diff options
Diffstat (limited to 'compiler/rustc_pattern_analysis/src/rustc.rs')
| -rw-r--r-- | compiler/rustc_pattern_analysis/src/rustc.rs | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/compiler/rustc_pattern_analysis/src/rustc.rs b/compiler/rustc_pattern_analysis/src/rustc.rs index 0085f0ab656..4e9e17dc24e 100644 --- a/compiler/rustc_pattern_analysis/src/rustc.rs +++ b/compiler/rustc_pattern_analysis/src/rustc.rs @@ -445,6 +445,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { let cx = self; let ty = cx.reveal_opaque_ty(pat.ty); let ctor; + let arity; let mut fields: Vec<_>; match &pat.kind { PatKind::AscribeUserType { subpattern, .. } @@ -453,9 +454,11 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { PatKind::Binding { subpattern: None, .. } | PatKind::Wild => { ctor = Wildcard; fields = vec![]; + arity = 0; } PatKind::Deref { subpattern } => { fields = vec![self.lower_pat(subpattern)]; + arity = 1; ctor = match ty.kind() { // This is a box pattern. ty::Adt(adt, ..) if adt.is_box() => Struct, @@ -467,6 +470,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { match ty.kind() { ty::Tuple(fs) => { ctor = Struct; + arity = fs.len(); fields = fs .iter() .map(|ty| cx.reveal_opaque_ty(ty)) @@ -497,6 +501,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { }; ctor = Struct; fields = vec![pat]; + arity = 1; } ty::Adt(adt, _) => { ctor = match pat.kind { @@ -507,6 +512,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { }; let variant = &adt.variant(RustcMatchCheckCtxt::variant_index_for_adt(&ctor, *adt)); + arity = variant.fields.len(); fields = cx .variant_sub_tys(ty, variant) .map(|(_, ty)| DeconstructedPat::wildcard(ty)) @@ -526,6 +532,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { None => Opaque(OpaqueId::new()), }; fields = vec![]; + arity = 0; } ty::Char | ty::Int(_) | ty::Uint(_) => { ctor = match value.try_eval_bits(cx.tcx, cx.param_env) { @@ -542,6 +549,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { None => Opaque(OpaqueId::new()), }; fields = vec![]; + arity = 0; } ty::Float(ty::FloatTy::F32) => { ctor = match value.try_eval_bits(cx.tcx, cx.param_env) { @@ -553,6 +561,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { None => Opaque(OpaqueId::new()), }; fields = vec![]; + arity = 0; } ty::Float(ty::FloatTy::F64) => { ctor = match value.try_eval_bits(cx.tcx, cx.param_env) { @@ -564,6 +573,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { None => Opaque(OpaqueId::new()), }; fields = vec![]; + arity = 0; } ty::Ref(_, t, _) if t.is_str() => { // We want a `&str` constant to behave like a `Deref` pattern, to be compatible @@ -574,9 +584,10 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { // subfields. // Note: `t` is `str`, not `&str`. let ty = self.reveal_opaque_ty(*t); - let subpattern = DeconstructedPat::new(Str(*value), Vec::new(), ty, pat); + let subpattern = DeconstructedPat::new(Str(*value), Vec::new(), 0, ty, pat); ctor = Ref; - fields = vec![subpattern] + fields = vec![subpattern]; + arity = 1; } // All constants that can be structurally matched have already been expanded // into the corresponding `Pat`s by `const_to_pat`. Constants that remain are @@ -584,6 +595,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { _ => { ctor = Opaque(OpaqueId::new()); fields = vec![]; + arity = 0; } } } @@ -623,6 +635,7 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { _ => bug!("invalid type for range pattern: {}", ty.inner()), }; fields = vec![]; + arity = 0; } PatKind::Array { prefix, slice, suffix } | PatKind::Slice { prefix, slice, suffix } => { let array_len = match ty.kind() { @@ -639,11 +652,13 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { }; ctor = Slice(Slice::new(array_len, kind)); fields = prefix.iter().chain(suffix.iter()).map(|p| self.lower_pat(&*p)).collect(); + arity = kind.arity(); } PatKind::Or { .. } => { ctor = Or; let pats = expand_or_pat(pat); fields = pats.into_iter().map(|p| self.lower_pat(p)).collect(); + arity = fields.len(); } PatKind::Never => { // A never pattern matches all the values of its type (namely none). Moreover it @@ -651,13 +666,15 @@ impl<'p, 'tcx: 'p> RustcMatchCheckCtxt<'p, 'tcx> { // `Result<!, !>` which has other constructors. Hence we lower it as a wildcard. ctor = Wildcard; fields = vec![]; + arity = 0; } PatKind::Error(_) => { ctor = Opaque(OpaqueId::new()); fields = vec![]; + arity = 0; } } - DeconstructedPat::new(ctor, fields, ty, pat) + DeconstructedPat::new(ctor, fields, arity, ty, pat) } /// Convert back to a `thir::PatRangeBoundary` for diagnostic purposes. |