mathieu/os-rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Suggest adding {} for 'label: non_block_expr

Browse source
This commit is contained in:
Maybe Waffle 2022-06-05 16:45:29 +04:00
parent a2da4af33c
commit f21c0a274e
5 changed files with 123 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

30
compiler/rustc_parse/src/parser/expr.rs
View file

@ -13,10 +13,12 @@ use rustc_ast::tokenstream::Spacing;
use rustc_ast::util::classify;
use rustc_ast::util::literal::LitError;
use rustc_ast::util::parser::{prec_let_scrutinee_needs_par, AssocOp, Fixity};
use rustc_ast::StmtKind;
use rustc_ast::{self as ast, AttrStyle, AttrVec, CaptureBy, ExprField, Lit, UnOp, DUMMY_NODE_ID};
use rustc_ast::{AnonConst, BinOp, BinOpKind, FnDecl, FnRetTy, MacCall, Param, Ty, TyKind};
use rustc_ast::{Arm, Async, BlockCheckMode, Expr, ExprKind, Label, Movability, RangeLimits};
use rustc_ast_pretty::pprust;
use rustc_data_structures::thin_vec::ThinVec;
use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, PResult};
use rustc_session::lint::builtin::BREAK_WITH_LABEL_AND_LOOP;
use rustc_session::lint::BuiltinLintDiagnostics;
@ -1548,9 +1550,33 @@ impl<'a> Parser<'a> {
Ok(self.mk_expr_err(lo))
} else {
let msg = "expected `while`, `for`, `loop` or `{` after a label";
self.struct_span_err(self.token.span, msg).span_label(self.token.span, msg).emit();
let mut err = self.struct_span_err(self.token.span, msg);
err.span_label(self.token.span, msg);
// Continue as an expression in an effort to recover on `'label: non_block_expr`.
self.parse_expr()
let expr = self.parse_expr().map(|expr| {
let span = expr.span;
let sugg_msg = "consider enclosing expression in a block";
let suggestions = vec![
(span.shrink_to_lo(), "{".to_owned()),
(span.shrink_to_hi(), "}".to_owned()),
];
err.multipart_suggestion_verbose(
sugg_msg,
suggestions,
Applicability::MachineApplicable,
);
// Replace `'label: non_block_expr` with `'label: {non_block_expr}` in order to supress future errors about `break 'label`.
let stmt = self.mk_stmt(span, StmtKind::Expr(expr));
let blk = self.mk_block(vec![stmt], BlockCheckMode::Default, span);
self.mk_expr(span, ExprKind::Block(blk, label), ThinVec::new())
});
err.emit();
expr
}?;
if !ate_colon && consume_colon {

5
src/test/ui/parser/labeled-no-colon-expr.stderr
View file

@ -47,6 +47,11 @@ error: expected `while`, `for`, `loop` or `{` after a label
|
LL | 'l4 0;
| ^ expected `while`, `for`, `loop` or `{` after a label
|
help: consider enclosing expression in a block
|
LL | 'l4 {0};
| + +
error: labeled expression must be followed by `:`
--> $DIR/labeled-no-colon-expr.rs:8:9

25
src/test/ui/parser/recover-labeled-non-block-expr.fixed Normal file
View file

@ -0,0 +1,25 @@
// run-rustfix
#![feature(label_break_value)]
fn main() {
#[allow(unused_labels)]
'label: {1 + 1}; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
'label: {match () { () => break 'label, }}; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
let x = 1;
let _i = 'label: {match x { //~ ERROR expected `while`, `for`, `loop` or `{` after a label
0 => 42,
1 if false => break 'label 17,
1 => {
if true {
break 'label 13
} else {
break 'label 0;
}
}
_ => 1,
}};
let other = 3;
let _val = 'label: {(1, if other == 3 { break 'label (2, 3) } else { other })}; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
}

22
src/test/ui/parser/recover-labeled-non-block-expr.rs
View file

@ -1,5 +1,25 @@
// run-rustfix
#![feature(label_break_value)]
fn main() {
#[allow(unused_labels)]
'label: 1 + 1; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
let _recovery_witness: () = 0; //~ ERROR mismatched types
'label: match () { () => break 'label, }; //~ ERROR expected `while`, `for`, `loop` or `{` after a label
let x = 1;
let _i = 'label: match x { //~ ERROR expected `while`, `for`, `loop` or `{` after a label
0 => 42,
1 if false => break 'label 17,
1 => {
if true {
break 'label 13
} else {
break 'label 0;
}
}
_ => 1,
};
let other = 3;
let _val = 'label: (1, if other == 3 { break 'label (2, 3) } else { other }); //~ ERROR expected `while`, `for`, `loop` or `{` after a label
}

54
src/test/ui/parser/recover-labeled-non-block-expr.stderr
View file

@ -1,17 +1,51 @@
error: expected `while`, `for`, `loop` or `{` after a label
--> $DIR/recover-labeled-non-block-expr.rs:2:13
--> $DIR/recover-labeled-non-block-expr.rs:5:13
|
LL | 'label: 1 + 1;
| ^ expected `while`, `for`, `loop` or `{` after a label
error[E0308]: mismatched types
--> $DIR/recover-labeled-non-block-expr.rs:4:33
|
LL | let _recovery_witness: () = 0;
| -- ^ expected `()`, found integer
| |
| expected due to this
help: consider enclosing expression in a block
|
LL | 'label: {1 + 1};
| + +
error: aborting due to 2 previous errors
error: expected `while`, `for`, `loop` or `{` after a label
--> $DIR/recover-labeled-non-block-expr.rs:7:13
|
LL | 'label: match () { () => break 'label, };
| ^^^^^ expected `while`, `for`, `loop` or `{` after a label
|
help: consider enclosing expression in a block
|
LL | 'label: {match () { () => break 'label, }};
| + +
error: expected `while`, `for`, `loop` or `{` after a label
--> $DIR/recover-labeled-non-block-expr.rs:10:22
|
LL | let _i = 'label: match x {
| ^^^^^ expected `while`, `for`, `loop` or `{` after a label
|
help: consider enclosing expression in a block
|
LL ~ let _i = 'label: {match x {
LL | 0 => 42,
LL | 1 if false => break 'label 17,
LL | 1 => {
LL | if true {
LL | break 'label 13
...
error: expected `while`, `for`, `loop` or `{` after a label
--> $DIR/recover-labeled-non-block-expr.rs:24:24
|
LL | let _val = 'label: (1, if other == 3 { break 'label (2, 3) } else { other });
| ^ expected `while`, `for`, `loop` or `{` after a label
|
help: consider enclosing expression in a block
|
LL | let _val = 'label: {(1, if other == 3 { break 'label (2, 3) } else { other })};
| + +
error: aborting due to 4 previous errors
For more information about this error, try `rustc --explain E0308`.