diff --git a/compiler/rustc_hir_typeck/src/pat.rs b/compiler/rustc_hir_typeck/src/pat.rs index 11ff65d0c37..0160bce8604 100644 --- a/compiler/rustc_hir_typeck/src/pat.rs +++ b/compiler/rustc_hir_typeck/src/pat.rs @@ -36,6 +36,10 @@ You can read more about trait objects in the Trait Objects section of the Reference: \ https://doc.rust-lang.org/reference/types.html#trait-objects"; +fn is_number(text: &str) -> bool { + text.chars().all(|c: char| c.is_digit(10)) +} + /// Information about the expected type at the top level of type checking a pattern. /// /// **NOTE:** This is only for use by diagnostics. Do NOT use for type checking logic! @@ -1671,7 +1675,15 @@ fn error_tuple_variant_as_struct_pat( fields: &'tcx [hir::PatField<'tcx>], variant: &ty::VariantDef, ) -> Option> { - if let (Some(CtorKind::Fn), PatKind::Struct(qpath, ..)) = (variant.ctor_kind(), &pat.kind) { + if let (Some(CtorKind::Fn), PatKind::Struct(qpath, pattern_fields, ..)) = + (variant.ctor_kind(), &pat.kind) + { + let is_tuple_struct_match = !pattern_fields.is_empty() + && pattern_fields.iter().map(|field| field.ident.name.as_str()).all(is_number); + if is_tuple_struct_match { + return None; + } + let path = rustc_hir_pretty::to_string(rustc_hir_pretty::NO_ANN, |s| { s.print_qpath(qpath, false) }); @@ -1893,7 +1905,14 @@ fn error_unmentioned_fields( prefix, unmentioned_fields .iter() - .map(|(_, name)| name.to_string()) + .map(|(_, name)| { + let field_name = name.to_string(); + if is_number(&field_name) { + format!("{}: _", field_name) + } else { + field_name + } + }) .collect::>() .join(", "), if have_inaccessible_fields { ", .." } else { "" }, diff --git a/tests/ui/structs/struct-tuple-field-names.rs b/tests/ui/structs/struct-tuple-field-names.rs index 7bd54af1dbe..33f264aa250 100644 --- a/tests/ui/structs/struct-tuple-field-names.rs +++ b/tests/ui/structs/struct-tuple-field-names.rs @@ -12,4 +12,7 @@ fn main() { match y { S { } => {} //~ ERROR: tuple variant `S` written as struct variant [E0769] } + + if let E::S { 0: a } = x { //~ ERROR: pattern does not mention field `1` + } } diff --git a/tests/ui/structs/struct-tuple-field-names.stderr b/tests/ui/structs/struct-tuple-field-names.stderr index 5494c29a6fd..0b837a47a82 100644 --- a/tests/ui/structs/struct-tuple-field-names.stderr +++ b/tests/ui/structs/struct-tuple-field-names.stderr @@ -20,6 +20,22 @@ help: use the tuple variant pattern syntax instead LL | S(_, _) => {} | ~~~~~~ -error: aborting due to 2 previous errors +error[E0027]: pattern does not mention field `1` + --> $DIR/struct-tuple-field-names.rs:16:12 + | +LL | if let E::S { 0: a } = x { + | ^^^^^^^^^^^^^ missing field `1` + | +help: include the missing field in the pattern + | +LL | if let E::S { 0: a, 1: _ } = x { + | ~~~~~~~~ +help: if you don't care about this missing field, you can explicitly ignore it + | +LL | if let E::S { 0: a, .. } = x { + | ~~~~~~ -For more information about this error, try `rustc --explain E0769`. +error: aborting due to 3 previous errors + +Some errors have detailed explanations: E0027, E0769. +For more information about an error, try `rustc --explain E0027`.