diff options
| -rw-r--r-- | compiler/rustc_parse/src/parser/diagnostics.rs | 16 | ||||
| -rw-r--r-- | compiler/rustc_parse/src/parser/expr.rs | 12 | ||||
| -rw-r--r-- | tests/ui/parser/issue-108495-dec.rs | 39 | ||||
| -rw-r--r-- | tests/ui/parser/issue-108495-dec.stderr | 69 |
4 files changed, 134 insertions, 2 deletions
diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs index b4948dddcc9..33218d3397a 100644 --- a/compiler/rustc_parse/src/parser/diagnostics.rs +++ b/compiler/rustc_parse/src/parser/diagnostics.rs @@ -165,8 +165,6 @@ enum IsStandalone { #[derive(Debug, Copy, Clone, PartialEq, Eq)] enum IncOrDec { Inc, - // FIXME: `i--` recovery isn't implemented yet - #[allow(dead_code)] Dec, } @@ -1357,6 +1355,20 @@ impl<'a> Parser<'a> { self.recover_from_inc_dec(operand_expr, kind, op_span) } + pub(super) fn recover_from_postfix_decrement( + &mut self, + operand_expr: P<Expr>, + op_span: Span, + start_stmt: bool, + ) -> PResult<'a, P<Expr>> { + let kind = IncDecRecovery { + standalone: if start_stmt { IsStandalone::Standalone } else { IsStandalone::Subexpr }, + op: IncOrDec::Dec, + fixity: UnaryFixity::Post, + }; + self.recover_from_inc_dec(operand_expr, kind, op_span) + } + fn recover_from_inc_dec( &mut self, base: P<Expr>, diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 33254d034c9..24d4c17f5d8 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -282,6 +282,18 @@ impl<'a> Parser<'a> { continue; } + if self.prev_token == token::BinOp(token::Minus) + && self.token == token::BinOp(token::Minus) + && self.prev_token.span.between(self.token.span).is_empty() + && !self.look_ahead(1, |tok| tok.can_begin_expr()) + { + let op_span = self.prev_token.span.to(self.token.span); + // Eat the second `-` + self.bump(); + lhs = self.recover_from_postfix_decrement(lhs, op_span, starts_stmt)?; + continue; + } + let op = op.node; // Special cases: if op == AssocOp::As { diff --git a/tests/ui/parser/issue-108495-dec.rs b/tests/ui/parser/issue-108495-dec.rs new file mode 100644 index 00000000000..e0816f84e5c --- /dev/null +++ b/tests/ui/parser/issue-108495-dec.rs @@ -0,0 +1,39 @@ +fn test0() { + let mut i = 0; + let _ = i + i--; //~ ERROR Rust has no postfix decrement operator + // won't suggest since we can not handle the precedences +} + +fn test1() { + let mut i = 0; + let _ = i-- + i--; //~ ERROR Rust has no postfix decrement operator +} + +fn test2() { + let mut i = 0; + let _ = --i + i--; //~ ERROR Rust has no postfix decrement operator +} + +fn test3() { + let mut i = 0; + let _ = i-- + --i; //~ ERROR Rust has no postfix decrement operator +} + +fn test4() { + let mut i = 0; + let _ = (1 + 2 + i)--; //~ ERROR Rust has no postfix decrement operator +} + +fn test5() { + let mut i = 0; + let _ = (i-- + 1) + 2; //~ ERROR Rust has no postfix decrement operator +} + +fn test6(){ + let i=10; + while i != 0 { + i--; //~ ERROR Rust has no postfix decrement operator + } +} + +fn main() {} diff --git a/tests/ui/parser/issue-108495-dec.stderr b/tests/ui/parser/issue-108495-dec.stderr new file mode 100644 index 00000000000..85b29038f7c --- /dev/null +++ b/tests/ui/parser/issue-108495-dec.stderr @@ -0,0 +1,69 @@ +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:3:18 + | +LL | let _ = i + i--; + | ^^ not a valid postfix operator + +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:9:14 + | +LL | let _ = i-- + i--; + | ^^ not a valid postfix operator + | +help: use `-= 1` instead + | +LL | let _ = { let tmp = i; i -= 1; tmp } + i--; + | +++++++++++ ~~~~~~~~~~~~~~~ + +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:14:20 + | +LL | let _ = --i + i--; + | ^^ not a valid postfix operator + +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:19:14 + | +LL | let _ = i-- + --i; + | ^^ not a valid postfix operator + | +help: use `-= 1` instead + | +LL | let _ = { let tmp = i; i -= 1; tmp } + --i; + | +++++++++++ ~~~~~~~~~~~~~~~ + +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:24:24 + | +LL | let _ = (1 + 2 + i)--; + | ^^ not a valid postfix operator + | +help: use `-= 1` instead + | +LL | let _ = { let tmp = (1 + 2 + i); (1 + 2 + i) -= 1; tmp }; + | +++++++++++ ~~~~~~~~~~~~~~~~~~~~~~~~~ + +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:29:15 + | +LL | let _ = (i-- + 1) + 2; + | ^^ not a valid postfix operator + | +help: use `-= 1` instead + | +LL | let _ = ({ let tmp = i; i -= 1; tmp } + 1) + 2; + | +++++++++++ ~~~~~~~~~~~~~~~ + +error: Rust has no postfix decrement operator + --> $DIR/issue-108495-dec.rs:35:10 + | +LL | i--; + | ^^ not a valid postfix operator + | +help: use `-= 1` instead + | +LL | i -= 1; + | ~~~~ + +error: aborting due to 7 previous errors + |