diff options
| -rw-r--r-- | compiler/rustc_hir_typeck/src/pat.rs | 34 |
1 files changed, 15 insertions, 19 deletions
diff --git a/compiler/rustc_hir_typeck/src/pat.rs b/compiler/rustc_hir_typeck/src/pat.rs index 482c4ed3af3..5a2fed13d2b 100644 --- a/compiler/rustc_hir_typeck/src/pat.rs +++ b/compiler/rustc_hir_typeck/src/pat.rs @@ -155,34 +155,33 @@ enum AdjustMode { #[derive(Clone, Copy, Debug, PartialEq, Eq)] enum MutblCap { /// Mutability restricted to immutable. + Not, + + /// Mutability restricted to immutable, but only because of the pattern + /// (not the scrutinee type). /// /// The contained span, if present, points to an `&` pattern /// that is the reason for the restriction, /// and which will be reported in a diagnostic. /// (Said diagnostic is shown only if /// replacing the `&` pattern with `&mut` would allow the code to compile.) - /// - /// (Outer [`Option`] is for whether to show the diagnostic, - /// inner [`Option`] is for whether we have a span we can report) - Not(Option<Option<Span>>), + WeaklyNot(Option<Span>), + /// No restriction on mutability Mut, } impl MutblCap { - fn cap_mutbl_to_not(self, span: Option<Option<Span>>) -> Self { - if let Some(s) = span - && self != MutblCap::Not(None) - { - MutblCap::Not(Some(s)) - } else { - MutblCap::Not(None) + fn cap_to_weakly_not(self, span: Option<Span>) -> Self { + match self { + MutblCap::Not => MutblCap::Not, + _ => MutblCap::WeaklyNot(span), } } fn as_mutbl(self) -> Mutability { match self { - MutblCap::Not(_) => Mutability::Not, + MutblCap::Not | MutblCap::WeaklyNot(_) => Mutability::Not, MutblCap::Mut => Mutability::Mut, } } @@ -357,7 +356,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { if pat.span.at_least_rust_2024() && self.tcx.features().ref_pat_eat_one_layer_2024 { let max_ref_mutbl = if ref_pat_mutbl == Mutability::Not { - max_ref_mutbl.cap_mutbl_to_not(Some(ref_span)) + max_ref_mutbl.cap_to_weakly_not(ref_span) } else { max_ref_mutbl }; @@ -505,7 +504,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { if pat.span.at_least_rust_2024() && self.tcx.features().ref_pat_eat_one_layer_2024 { def_br = def_br.cap_ref_mutability(max_ref_mutability.as_mutbl()); if def_br == ByRef::Yes(Mutability::Not) { - max_ref_mutability = max_ref_mutability.cap_mutbl_to_not(None); + max_ref_mutability = MutblCap::Not; } } @@ -752,7 +751,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }; if bm.0 == ByRef::Yes(Mutability::Mut) - && let MutblCap::Not(Some(and_pat_span)) = pat_info.max_ref_mutbl + && let MutblCap::WeaklyNot(and_pat_span) = pat_info.max_ref_mutbl { let mut err = struct_span_code_err!( self.tcx.dcx(), @@ -2215,10 +2214,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { && self.tcx.features().ref_pat_eat_one_layer_2024) || self.tcx.features().ref_pat_everywhere) { - PatInfo { - max_ref_mutbl: pat_info.max_ref_mutbl.cap_mutbl_to_not(None), - ..pat_info - } + PatInfo { max_ref_mutbl: MutblCap::Not, ..pat_info } } else { pat_info }; |