diff --git a/compiler/rustc_typeck/src/expr_use_visitor.rs b/compiler/rustc_typeck/src/expr_use_visitor.rs index a8be207dbb3..3d483e322a8 100644 --- a/compiler/rustc_typeck/src/expr_use_visitor.rs +++ b/compiler/rustc_typeck/src/expr_use_visitor.rs @@ -15,7 +15,7 @@ use rustc_index::vec::Idx; use rustc_infer::infer::InferCtxt; use rustc_middle::hir::place::ProjectionKind; use rustc_middle::mir::FakeReadCause; -use rustc_middle::ty::{self, adjustment, Ty, TyCtxt}; +use rustc_middle::ty::{self, adjustment, AdtKind, Ty, TyCtxt}; use rustc_target::abi::VariantIdx; use std::iter; @@ -845,5 +845,20 @@ fn delegate_consume<'a, 'tcx>( } fn is_multivariant_adt(ty: Ty<'tcx>) -> bool { - if let ty::Adt(def, _) = ty.kind() { def.variants.len() > 1 } else { false } + if let ty::Adt(def, _) = ty.kind() { + // Note that if a non-exhaustive SingleVariant is defined in another crate, we need + // to assume that more cases will be added to the variant in the future. This mean + // that we should handle non-exhaustive SingleVariant the same way we would handle + // a MultiVariant. + // If the variant is not local it must be defined in another crate. + let is_non_exhaustive = match def.adt_kind() { + AdtKind::Struct | AdtKind::Union => { + def.non_enum_variant().is_field_list_non_exhaustive() + } + AdtKind::Enum => def.is_variant_list_non_exhaustive(), + }; + def.variants.len() > 1 || (!def.did.is_local() && is_non_exhaustive) + } else { + false + } } diff --git a/src/test/ui/closures/2229_closure_analysis/auxiliary/match_non_exhaustive_lib.rs b/src/test/ui/closures/2229_closure_analysis/auxiliary/match_non_exhaustive_lib.rs new file mode 100644 index 00000000000..4060c409355 --- /dev/null +++ b/src/test/ui/closures/2229_closure_analysis/auxiliary/match_non_exhaustive_lib.rs @@ -0,0 +1,10 @@ +#[non_exhaustive] +pub enum E1 {} + +#[non_exhaustive] +pub enum E2 { A, B } + +#[non_exhaustive] +pub enum E3 { C } + +pub enum E4 { D } diff --git a/src/test/ui/closures/2229_closure_analysis/non-exhaustive-match.rs b/src/test/ui/closures/2229_closure_analysis/non-exhaustive-match.rs new file mode 100644 index 00000000000..318673ef847 --- /dev/null +++ b/src/test/ui/closures/2229_closure_analysis/non-exhaustive-match.rs @@ -0,0 +1,54 @@ +// edition:2021 + +// aux-build:match_non_exhaustive_lib.rs + +/* The error message for non-exhaustive matches on non-local enums + * marked as non-exhaustive should mention the fact that the enum + * is marked as non-exhaustive (issue #85227). + */ + +// Ignore non_exhaustive in the same crate +#[non_exhaustive] +enum L1 { A, B } +enum L2 { C } + +extern crate match_non_exhaustive_lib; +use match_non_exhaustive_lib::{E1, E2, E3, E4}; + +fn foo() -> (L1, L2) {todo!()} +fn bar() -> (E1, E2, E3, E4) {todo!()} + +fn main() { + let (l1, l2) = foo(); + // No error for enums defined in this crate + let _a = || { match l1 { L1::A => (), L1::B => () } }; + // (except if the match is already non-exhaustive) + let _b = || { match l1 { L1::A => () } }; + //~^ ERROR: non-exhaustive patterns: `B` not covered [E0004] + + // l2 should not be captured as it is a non-exhaustive SingleVariant + // defined in this crate + let _c = || { match l2 { L2::C => (), _ => () } }; + let mut mut_l2 = l2; + _c(); + + // E1 is not visibly uninhabited from here + let (e1, e2, e3, e4) = bar(); + let _d = || { match e1 {} }; + //~^ ERROR: non-exhaustive patterns: type `E1` is non-empty [E0004] + let _e = || { match e2 { E2::A => (), E2::B => () } }; + //~^ ERROR: non-exhaustive patterns: `_` not covered [E0004] + let _f = || { match e2 { E2::A => (), E2::B => (), _ => () } }; + + // e3 should be captured as it is a non-exhaustive SingleVariant + // defined in another crate + let _g = || { match e3 { E3::C => (), _ => () } }; + let mut mut_e3 = e3; + //~^ ERROR: cannot move out of `e3` because it is borrowed + _g(); + + // e4 should not be captured as it is a SingleVariant + let _h = || { match e4 { E4::D => (), _ => () } }; + let mut mut_e4 = e4; + _h(); +} diff --git a/src/test/ui/closures/2229_closure_analysis/non-exhaustive-match.stderr b/src/test/ui/closures/2229_closure_analysis/non-exhaustive-match.stderr new file mode 100644 index 00000000000..91ffe1a47f4 --- /dev/null +++ b/src/test/ui/closures/2229_closure_analysis/non-exhaustive-match.stderr @@ -0,0 +1,50 @@ +error[E0004]: non-exhaustive patterns: `B` not covered + --> $DIR/non-exhaustive-match.rs:26:25 + | +LL | enum L1 { A, B } + | ---------------- + | | | + | | not covered + | `L1` defined here +... +LL | let _b = || { match l1 { L1::A => () } }; + | ^^ pattern `B` not covered + | + = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms + = note: the matched value is of type `L1` + +error[E0004]: non-exhaustive patterns: type `E1` is non-empty + --> $DIR/non-exhaustive-match.rs:37:25 + | +LL | let _d = || { match e1 {} }; + | ^^ + | + = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms + = note: the matched value is of type `E1`, which is marked as non-exhaustive + +error[E0004]: non-exhaustive patterns: `_` not covered + --> $DIR/non-exhaustive-match.rs:39:25 + | +LL | let _e = || { match e2 { E2::A => (), E2::B => () } }; + | ^^ pattern `_` not covered + | + = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms + = note: the matched value is of type `E2`, which is marked as non-exhaustive + +error[E0505]: cannot move out of `e3` because it is borrowed + --> $DIR/non-exhaustive-match.rs:46:22 + | +LL | let _g = || { match e3 { E3::C => (), _ => () } }; + | -- -- borrow occurs due to use in closure + | | + | borrow of `e3` occurs here +LL | let mut mut_e3 = e3; + | ^^ move out of `e3` occurs here +LL | +LL | _g(); + | -- borrow later used here + +error: aborting due to 4 previous errors + +Some errors have detailed explanations: E0004, E0505. +For more information about an error, try `rustc --explain E0004`.