diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index 398b694ae6bd6..dd8fb1f7eb6c5 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -7,7 +7,7 @@ use rustc_ast::token::CommentKind;
use rustc_ast::util::parser::{AssocOp, ExprPrecedence};
use rustc_ast::{
self as ast, AttrId, AttrStyle, DelimArgs, FloatTy, InlineAsmOptions, InlineAsmTemplatePiece,
- IntTy, Label, LitKind, MetaItemInner, MetaItemLit, TraitObjectSyntax, UintTy,
+ IntTy, Label, LitIntType, LitKind, MetaItemInner, MetaItemLit, TraitObjectSyntax, UintTy,
};
pub use rustc_ast::{
BinOp, BinOpKind, BindingMode, BorrowKind, BoundConstness, BoundPolarity, ByRef, CaptureBy,
@@ -2064,6 +2064,18 @@ impl Expr<'_> {
}
}
+ /// Check if expression is an integer literal that can be used
+ /// where `usize` is expected.
+ pub fn is_size_lit(&self) -> bool {
+ matches!(
+ self.kind,
+ ExprKind::Lit(Lit {
+ node: LitKind::Int(_, LitIntType::Unsuffixed | LitIntType::Unsigned(UintTy::Usize)),
+ ..
+ })
+ )
+ }
+
/// If `Self.kind` is `ExprKind::DropTemps(expr)`, drill down until we get a non-`DropTemps`
/// `Expr`. This is used in suggestions to ignore this `ExprKind` as it is semantically
/// silent, only signaling the ownership system. By doing this, suggestions that check the
diff --git a/compiler/rustc_hir_typeck/messages.ftl b/compiler/rustc_hir_typeck/messages.ftl
index a93da52b2703c..0f424a39840a3 100644
--- a/compiler/rustc_hir_typeck/messages.ftl
+++ b/compiler/rustc_hir_typeck/messages.ftl
@@ -165,6 +165,8 @@ hir_typeck_remove_semi_for_coerce_ret = the `match` arms can conform to this ret
hir_typeck_remove_semi_for_coerce_semi = the `match` is a statement because of this semicolon, consider removing it
hir_typeck_remove_semi_for_coerce_suggestion = remove this semicolon
+hir_typeck_replace_comma_with_semicolon = replace the comma with a semicolon to create {$descr}
+
hir_typeck_return_stmt_outside_of_fn_body =
{$statement_kind} statement outside of function body
.encl_body_label = the {$statement_kind} is part of this body...
diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs
index e51323fc5c852..56f7a2c1150ae 100644
--- a/compiler/rustc_hir_typeck/src/demand.rs
+++ b/compiler/rustc_hir_typeck/src/demand.rs
@@ -30,7 +30,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
if expr_ty == expected {
return;
}
-
self.annotate_alternative_method_deref(err, expr, error);
self.explain_self_literal(err, expr, expected, expr_ty);
@@ -39,6 +38,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
|| self.suggest_missing_unwrap_expect(err, expr, expected, expr_ty)
|| self.suggest_remove_last_method_call(err, expr, expected)
|| self.suggest_associated_const(err, expr, expected)
+ || self.suggest_semicolon_in_repeat_expr(err, expr, expr_ty)
|| self.suggest_deref_ref_or_into(err, expr, expected, expr_ty, expected_ty_expr)
|| self.suggest_option_to_bool(err, expr, expr_ty, expected)
|| self.suggest_compatible_variants(err, expr, expected, expr_ty)
diff --git a/compiler/rustc_hir_typeck/src/errors.rs b/compiler/rustc_hir_typeck/src/errors.rs
index ff09583cc65a6..4eed2bc12388d 100644
--- a/compiler/rustc_hir_typeck/src/errors.rs
+++ b/compiler/rustc_hir_typeck/src/errors.rs
@@ -846,3 +846,16 @@ pub(crate) struct PassFnItemToVariadicFunction {
pub sugg_span: Span,
pub replace: String,
}
+
+#[derive(Subdiagnostic)]
+#[suggestion(
+ hir_typeck_replace_comma_with_semicolon,
+ applicability = "machine-applicable",
+ style = "verbose",
+ code = "; "
+)]
+pub(crate) struct ReplaceCommaWithSemicolon {
+ #[primary_span]
+ pub comma_span: Span,
+ pub descr: &'static str,
+}
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
index 964ef5b2106b1..c17218b611ecb 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
@@ -1319,14 +1319,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
let span = expr.span.shrink_to_hi();
let subdiag = if self.type_is_copy_modulo_regions(self.param_env, ty) {
errors::OptionResultRefMismatch::Copied { span, def_path }
- } else if let Some(clone_did) = self.tcx.lang_items().clone_trait()
- && rustc_trait_selection::traits::type_known_to_meet_bound_modulo_regions(
- self,
- self.param_env,
- ty,
- clone_did,
- )
- {
+ } else if self.type_is_clone_modulo_regions(self.param_env, ty) {
errors::OptionResultRefMismatch::Cloned { span, def_path }
} else {
return false;
@@ -2181,6 +2174,87 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
}
}
+ /// Suggest replacing comma with semicolon in incorrect repeat expressions
+ /// like `["_", 10]` or `vec![String::new(), 10]`.
+ pub(crate) fn suggest_semicolon_in_repeat_expr(
+ &self,
+ err: &mut Diag<'_>,
+ expr: &hir::Expr<'_>,
+ expr_ty: Ty<'tcx>,
+ ) -> bool {
+ // Check if `expr` is contained in array of two elements
+ if let hir::Node::Expr(array_expr) = self.tcx.parent_hir_node(expr.hir_id)
+ && let hir::ExprKind::Array(elements) = array_expr.kind
+ && let [first, second] = &elements[..]
+ && second.hir_id == expr.hir_id
+ {
+ // Span between the two elements of the array
+ let comma_span = first.span.between(second.span);
+
+ // Check if `expr` is a constant value of type `usize`.
+ // This can only detect const variable declarations and
+ // calls to const functions.
+
+ // Checking this here instead of rustc_hir::hir because
+ // this check needs access to `self.tcx` but rustc_hir
+ // has no access to `TyCtxt`.
+ let expr_is_const_usize = expr_ty.is_usize()
+ && match expr.kind {
+ ExprKind::Path(QPath::Resolved(
+ None,
+ Path { res: Res::Def(DefKind::Const, _), .. },
+ )) => true,
+ ExprKind::Call(
+ Expr {
+ kind:
+ ExprKind::Path(QPath::Resolved(
+ None,
+ Path { res: Res::Def(DefKind::Fn, fn_def_id), .. },
+ )),
+ ..
+ },
+ _,
+ ) => self.tcx.is_const_fn(*fn_def_id),
+ _ => false,
+ };
+
+ // Type of the first element is guaranteed to be checked
+ // when execution reaches here because `mismatched types`
+ // error occurs only when type of second element of array
+ // is not the same as type of first element.
+ let first_ty = self.typeck_results.borrow().expr_ty(first);
+
+ // `array_expr` is from a macro `vec!["a", 10]` if
+ // 1. array expression's span is imported from a macro
+ // 2. first element of array implements `Clone` trait
+ // 3. second element is an integer literal or is an expression of `usize` like type
+ if self.tcx.sess.source_map().is_imported(array_expr.span)
+ && self.type_is_clone_modulo_regions(self.param_env, first_ty)
+ && (expr.is_size_lit() || expr_ty.is_usize_like())
+ {
+ err.subdiagnostic(errors::ReplaceCommaWithSemicolon {
+ comma_span,
+ descr: "a vector",
+ });
+ return true;
+ }
+
+ // `array_expr` is from an array `["a", 10]` if
+ // 1. first element of array implements `Copy` trait
+ // 2. second element is an integer literal or is a const value of type `usize`
+ if self.type_is_copy_modulo_regions(self.param_env, first_ty)
+ && (expr.is_size_lit() || expr_is_const_usize)
+ {
+ err.subdiagnostic(errors::ReplaceCommaWithSemicolon {
+ comma_span,
+ descr: "an array",
+ });
+ return true;
+ }
+ }
+ false
+ }
+
/// If the expected type is an enum (Issue #55250) with any variants whose
/// sole field is of the found type, suggest such variants. (Issue #42764)
pub(crate) fn suggest_compatible_variants(
diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs
index 045c483d6a58a..c45238b1eb0e4 100644
--- a/compiler/rustc_middle/src/ty/sty.rs
+++ b/compiler/rustc_middle/src/ty/sty.rs
@@ -27,7 +27,7 @@ use crate::infer::canonical::Canonical;
use crate::ty::InferTy::*;
use crate::ty::{
self, AdtDef, BoundRegionKind, Discr, GenericArg, GenericArgs, GenericArgsRef, List, ParamEnv,
- Region, Ty, TyCtxt, TypeFlags, TypeSuperVisitable, TypeVisitable, TypeVisitor,
+ Region, Ty, TyCtxt, TypeFlags, TypeSuperVisitable, TypeVisitable, TypeVisitor, UintTy,
};
// Re-export and re-parameterize some `I = TyCtxt<'tcx>` types here
@@ -1008,6 +1008,18 @@ impl<'tcx> Ty<'tcx> {
}
}
+ /// Check if type is an `usize`.
+ #[inline]
+ pub fn is_usize(self) -> bool {
+ matches!(self.kind(), Uint(UintTy::Usize))
+ }
+
+ /// Check if type is an `usize` or an integral type variable.
+ #[inline]
+ pub fn is_usize_like(self) -> bool {
+ matches!(self.kind(), Uint(UintTy::Usize) | Infer(IntVar(_)))
+ }
+
#[inline]
pub fn is_never(self) -> bool {
matches!(self.kind(), Never)
diff --git a/compiler/rustc_trait_selection/src/infer.rs b/compiler/rustc_trait_selection/src/infer.rs
index ee708564a8046..f373706b2960c 100644
--- a/compiler/rustc_trait_selection/src/infer.rs
+++ b/compiler/rustc_trait_selection/src/infer.rs
@@ -47,6 +47,12 @@ impl<'tcx> InferCtxt<'tcx> {
traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, copy_def_id)
}
+ fn type_is_clone_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool {
+ let ty = self.resolve_vars_if_possible(ty);
+ let clone_def_id = self.tcx.require_lang_item(LangItem::Clone, None);
+ traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, clone_def_id)
+ }
+
fn type_is_sized_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool {
let lang_item = self.tcx.require_lang_item(LangItem::Sized, None);
traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, lang_item)
diff --git a/tests/ui/repeat-expr/typo-in-repeat-expr-issue-80173.rs b/tests/ui/repeat-expr/typo-in-repeat-expr-issue-80173.rs
new file mode 100644
index 0000000000000..c76e7a1d71665
--- /dev/null
+++ b/tests/ui/repeat-expr/typo-in-repeat-expr-issue-80173.rs
@@ -0,0 +1,70 @@
+#[derive(Copy, Clone)]
+struct Type;
+
+struct NewType;
+
+const fn get_size() -> usize {
+ 10
+}
+
+fn get_dyn_size() -> usize {
+ 10
+}
+
+fn main() {
+ let a = ["a", 10];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create an array
+
+ const size_b: usize = 20;
+ let b = [Type, size_b];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create an array
+
+ let size_c: usize = 13;
+ let c = [Type, size_c];
+ //~^ ERROR mismatched types
+
+ const size_d: bool = true;
+ let d = [Type, size_d];
+ //~^ ERROR mismatched types
+
+ let e = [String::new(), 10];
+ //~^ ERROR mismatched types
+ //~| HELP try using a conversion method
+
+ let f = ["f", get_size()];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create an array
+
+ let m = ["m", get_dyn_size()];
+ //~^ ERROR mismatched types
+
+ // is_vec, is_clone, is_usize_like
+ let g = vec![String::new(), 10];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create a vector
+
+ let dyn_size = 10;
+ let h = vec![Type, dyn_size];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create a vector
+
+ let i = vec![Type, get_dyn_size()];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create a vector
+
+ let k = vec!['c', 10];
+ //~^ ERROR mismatched types
+ //~| HELP replace the comma with a semicolon to create a vector
+
+ let j = vec![Type, 10_u8];
+ //~^ ERROR mismatched types
+
+ let l = vec![NewType, 10];
+ //~^ ERROR mismatched types
+
+ let byte_size: u8 = 10;
+ let h = vec![Type, byte_size];
+ //~^ ERROR mismatched types
+}
diff --git a/tests/ui/repeat-expr/typo-in-repeat-expr-issue-80173.stderr b/tests/ui/repeat-expr/typo-in-repeat-expr-issue-80173.stderr
new file mode 100644
index 0000000000000..95eddbde9e672
--- /dev/null
+++ b/tests/ui/repeat-expr/typo-in-repeat-expr-issue-80173.stderr
@@ -0,0 +1,124 @@
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:15:19
+ |
+LL | let a = ["a", 10];
+ | ^^ expected `&str`, found integer
+ |
+help: replace the comma with a semicolon to create an array
+ |
+LL | let a = ["a"; 10];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:20:20
+ |
+LL | let b = [Type, size_b];
+ | ^^^^^^ expected `Type`, found `usize`
+ |
+help: replace the comma with a semicolon to create an array
+ |
+LL | let b = [Type; size_b];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:25:20
+ |
+LL | let c = [Type, size_c];
+ | ^^^^^^ expected `Type`, found `usize`
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:29:20
+ |
+LL | let d = [Type, size_d];
+ | ^^^^^^ expected `Type`, found `bool`
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:32:29
+ |
+LL | let e = [String::new(), 10];
+ | ^^- help: try using a conversion method: `.to_string()`
+ | |
+ | expected `String`, found integer
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:36:19
+ |
+LL | let f = ["f", get_size()];
+ | ^^^^^^^^^^ expected `&str`, found `usize`
+ |
+help: replace the comma with a semicolon to create an array
+ |
+LL | let f = ["f"; get_size()];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:40:19
+ |
+LL | let m = ["m", get_dyn_size()];
+ | ^^^^^^^^^^^^^^ expected `&str`, found `usize`
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:44:33
+ |
+LL | let g = vec![String::new(), 10];
+ | ^^ expected `String`, found integer
+ |
+help: replace the comma with a semicolon to create a vector
+ |
+LL | let g = vec![String::new(); 10];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:49:24
+ |
+LL | let h = vec![Type, dyn_size];
+ | ^^^^^^^^ expected `Type`, found integer
+ |
+help: replace the comma with a semicolon to create a vector
+ |
+LL | let h = vec![Type; dyn_size];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:53:24
+ |
+LL | let i = vec![Type, get_dyn_size()];
+ | ^^^^^^^^^^^^^^ expected `Type`, found `usize`
+ |
+help: replace the comma with a semicolon to create a vector
+ |
+LL | let i = vec![Type; get_dyn_size()];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:57:23
+ |
+LL | let k = vec!['c', 10];
+ | ^^ expected `char`, found `u8`
+ |
+help: replace the comma with a semicolon to create a vector
+ |
+LL | let k = vec!['c'; 10];
+ | ~
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:61:24
+ |
+LL | let j = vec![Type, 10_u8];
+ | ^^^^^ expected `Type`, found `u8`
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:64:27
+ |
+LL | let l = vec![NewType, 10];
+ | ^^ expected `NewType`, found integer
+
+error[E0308]: mismatched types
+ --> $DIR/typo-in-repeat-expr-issue-80173.rs:68:24
+ |
+LL | let h = vec![Type, byte_size];
+ | ^^^^^^^^^ expected `Type`, found `u8`
+
+error: aborting due to 14 previous errors
+
+For more information about this error, try `rustc --explain E0308`.