For OutsideLoop we should not suggest add 'block label in if block, or we wiil get another err: block label not supported here.

fixes #123261
This commit is contained in:
surechen 2024-04-08 16:19:09 +08:00
parent 60faa271d9
commit 8fde7e3b64
6 changed files with 290 additions and 45 deletions

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@ -1103,7 +1103,7 @@ pub struct BreakInsideCoroutine<'a> {
pub struct OutsideLoop<'a> {
#[primary_span]
#[label]
pub span: Span,
pub spans: Vec<Span>,
pub name: &'a str,
pub is_break: bool,
#[subdiagnostic]
@ -1115,7 +1115,7 @@ pub struct OutsideLoopSuggestion {
#[suggestion_part(code = "'block: ")]
pub block_span: Span,
#[suggestion_part(code = " 'block")]
pub break_span: Span,
pub break_spans: Vec<Span>,
}
#[derive(Diagnostic)]

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@ -1,3 +1,5 @@
use std::collections::BTreeMap;
use std::fmt;
use Context::*;
use rustc_hir as hir;
@ -25,22 +27,55 @@ enum Context {
Closure(Span),
Coroutine { coroutine_span: Span, kind: hir::CoroutineDesugaring, source: hir::CoroutineSource },
UnlabeledBlock(Span),
UnlabeledIfBlock(Span),
LabeledBlock,
Constant,
}
#[derive(Copy, Clone)]
#[derive(Clone)]
struct BlockInfo {
name: String,
spans: Vec<Span>,
suggs: Vec<Span>,
}
#[derive(PartialEq)]
enum BreakContextKind {
Break,
Continue,
}
impl fmt::Display for BreakContextKind {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
BreakContextKind::Break => "break",
BreakContextKind::Continue => "continue",
}
.fmt(f)
}
}
#[derive(Clone)]
struct CheckLoopVisitor<'a, 'tcx> {
sess: &'a Session,
tcx: TyCtxt<'tcx>,
cx: Context,
// Keep track of a stack of contexts, so that suggestions
// are not made for contexts where it would be incorrect,
// such as adding a label for an `if`.
// e.g. `if 'foo: {}` would be incorrect.
cx_stack: Vec<Context>,
block_breaks: BTreeMap<Span, BlockInfo>,
}
fn check_mod_loops(tcx: TyCtxt<'_>, module_def_id: LocalModDefId) {
tcx.hir().visit_item_likes_in_module(
module_def_id,
&mut CheckLoopVisitor { sess: tcx.sess, tcx, cx: Normal },
);
let mut check = CheckLoopVisitor {
sess: tcx.sess,
tcx,
cx_stack: vec![Normal],
block_breaks: Default::default(),
};
tcx.hir().visit_item_likes_in_module(module_def_id, &mut check);
check.report_outside_loop_error();
}
pub(crate) fn provide(providers: &mut Providers) {
@ -83,6 +118,45 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
fn visit_expr(&mut self, e: &'hir hir::Expr<'hir>) {
match e.kind {
hir::ExprKind::If(cond, then, else_opt) => {
self.visit_expr(cond);
let get_block = |ck_loop: &CheckLoopVisitor<'a, 'hir>,
expr: &hir::Expr<'hir>|
-> Option<&hir::Block<'hir>> {
if let hir::ExprKind::Block(b, None) = expr.kind
&& matches!(
ck_loop.cx_stack.last(),
Some(&Normal)
| Some(&Constant)
| Some(&UnlabeledBlock(_))
| Some(&UnlabeledIfBlock(_))
)
{
Some(b)
} else {
None
}
};
if let Some(b) = get_block(self, then) {
self.with_context(UnlabeledIfBlock(b.span.shrink_to_lo()), |v| {
v.visit_block(b)
});
} else {
self.visit_expr(then);
}
if let Some(else_expr) = else_opt {
if let Some(b) = get_block(self, else_expr) {
self.with_context(UnlabeledIfBlock(b.span.shrink_to_lo()), |v| {
v.visit_block(b)
});
} else {
self.visit_expr(else_expr);
}
}
}
hir::ExprKind::Loop(ref b, _, source, _) => {
self.with_context(Loop(source), |v| v.visit_block(b));
}
@ -101,11 +175,14 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
hir::ExprKind::Block(ref b, Some(_label)) => {
self.with_context(LabeledBlock, |v| v.visit_block(b));
}
hir::ExprKind::Block(ref b, None) if matches!(self.cx, Fn) => {
hir::ExprKind::Block(ref b, None) if matches!(self.cx_stack.last(), Some(&Fn)) => {
self.with_context(Normal, |v| v.visit_block(b));
}
hir::ExprKind::Block(ref b, None)
if matches!(self.cx, Normal | Constant | UnlabeledBlock(_)) =>
if matches!(
self.cx_stack.last(),
Some(&Normal) | Some(&Constant) | Some(&UnlabeledBlock(_))
) =>
{
self.with_context(UnlabeledBlock(b.span.shrink_to_lo()), |v| v.visit_block(b));
}
@ -178,7 +255,12 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
Some(label) => sp_lo.with_hi(label.ident.span.hi()),
None => sp_lo.shrink_to_lo(),
};
self.require_break_cx("break", e.span, label_sp);
self.require_break_cx(
BreakContextKind::Break,
e.span,
label_sp,
self.cx_stack.len() - 1,
);
}
hir::ExprKind::Continue(destination) => {
self.require_label_in_labeled_block(e.span, &destination, "continue");
@ -200,7 +282,12 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
}
Err(_) => {}
}
self.require_break_cx("continue", e.span, e.span)
self.require_break_cx(
BreakContextKind::Continue,
e.span,
e.span,
self.cx_stack.len() - 1,
)
}
_ => intravisit::walk_expr(self, e),
}
@ -212,18 +299,26 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
where
F: FnOnce(&mut CheckLoopVisitor<'a, 'hir>),
{
let old_cx = self.cx;
self.cx = cx;
self.cx_stack.push(cx);
f(self);
self.cx = old_cx;
self.cx_stack.pop();
}
fn require_break_cx(&self, name: &str, span: Span, break_span: Span) {
let is_break = name == "break";
match self.cx {
fn require_break_cx(
&mut self,
br_cx_kind: BreakContextKind,
span: Span,
break_span: Span,
cx_pos: usize,
) {
match self.cx_stack[cx_pos] {
LabeledBlock | Loop(_) => {}
Closure(closure_span) => {
self.sess.dcx().emit_err(BreakInsideClosure { span, closure_span, name });
self.sess.dcx().emit_err(BreakInsideClosure {
span,
closure_span,
name: &br_cx_kind.to_string(),
});
}
Coroutine { coroutine_span, kind, source } => {
let kind = match kind {
@ -239,17 +334,32 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
self.sess.dcx().emit_err(BreakInsideCoroutine {
span,
coroutine_span,
name,
name: &br_cx_kind.to_string(),
kind,
source,
});
}
UnlabeledBlock(block_span) if is_break && block_span.eq_ctxt(break_span) => {
let suggestion = Some(OutsideLoopSuggestion { block_span, break_span });
self.sess.dcx().emit_err(OutsideLoop { span, name, is_break, suggestion });
UnlabeledBlock(block_span)
if br_cx_kind == BreakContextKind::Break && block_span.eq_ctxt(break_span) =>
{
let block = self.block_breaks.entry(block_span).or_insert_with(|| BlockInfo {
name: br_cx_kind.to_string(),
spans: vec![],
suggs: vec![],
});
block.spans.push(span);
block.suggs.push(break_span);
}
Normal | Constant | Fn | UnlabeledBlock(_) => {
self.sess.dcx().emit_err(OutsideLoop { span, name, is_break, suggestion: None });
UnlabeledIfBlock(_) if br_cx_kind == BreakContextKind::Break => {
self.require_break_cx(br_cx_kind, span, break_span, cx_pos - 1);
}
Normal | Constant | Fn | UnlabeledBlock(_) | UnlabeledIfBlock(_) => {
self.sess.dcx().emit_err(OutsideLoop {
spans: vec![span],
name: &br_cx_kind.to_string(),
is_break: br_cx_kind == BreakContextKind::Break,
suggestion: None,
});
}
}
}
@ -261,7 +371,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
cf_type: &str,
) -> bool {
if !span.is_desugaring(DesugaringKind::QuestionMark)
&& self.cx == LabeledBlock
&& self.cx_stack.last() == Some(&LabeledBlock)
&& label.label.is_none()
{
self.sess.dcx().emit_err(UnlabeledInLabeledBlock { span, cf_type });
@ -269,4 +379,18 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
}
false
}
fn report_outside_loop_error(&mut self) {
for (s, block) in &self.block_breaks {
self.sess.dcx().emit_err(OutsideLoop {
spans: block.spans.clone(),
name: &block.name,
is_break: true,
suggestion: Some(OutsideLoopSuggestion {
block_span: *s,
break_spans: block.suggs.clone(),
}),
});
}
}
}

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@ -0,0 +1,31 @@
//@ run-rustfix
#![allow(unused)]
fn main() {
let n = 1;
let m = 2;
let x = 'block: {
if n == 0 {
break 'block 1; //~ ERROR [E0268]
} else {
break 'block 2;
}
};
let y = 'block: {
if n == 0 {
break 'block 1; //~ ERROR [E0268]
}
break 'block 0;
};
let z = 'block: {
if n == 0 {
if m > 1 {
break 'block 3; //~ ERROR [E0268]
}
}
break 'block 1;
};
}

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@ -0,0 +1,31 @@
//@ run-rustfix
#![allow(unused)]
fn main() {
let n = 1;
let m = 2;
let x = {
if n == 0 {
break 1; //~ ERROR [E0268]
} else {
break 2;
}
};
let y = {
if n == 0 {
break 1; //~ ERROR [E0268]
}
break 0;
};
let z = {
if n == 0 {
if m > 1 {
break 3; //~ ERROR [E0268]
}
}
break 1;
};
}

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@ -0,0 +1,59 @@
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/loop-if-else-break-issue-123261.rs:10:13
|
LL | break 1;
| ^^^^^^^ cannot `break` outside of a loop or labeled block
LL | } else {
LL | break 2;
| ^^^^^^^ cannot `break` outside of a loop or labeled block
|
help: consider labeling this block to be able to break within it
|
LL ~ let x = 'block: {
LL | if n == 0 {
LL ~ break 'block 1;
LL | } else {
LL ~ break 'block 2;
|
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/loop-if-else-break-issue-123261.rs:18:13
|
LL | break 1;
| ^^^^^^^ cannot `break` outside of a loop or labeled block
LL | }
LL | break 0;
| ^^^^^^^ cannot `break` outside of a loop or labeled block
|
help: consider labeling this block to be able to break within it
|
LL ~ let y = 'block: {
LL | if n == 0 {
LL ~ break 'block 1;
LL | }
LL ~ break 'block 0;
|
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/loop-if-else-break-issue-123261.rs:26:17
|
LL | break 3;
| ^^^^^^^ cannot `break` outside of a loop or labeled block
...
LL | break 1;
| ^^^^^^^ cannot `break` outside of a loop or labeled block
|
help: consider labeling this block to be able to break within it
|
LL ~ let z = 'block: {
LL | if n == 0 {
LL | if m > 1 {
LL ~ break 'block 3;
LL | }
LL | }
LL ~ break 'block 1;
|
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0268`.

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@ -21,16 +21,21 @@ LL | foo!(());
= note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/break-in-unlabeled-block-in-macro.rs:27:19
--> $DIR/break-in-unlabeled-block-in-macro.rs:33:17
|
LL | foo!(stmt break ());
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
LL | foo!(=> break ());
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/break-in-unlabeled-block-in-macro.rs:38:17
|
help: consider labeling this block to be able to break within it
|
LL ~ 'block: {
LL ~ foo!(stmt break 'block ());
LL | break ()
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
...
LL | bar!()
| ------ in this macro invocation
|
= note: this error originates in the macro `bar` (in Nightly builds, run with -Z macro-backtrace for more info)
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/break-in-unlabeled-block-in-macro.rs:12:11
@ -48,21 +53,16 @@ LL | 'block: { break 'block $e; }
| +++++++ ++++++
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/break-in-unlabeled-block-in-macro.rs:33:17
--> $DIR/break-in-unlabeled-block-in-macro.rs:27:19
|
LL | foo!(=> break ());
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
error[E0268]: `break` outside of a loop or labeled block
--> $DIR/break-in-unlabeled-block-in-macro.rs:38:17
LL | foo!(stmt break ());
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
|
LL | break ()
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
...
LL | bar!()
| ------ in this macro invocation
help: consider labeling this block to be able to break within it
|
LL ~ 'block: {
LL ~ foo!(stmt break 'block ());
|
= note: this error originates in the macro `bar` (in Nightly builds, run with -Z macro-backtrace for more info)
error: aborting due to 6 previous errors