+
+error: lifetimes or labels cannot contain emojis
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:34:6
+ |
+LL | fn x<'🐱>() -> &'🐱 () {
+ | ^^^
+
+error: lifetimes or labels cannot contain emojis
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:34:16
+ |
+LL | fn x<'🐱>() -> &'🐱 () {
+ | ^^^
+
+error: lifetimes or labels cannot contain emojis
+ --> $DIR/issue-108019-bad-emoji-recovery.rs:41:5
+ |
+LL | 'a🐱: loop {}
+ | ^^^^
+
+error: aborting due to 9 previous errors
+
From 98b82aedba3f3f581e89df54352914b27f42c6f7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=AE=B8=E6=9D=B0=E5=8F=8B=20Jieyou=20Xu=20=28Joe=29?=
<jieyouxu@outlook.com>
Date: Tue, 14 Feb 2023 18:17:59 +0800
Subject: [PATCH 2/3] Update numeric lifetime test
---
tests/ui/parser/numeric-lifetime.rs | 4 ++--
tests/ui/parser/numeric-lifetime.stderr | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/tests/ui/parser/numeric-lifetime.rs b/tests/ui/parser/numeric-lifetime.rs
index 2d82354c62cca..a082a8a44df2a 100644
--- a/tests/ui/parser/numeric-lifetime.rs
+++ b/tests/ui/parser/numeric-lifetime.rs
@@ -1,6 +1,6 @@
struct S<'1> { s: &'1 usize }
-//~^ ERROR lifetimes cannot start with a number
-//~| ERROR lifetimes cannot start with a number
+//~^ ERROR lifetimes or labels cannot start with a number
+//~| ERROR lifetimes or labels cannot start with a number
fn main() {
// verify that the parse error doesn't stop type checking
let x: usize = "";
diff --git a/tests/ui/parser/numeric-lifetime.stderr b/tests/ui/parser/numeric-lifetime.stderr
index 7c1bcb7263171..66e35dca92319 100644
--- a/tests/ui/parser/numeric-lifetime.stderr
+++ b/tests/ui/parser/numeric-lifetime.stderr
@@ -6,13 +6,13 @@ LL | let x: usize = "";
| |
| expected due to this
-error: lifetimes cannot start with a number
+error: lifetimes or labels cannot start with a number
--> $DIR/numeric-lifetime.rs:1:10
|
LL | struct S<'1> { s: &'1 usize }
| ^^
-error: lifetimes cannot start with a number
+error: lifetimes or labels cannot start with a number
--> $DIR/numeric-lifetime.rs:1:20
|
LL | struct S<'1> { s: &'1 usize }
From e3f9db5fc319c6d8eee5d47d216ea6a426070c41 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=AE=B8=E6=9D=B0=E5=8F=8B=20Jieyou=20Xu=20=28Joe=29?=
<jieyouxu@outlook.com>
Date: Tue, 14 Feb 2023 23:24:55 +0800
Subject: [PATCH 3/3] Update lexer lifetime test
---
compiler/rustc_lexer/src/tests.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/compiler/rustc_lexer/src/tests.rs b/compiler/rustc_lexer/src/tests.rs
index e4c1787f2ccef..670d64fb983f5 100644
--- a/compiler/rustc_lexer/src/tests.rs
+++ b/compiler/rustc_lexer/src/tests.rs
@@ -235,7 +235,7 @@ fn lifetime() {
check_lexing(
"'abc",
expect![[r#"
- Token { kind: Lifetime { starts_with_number: false }, len: 4 }
+ Token { kind: Lifetime { starts_with_number: false, contains_emoji: false }, len: 4 }
"#]],
);
}