From de84ad95b4b097e504171c7c606bf3715803c13b Mon Sep 17 00:00:00 2001
From: Fabian Zaiser <fabian.zaiser@gmail.com>
Date: Sat, 7 Nov 2020 14:28:55 +0000
Subject: [PATCH] Implement destructuring assignment for structs and slices
Co-authored-by: varkor <github@varkor.com>
---
compiler/rustc_ast/src/ast.rs | 19 ++-
compiler/rustc_ast/src/mut_visit.rs | 6 +-
compiler/rustc_ast/src/visit.rs | 6 +-
compiler/rustc_ast_lowering/src/expr.rs | 126 +++++++++++++++++-
compiler/rustc_ast_passes/src/feature_gate.rs | 1 +
compiler/rustc_ast_pretty/src/pprust/state.rs | 21 ++-
compiler/rustc_expand/src/build.rs | 2 +-
compiler/rustc_hir/src/def.rs | 5 +
compiler/rustc_parse/src/parser/expr.rs | 10 +-
compiler/rustc_resolve/src/late.rs | 4 +-
.../rustc_save_analysis/src/dump_visitor.rs | 10 +-
src/test/ui-fulldeps/pprust-expr-roundtrip.rs | 2 +-
.../nested_destructure.rs | 17 +++
.../note-unsupported.rs | 7 +-
.../note-unsupported.stderr | 69 ++++++----
.../slice_destructure.rs | 15 +++
.../slice_destructure_fail.rs | 7 +
.../slice_destructure_fail.stderr | 17 +++
.../struct_destructure.rs | 19 +++
.../struct_destructure_fail.rs | 15 +++
.../struct_destructure_fail.stderr | 21 +++
.../tuple_struct_destructure.rs | 34 +++++
.../tuple_struct_destructure_fail.rs | 42 ++++++
.../tuple_struct_destructure_fail.stderr | 62 +++++++++
.../underscore-range-expr-gating.rs | 8 ++
.../underscore-range-expr-gating.stderr | 12 ++
src/test/ui/issues/issue-77218.rs | 10 +-
src/test/ui/issues/issue-77218.stderr | 38 +++++-
src/test/ui/suggestions/if-let-typo.rs | 5 +
src/test/ui/suggestions/if-let-typo.stderr | 75 +++++++----
.../clippy_lints/src/utils/ast_utils.rs | 11 +-
.../clippy/tests/ui/crashes/ice-6250.stderr | 29 +++-
32 files changed, 618 insertions(+), 107 deletions(-)
create mode 100644 src/test/ui/destructuring-assignment/nested_destructure.rs
create mode 100644 src/test/ui/destructuring-assignment/slice_destructure.rs
create mode 100644 src/test/ui/destructuring-assignment/slice_destructure_fail.rs
create mode 100644 src/test/ui/destructuring-assignment/slice_destructure_fail.stderr
create mode 100644 src/test/ui/destructuring-assignment/struct_destructure.rs
create mode 100644 src/test/ui/destructuring-assignment/struct_destructure_fail.rs
create mode 100644 src/test/ui/destructuring-assignment/struct_destructure_fail.stderr
create mode 100644 src/test/ui/destructuring-assignment/tuple_struct_destructure.rs
create mode 100644 src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.rs
create mode 100644 src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.stderr
create mode 100644 src/test/ui/destructuring-assignment/underscore-range-expr-gating.rs
create mode 100644 src/test/ui/destructuring-assignment/underscore-range-expr-gating.stderr
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index f13d67b9c1584..1886581df9a94 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -1061,7 +1061,7 @@ pub struct Expr {
// `Expr` is used a lot. Make sure it doesn't unintentionally get bigger.
#[cfg(target_arch = "x86_64")]
-rustc_data_structures::static_assert_size!(Expr, 112);
+rustc_data_structures::static_assert_size!(Expr, 120);
impl Expr {
/// Returns `true` if this expression would be valid somewhere that expects a value;
@@ -1218,6 +1218,16 @@ pub enum RangeLimits {
Closed,
}
+#[derive(Clone, Encodable, Decodable, Debug)]
+pub enum StructRest {
+ /// `..x`.
+ Base(P<Expr>),
+ /// `..`.
+ Rest(Span),
+ /// No trailing `..` or expression.
+ None,
+}
+
#[derive(Clone, Encodable, Decodable, Debug)]
pub enum ExprKind {
/// A `box x` expression.
@@ -1312,7 +1322,7 @@ pub enum ExprKind {
Field(P<Expr>, Ident),
/// An indexing operation (e.g., `foo[2]`).
Index(P<Expr>, P<Expr>),
- /// A range (e.g., `1..2`, `1..`, `..2`, `1..=2`, `..=2`).
+ /// A range (e.g., `1..2`, `1..`, `..2`, `1..=2`, `..=2`; and `..` in destructuring assingment).
Range(Option<P<Expr>>, Option<P<Expr>>, RangeLimits),
/// Variable reference, possibly containing `::` and/or type
@@ -1340,9 +1350,8 @@ pub enum ExprKind {
/// A struct literal expression.
///
- /// E.g., `Foo {x: 1, y: 2}`, or `Foo {x: 1, .. base}`,
- /// where `base` is the `Option<Expr>`.
- Struct(Path, Vec<Field>, Option<P<Expr>>),
+ /// E.g., `Foo {x: 1, y: 2}`, or `Foo {x: 1, .. rest}`.
+ Struct(Path, Vec<Field>, StructRest),
/// An array literal constructed from one repeated element.
///
diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs
index 7b85d28568bd3..a80a6adb4fae8 100644
--- a/compiler/rustc_ast/src/mut_visit.rs
+++ b/compiler/rustc_ast/src/mut_visit.rs
@@ -1288,7 +1288,11 @@ pub fn noop_visit_expr<T: MutVisitor>(
ExprKind::Struct(path, fields, expr) => {
vis.visit_path(path);
fields.flat_map_in_place(|field| vis.flat_map_field(field));
- visit_opt(expr, |expr| vis.visit_expr(expr));
+ match expr {
+ StructRest::Base(expr) => vis.visit_expr(expr),
+ StructRest::Rest(_span) => {}
+ StructRest::None => {}
+ }
}
ExprKind::Paren(expr) => {
vis.visit_expr(expr);
diff --git a/compiler/rustc_ast/src/visit.rs b/compiler/rustc_ast/src/visit.rs
index 8751f09cfcbbe..0666eb199e673 100644
--- a/compiler/rustc_ast/src/visit.rs
+++ b/compiler/rustc_ast/src/visit.rs
@@ -719,7 +719,11 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
ExprKind::Struct(ref path, ref fields, ref optional_base) => {
visitor.visit_path(path, expression.id);
walk_list!(visitor, visit_field, fields);
- walk_list!(visitor, visit_expr, optional_base);
+ match optional_base {
+ StructRest::Base(expr) => visitor.visit_expr(expr),
+ StructRest::Rest(_span) => {}
+ StructRest::None => {}
+ }
}
ExprKind::Tup(ref subexpressions) => {
walk_list!(visitor, visit_expr, subexpressions);
diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs
index 1f2aba2b27e68..330776fc8c598 100644
--- a/compiler/rustc_ast_lowering/src/expr.rs
+++ b/compiler/rustc_ast_lowering/src/expr.rs
@@ -187,8 +187,18 @@ impl<'hir> LoweringContext<'_, 'hir> {
}
ExprKind::InlineAsm(ref asm) => self.lower_expr_asm(e.span, asm),
ExprKind::LlvmInlineAsm(ref asm) => self.lower_expr_llvm_asm(asm),
- ExprKind::Struct(ref path, ref fields, ref maybe_expr) => {
- let maybe_expr = maybe_expr.as_ref().map(|x| self.lower_expr(x));
+ ExprKind::Struct(ref path, ref fields, ref rest) => {
+ let rest = match rest {
+ StructRest::Base(e) => Some(self.lower_expr(e)),
+ StructRest::Rest(sp) => {
+ self.sess
+ .struct_span_err(*sp, "base expression required after `..`")
+ .span_label(*sp, "add a base expression here")
+ .emit();
+ Some(&*self.arena.alloc(self.expr_err(*sp)))
+ }
+ StructRest::None => None,
+ };
hir::ExprKind::Struct(
self.arena.alloc(self.lower_qpath(
e.id,
@@ -198,7 +208,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
ImplTraitContext::disallowed(),
)),
self.arena.alloc_from_iter(fields.iter().map(|x| self.lower_field(x))),
- maybe_expr,
+ rest,
)
}
ExprKind::Yield(ref opt_expr) => self.lower_expr_yield(e.span, opt_expr.as_deref()),
@@ -851,20 +861,22 @@ impl<'hir> LoweringContext<'_, 'hir> {
whole_span: Span,
) -> hir::ExprKind<'hir> {
// Return early in case of an ordinary assignment.
- fn is_ordinary(lhs: &Expr) -> bool {
+ fn is_ordinary(lower_ctx: &mut LoweringContext<'_, '_>, lhs: &Expr) -> bool {
match &lhs.kind {
- ExprKind::Tup(..) => false,
+ ExprKind::Array(..) | ExprKind::Struct(..) | ExprKind::Tup(..) => false,
+ // Check for tuple struct constructor.
+ ExprKind::Call(callee, ..) => lower_ctx.extract_tuple_struct_path(callee).is_none(),
ExprKind::Paren(e) => {
match e.kind {
// We special-case `(..)` for consistency with patterns.
ExprKind::Range(None, None, RangeLimits::HalfOpen) => false,
- _ => is_ordinary(e),
+ _ => is_ordinary(lower_ctx, e),
}
}
_ => true,
}
}
- if is_ordinary(lhs) {
+ if is_ordinary(self, lhs) {
return hir::ExprKind::Assign(self.lower_expr(lhs), self.lower_expr(rhs), eq_sign_span);
}
if !self.sess.features_untracked().destructuring_assignment {
@@ -902,6 +914,26 @@ impl<'hir> LoweringContext<'_, 'hir> {
hir::ExprKind::Block(&self.block_all(whole_span, stmts, None), None)
}
+ /// If the given expression is a path to a tuple struct, returns that path.
+ /// It is not a complete check, but just tries to reject most paths early
+ /// if they are not tuple structs.
+ /// Type checking will take care of the full validation later.
+ fn extract_tuple_struct_path<'a>(&mut self, expr: &'a Expr) -> Option<&'a Path> {
+ // For tuple struct destructuring, it must be a non-qualified path (like in patterns).
+ if let ExprKind::Path(None, path) = &expr.kind {
+ // Does the path resolves to something disallowed in a tuple struct/variant pattern?
+ if let Some(partial_res) = self.resolver.get_partial_res(expr.id) {
+ if partial_res.unresolved_segments() == 0
+ && !partial_res.base_res().expected_in_tuple_struct_pat()
+ {
+ return None;
+ }
+ }
+ return Some(path);
+ }
+ None
+ }
+
/// Convert the LHS of a destructuring assignment to a pattern.
/// Each sub-assignment is recorded in `assignments`.
fn destructure_assign(
@@ -911,6 +943,86 @@ impl<'hir> LoweringContext<'_, 'hir> {
assignments: &mut Vec<hir::Stmt<'hir>>,
) -> &'hir hir::Pat<'hir> {
match &lhs.kind {
+ // Slice patterns.
+ ExprKind::Array(elements) => {
+ let (pats, rest) =
+ self.destructure_sequence(elements, "slice", eq_sign_span, assignments);
+ let slice_pat = if let Some((i, span)) = rest {
+ let (before, after) = pats.split_at(i);
+ hir::PatKind::Slice(
+ before,
+ Some(self.pat_without_dbm(span, hir::PatKind::Wild)),
+ after,
+ )
+ } else {
+ hir::PatKind::Slice(pats, None, &[])
+ };
+ return self.pat_without_dbm(lhs.span, slice_pat);
+ }
+ // Tuple structs.
+ ExprKind::Call(callee, args) => {
+ if let Some(path) = self.extract_tuple_struct_path(callee) {
+ let (pats, rest) = self.destructure_sequence(
+ args,
+ "tuple struct or variant",
+ eq_sign_span,
+ assignments,
+ );
+ let qpath = self.lower_qpath(
+ callee.id,
+ &None,
+ path,
+ ParamMode::Optional,
+ ImplTraitContext::disallowed(),
+ );
+ // Destructure like a tuple struct.
+ let tuple_struct_pat =
+ hir::PatKind::TupleStruct(qpath, pats, rest.map(|r| r.0));
+ return self.pat_without_dbm(lhs.span, tuple_struct_pat);
+ }
+ }
+ // Structs.
+ ExprKind::Struct(path, fields, rest) => {
+ let field_pats = self.arena.alloc_from_iter(fields.iter().map(|f| {
+ let pat = self.destructure_assign(&f.expr, eq_sign_span, assignments);
+ hir::FieldPat {
+ hir_id: self.next_id(),
+ ident: f.ident,
+ pat,
+ is_shorthand: f.is_shorthand,
+ span: f.span,
+ }
+ }));
+ let qpath = self.lower_qpath(
+ lhs.id,
+ &None,
+ path,
+ ParamMode::Optional,
+ ImplTraitContext::disallowed(),
+ );
+ let fields_omitted = match rest {
+ StructRest::Base(e) => {
+ self.sess
+ .struct_span_err(
+ e.span,
+ "functional record updates are not allowed in destructuring \
+ assignments",
+ )
+ .span_suggestion(
+ e.span,
+ "consider removing the trailing pattern",
+ String::new(),
+ rustc_errors::Applicability::MachineApplicable,
+ )
+ .emit();
+ true
+ }
+ StructRest::Rest(_) => true,
+ StructRest::None => false,
+ };
+ let struct_pat = hir::PatKind::Struct(qpath, field_pats, fields_omitted);
+ return self.pat_without_dbm(lhs.span, struct_pat);
+ }
// Tuples.
ExprKind::Tup(elements) => {
let (pats, rest) =
diff --git a/compiler/rustc_ast_passes/src/feature_gate.rs b/compiler/rustc_ast_passes/src/feature_gate.rs
index f20084497671f..2831675cb3671 100644
--- a/compiler/rustc_ast_passes/src/feature_gate.rs
+++ b/compiler/rustc_ast_passes/src/feature_gate.rs
@@ -630,6 +630,7 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session) {
gate_all!(const_trait_impl, "const trait impls are experimental");
gate_all!(half_open_range_patterns, "half-open range patterns are unstable");
gate_all!(inline_const, "inline-const is experimental");
+ gate_all!(destructuring_assignment, "destructuring assignments are unstable");
// All uses of `gate_all!` below this point were added in #65742,
// and subsequently disabled (with the non-early gating readded).
diff --git a/compiler/rustc_ast_pretty/src/pprust/state.rs b/compiler/rustc_ast_pretty/src/pprust/state.rs
index 9fcba90244330..17b3711b485ea 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state.rs
@@ -1729,7 +1729,7 @@ impl<'a> State<'a> {
&mut self,
path: &ast::Path,
fields: &[ast::Field],
- wth: &Option<P<ast::Expr>>,
+ rest: &ast::StructRest,
attrs: &[ast::Attribute],
) {
self.print_path(path, true, 0);
@@ -1750,22 +1750,21 @@ impl<'a> State<'a> {
},
|f| f.span,
);
- match *wth {
- Some(ref expr) => {
+ match rest {
+ ast::StructRest::Base(_) | ast::StructRest::Rest(_) => {
self.ibox(INDENT_UNIT);
if !fields.is_empty() {
self.s.word(",");
self.s.space();
}
self.s.word("..");
- self.print_expr(expr);
- self.end();
- }
- _ => {
- if !fields.is_empty() {
- self.s.word(",")
+ if let ast::StructRest::Base(ref expr) = *rest {
+ self.print_expr(expr);
}
+ self.end();
}
+ ast::StructRest::None if !fields.is_empty() => self.s.word(","),
+ _ => {}
}
self.s.word("}");
}
@@ -1891,8 +1890,8 @@ impl<'a> State<'a> {
ast::ExprKind::Repeat(ref element, ref count) => {
self.print_expr_repeat(element, count, attrs);
}
- ast::ExprKind::Struct(ref path, ref fields, ref wth) => {
- self.print_expr_struct(path, &fields[..], wth, attrs);
+ ast::ExprKind::Struct(ref path, ref fields, ref rest) => {
+ self.print_expr_struct(path, &fields[..], rest, attrs);
}
ast::ExprKind::Tup(ref exprs) => {
self.print_expr_tup(&exprs[..], attrs);
diff --git a/compiler/rustc_expand/src/build.rs b/compiler/rustc_expand/src/build.rs
index 1c9bfb902d61a..30f0fc6cddfa2 100644
--- a/compiler/rustc_expand/src/build.rs
+++ b/compiler/rustc_expand/src/build.rs
@@ -298,7 +298,7 @@ impl<'a> ExtCtxt<'a> {
path: ast::Path,
fields: Vec<ast::Field>,
) -> P<ast::Expr> {
- self.expr(span, ast::ExprKind::Struct(path, fields, None))
+ self.expr(span, ast::ExprKind::Struct(path, fields, ast::StructRest::None))
}
pub fn expr_struct_ident(
&self,
diff --git a/compiler/rustc_hir/src/def.rs b/compiler/rustc_hir/src/def.rs
index 193247af584bb..298cfcc254c86 100644
--- a/compiler/rustc_hir/src/def.rs
+++ b/compiler/rustc_hir/src/def.rs
@@ -484,4 +484,9 @@ impl<Id> Res<Id> {
pub fn matches_ns(&self, ns: Namespace) -> bool {
self.ns().map_or(true, |actual_ns| actual_ns == ns)
}
+
+ /// Returns whether such a resolved path can occur in a tuple struct/variant pattern
+ pub fn expected_in_tuple_struct_pat(&self) -> bool {
+ matches!(self, Res::Def(DefKind::Ctor(_, CtorKind::Fn), _) | Res::SelfCtor(..))
+ }
}
diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs
index c2a13d4b0dec1..188bf227c4249 100644
--- a/compiler/rustc_parse/src/parser/expr.rs
+++ b/compiler/rustc_parse/src/parser/expr.rs
@@ -2087,7 +2087,7 @@ impl<'a> Parser<'a> {
recover: bool,
) -> PResult<'a, P<Expr>> {
let mut fields = Vec::new();
- let mut base = None;
+ let mut base = ast::StructRest::None;
let mut recover_async = false;
attrs.extend(self.parse_inner_attributes()?);
@@ -2102,8 +2102,14 @@ impl<'a> Parser<'a> {
while self.token != token::CloseDelim(token::Brace) {
if self.eat(&token::DotDot) {
let exp_span = self.prev_token.span;
+ // We permit `.. }` on the left-hand side of a destructuring assignment.
+ if self.check(&token::CloseDelim(token::Brace)) {
+ self.sess.gated_spans.gate(sym::destructuring_assignment, self.prev_token.span);
+ base = ast::StructRest::Rest(self.prev_token.span.shrink_to_hi());
+ break;
+ }
match self.parse_expr() {
- Ok(e) => base = Some(e),
+ Ok(e) => base = ast::StructRest::Base(e),
Err(mut e) if recover => {
e.emit();
self.recover_stmt();
diff --git a/compiler/rustc_resolve/src/late.rs b/compiler/rustc_resolve/src/late.rs
index 2337f0d09abb7..2149fd7e01184 100644
--- a/compiler/rustc_resolve/src/late.rs
+++ b/compiler/rustc_resolve/src/late.rs
@@ -298,9 +298,7 @@ impl<'a> PathSource<'a> {
_,
)
| Res::SelfCtor(..)),
- PathSource::TupleStruct(..) => {
- matches!(res, Res::Def(DefKind::Ctor(_, CtorKind::Fn), _) | Res::SelfCtor(..))
- }
+ PathSource::TupleStruct(..) => res.expected_in_tuple_struct_pat(),
PathSource::Struct => matches!(res, Res::Def(
DefKind::Struct
| DefKind::Union
diff --git a/compiler/rustc_save_analysis/src/dump_visitor.rs b/compiler/rustc_save_analysis/src/dump_visitor.rs
index dbb5e3cc9f066..40d60a8394be3 100644
--- a/compiler/rustc_save_analysis/src/dump_visitor.rs
+++ b/compiler/rustc_save_analysis/src/dump_visitor.rs
@@ -816,7 +816,7 @@ impl<'tcx> DumpVisitor<'tcx> {
path: &'tcx hir::QPath<'tcx>,
fields: &'tcx [hir::Field<'tcx>],
variant: &'tcx ty::VariantDef,
- base: Option<&'tcx hir::Expr<'tcx>>,
+ rest: Option<&'tcx hir::Expr<'tcx>>,
) {
if let Some(struct_lit_data) = self.save_ctxt.get_expr_data(ex) {
if let hir::QPath::Resolved(_, path) = path {
@@ -836,7 +836,9 @@ impl<'tcx> DumpVisitor<'tcx> {
}
}
- walk_list!(self, visit_expr, base);
+ if let Some(base) = rest {
+ self.visit_expr(&base);
+ }
}
fn process_method_call(
@@ -1399,7 +1401,7 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
debug!("visit_expr {:?}", ex.kind);
self.process_macro_use(ex.span);
match ex.kind {
- hir::ExprKind::Struct(ref path, ref fields, ref base) => {
+ hir::ExprKind::Struct(ref path, ref fields, ref rest) => {
let hir_expr = self.save_ctxt.tcx.hir().expect_expr(ex.hir_id);
let adt = match self.save_ctxt.typeck_results().expr_ty_opt(&hir_expr) {
Some(ty) if ty.ty_adt_def().is_some() => ty.ty_adt_def().unwrap(),
@@ -1409,7 +1411,7 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
}
};
let res = self.save_ctxt.get_path_res(hir_expr.hir_id);
- self.process_struct_lit(ex, path, fields, adt.variant_of_res(res), *base)
+ self.process_struct_lit(ex, path, fields, adt.variant_of_res(res), *rest)
}
hir::ExprKind::MethodCall(ref seg, _, args, _) => {
self.process_method_call(ex, seg, args)
diff --git a/src/test/ui-fulldeps/pprust-expr-roundtrip.rs b/src/test/ui-fulldeps/pprust-expr-roundtrip.rs
index caf55bec53ddd..bff92d8607ece 100644
--- a/src/test/ui-fulldeps/pprust-expr-roundtrip.rs
+++ b/src/test/ui-fulldeps/pprust-expr-roundtrip.rs
@@ -155,7 +155,7 @@ fn iter_exprs(depth: usize, f: &mut dyn FnMut(P<Expr>)) {
},
17 => {
let path = Path::from_ident(Ident::from_str("S"));
- g(ExprKind::Struct(path, vec![], Some(make_x())));
+ g(ExprKind::Struct(path, vec![], StructRest::Base(make_x())));
},
18 => {
iter_exprs(depth - 1, &mut |e| g(ExprKind::Try(e)));
diff --git a/src/test/ui/destructuring-assignment/nested_destructure.rs b/src/test/ui/destructuring-assignment/nested_destructure.rs
new file mode 100644
index 0000000000000..393dfc16c0a1c
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/nested_destructure.rs
@@ -0,0 +1,17 @@
+// run-pass
+
+#![feature(destructuring_assignment)]
+
+struct Struct<S, T> {
+ a: S,
+ b: T,
+}
+
+struct TupleStruct<S, T>(S, T);
+
+fn main() {
+ let (a, b, c, d);
+ Struct { a: TupleStruct((a, b), c), b: [d] } =
+ Struct { a: TupleStruct((0, 1), 2), b: [3] };
+ assert_eq!((a, b, c, d), (0, 1, 2, 3));
+}
diff --git a/src/test/ui/destructuring-assignment/note-unsupported.rs b/src/test/ui/destructuring-assignment/note-unsupported.rs
index e0cb9dc9158e2..249fba7f920bc 100644
--- a/src/test/ui/destructuring-assignment/note-unsupported.rs
+++ b/src/test/ui/destructuring-assignment/note-unsupported.rs
@@ -7,18 +7,19 @@ fn main() {
(a, b) += (3, 4); //~ ERROR invalid left-hand side of assignment
//~| ERROR binary assignment operation `+=` cannot be applied
- [a, b] = [3, 4]; //~ ERROR invalid left-hand side of assignment
+ [a, b] = [3, 4]; //~ ERROR destructuring assignments are unstable
[a, b] += [3, 4]; //~ ERROR invalid left-hand side of assignment
//~| ERROR binary assignment operation `+=` cannot be applied
let s = S { x: 3, y: 4 };
- S { x: a, y: b } = s; //~ ERROR invalid left-hand side of assignment
+ S { x: a, y: b } = s; //~ ERROR destructuring assignments are unstable
S { x: a, y: b } += s; //~ ERROR invalid left-hand side of assignment
//~| ERROR binary assignment operation `+=` cannot be applied
S { x: a, ..s } = S { x: 3, y: 4 };
- //~^ ERROR invalid left-hand side of assignment
+ //~^ ERROR functional record updates are not allowed in destructuring assignments
+ //~| ERROR destructuring assignments are unstable
let c = 3;
diff --git a/src/test/ui/destructuring-assignment/note-unsupported.stderr b/src/test/ui/destructuring-assignment/note-unsupported.stderr
index c5543fab825eb..a81324b99e586 100644
--- a/src/test/ui/destructuring-assignment/note-unsupported.stderr
+++ b/src/test/ui/destructuring-assignment/note-unsupported.stderr
@@ -10,7 +10,46 @@ LL | (a, b) = (3, 4);
= help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
error[E0658]: destructuring assignments are unstable
- --> $DIR/note-unsupported.rs:25:17
+ --> $DIR/note-unsupported.rs:10:12
+ |
+LL | [a, b] = [3, 4];
+ | ------ ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/note-unsupported.rs:16:22
+ |
+LL | S { x: a, y: b } = s;
+ | ---------------- ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/note-unsupported.rs:20:21
+ |
+LL | S { x: a, ..s } = S { x: 3, y: 4 };
+ | --------------- ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error: functional record updates are not allowed in destructuring assignments
+ --> $DIR/note-unsupported.rs:20:17
+ |
+LL | S { x: a, ..s } = S { x: 3, y: 4 };
+ | ^ help: consider removing the trailing pattern
+
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/note-unsupported.rs:26:17
|
LL | ((a, b), c) = ((3, 4), 5);
| ----------- ^
@@ -36,14 +75,6 @@ LL | (a, b) += (3, 4);
| |
| cannot assign to this expression
-error[E0070]: invalid left-hand side of assignment
- --> $DIR/note-unsupported.rs:10:12
- |
-LL | [a, b] = [3, 4];
- | ------ ^
- | |
- | cannot assign to this expression
-
error[E0368]: binary assignment operation `+=` cannot be applied to type `[{integer}; 2]`
--> $DIR/note-unsupported.rs:11:5
|
@@ -60,14 +91,6 @@ LL | [a, b] += [3, 4];
| |
| cannot assign to this expression
-error[E0070]: invalid left-hand side of assignment
- --> $DIR/note-unsupported.rs:16:22
- |
-LL | S { x: a, y: b } = s;
- | ---------------- ^
- | |
- | cannot assign to this expression
-
error[E0368]: binary assignment operation `+=` cannot be applied to type `S`
--> $DIR/note-unsupported.rs:17:5
|
@@ -86,15 +109,7 @@ LL | S { x: a, y: b } += s;
| |
| cannot assign to this expression
-error[E0070]: invalid left-hand side of assignment
- --> $DIR/note-unsupported.rs:20:21
- |
-LL | S { x: a, ..s } = S { x: 3, y: 4 };
- | --------------- ^
- | |
- | cannot assign to this expression
-
-error: aborting due to 11 previous errors
+error: aborting due to 12 previous errors
-Some errors have detailed explanations: E0067, E0070, E0368, E0658.
+Some errors have detailed explanations: E0067, E0368, E0658.
For more information about an error, try `rustc --explain E0067`.
diff --git a/src/test/ui/destructuring-assignment/slice_destructure.rs b/src/test/ui/destructuring-assignment/slice_destructure.rs
new file mode 100644
index 0000000000000..3dd10aff19c72
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/slice_destructure.rs
@@ -0,0 +1,15 @@
+// run-pass
+
+#![feature(destructuring_assignment)]
+
+fn main() {
+ let (mut a, mut b);
+ [a, b] = [0, 1];
+ assert_eq!((a, b), (0, 1));
+ let mut c;
+ [a, .., b, c] = [1, 2, 3, 4, 5];
+ assert_eq!((a, b, c), (1, 4, 5));
+ [..] = [1, 2, 3];
+ [c, ..] = [5, 6, 6];
+ assert_eq!(c, 5);
+}
diff --git a/src/test/ui/destructuring-assignment/slice_destructure_fail.rs b/src/test/ui/destructuring-assignment/slice_destructure_fail.rs
new file mode 100644
index 0000000000000..f636ea3511c26
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/slice_destructure_fail.rs
@@ -0,0 +1,7 @@
+#![feature(destructuring_assignment)]
+
+fn main() {
+ let (mut a, mut b);
+ [a, .., b, ..] = [0, 1]; //~ ERROR `..` can only be used once per slice pattern
+ [a, a, b] = [1, 2]; //~ ERROR pattern requires 3 elements but array has 2
+}
diff --git a/src/test/ui/destructuring-assignment/slice_destructure_fail.stderr b/src/test/ui/destructuring-assignment/slice_destructure_fail.stderr
new file mode 100644
index 0000000000000..728687deb8bbb
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/slice_destructure_fail.stderr
@@ -0,0 +1,17 @@
+error: `..` can only be used once per slice pattern
+ --> $DIR/slice_destructure_fail.rs:5:14
+ |
+LL | [a, .., b, ..] = [0, 1];
+ | -- ^^ can only be used once per slice pattern
+ | |
+ | previously used here
+
+error[E0527]: pattern requires 3 elements but array has 2
+ --> $DIR/slice_destructure_fail.rs:6:3
+ |
+LL | [a, a, b] = [1, 2];
+ | ^^^^^^^^^ expected 2 elements
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0527`.
diff --git a/src/test/ui/destructuring-assignment/struct_destructure.rs b/src/test/ui/destructuring-assignment/struct_destructure.rs
new file mode 100644
index 0000000000000..b3a96ee157346
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/struct_destructure.rs
@@ -0,0 +1,19 @@
+// run-pass
+
+#![feature(destructuring_assignment)]
+struct Struct<S, T> {
+ a: S,
+ b: T,
+}
+
+fn main() {
+ let (mut a, mut b);
+ Struct { a, b } = Struct { a: 0, b: 1 };
+ assert_eq!((a, b), (0, 1));
+ Struct { a: b, b: a } = Struct { a: 1, b: 2 };
+ assert_eq!((a,b), (2, 1));
+ Struct { a, .. } = Struct { a: 1, b: 3 };
+ assert_eq!((a, b), (1, 1));
+ Struct { .. } = Struct { a: 1, b: 4 };
+ assert_eq!((a, b), (1, 1));
+}
diff --git a/src/test/ui/destructuring-assignment/struct_destructure_fail.rs b/src/test/ui/destructuring-assignment/struct_destructure_fail.rs
new file mode 100644
index 0000000000000..c22695ed38849
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/struct_destructure_fail.rs
@@ -0,0 +1,15 @@
+#![feature(destructuring_assignment)]
+struct Struct<S, T> {
+ a: S,
+ b: T,
+}
+
+fn main() {
+ let (mut a, b);
+ let mut c;
+ let d = Struct { a: 0, b: 1 };
+ Struct { a, b, c } = Struct { a: 0, b: 1 }; //~ ERROR does not have a field named `c`
+ Struct { a, ..d } = Struct { a: 1, b: 2 };
+ //~^ ERROR functional record updates are not allowed in destructuring assignments
+ Struct { a, .. }; //~ ERROR base expression required after `..`
+}
diff --git a/src/test/ui/destructuring-assignment/struct_destructure_fail.stderr b/src/test/ui/destructuring-assignment/struct_destructure_fail.stderr
new file mode 100644
index 0000000000000..4da4698804f1a
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/struct_destructure_fail.stderr
@@ -0,0 +1,21 @@
+error: functional record updates are not allowed in destructuring assignments
+ --> $DIR/struct_destructure_fail.rs:12:19
+ |
+LL | Struct { a, ..d } = Struct { a: 1, b: 2 };
+ | ^ help: consider removing the trailing pattern
+
+error: base expression required after `..`
+ --> $DIR/struct_destructure_fail.rs:14:19
+ |
+LL | Struct { a, .. };
+ | ^ add a base expression here
+
+error[E0026]: struct `Struct` does not have a field named `c`
+ --> $DIR/struct_destructure_fail.rs:11:20
+ |
+LL | Struct { a, b, c } = Struct { a: 0, b: 1 };
+ | ^ struct `Struct` does not have this field
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0026`.
diff --git a/src/test/ui/destructuring-assignment/tuple_struct_destructure.rs b/src/test/ui/destructuring-assignment/tuple_struct_destructure.rs
new file mode 100644
index 0000000000000..106a9b16db459
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/tuple_struct_destructure.rs
@@ -0,0 +1,34 @@
+// run-pass
+
+#![feature(destructuring_assignment)]
+
+struct TupleStruct<S, T>(S, T);
+
+impl<S, T> TupleStruct<S, T> {
+ fn assign(self, first: &mut S, second: &mut T) {
+ // Test usage of `Self` instead of the struct name:
+ Self(*first, *second) = self
+ }
+}
+
+enum Enum<S, T> {
+ SingleVariant(S, T)
+}
+
+type Alias<S> = Enum<S, isize>;
+
+fn main() {
+ let (mut a, mut b);
+ TupleStruct(a, b) = TupleStruct(0, 1);
+ assert_eq!((a, b), (0, 1));
+ TupleStruct(a, .., b) = TupleStruct(1, 2);
+ assert_eq!((a, b), (1, 2));
+ TupleStruct(..) = TupleStruct(3, 4);
+ assert_eq!((a, b), (1, 2));
+ TupleStruct(5,6).assign(&mut a, &mut b);
+ assert_eq!((a, b), (5, 6));
+ Enum::SingleVariant(a, b) = Enum::SingleVariant(7, 8);
+ assert_eq!((a, b), (7, 8));
+ Alias::SingleVariant(a, b) = Alias::SingleVariant(9, 10);
+ assert_eq!((a, b), (9, 10));
+}
diff --git a/src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.rs b/src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.rs
new file mode 100644
index 0000000000000..61ae42a51751f
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.rs
@@ -0,0 +1,42 @@
+#![feature(destructuring_assignment)]
+
+struct TupleStruct<S, T>(S, T);
+
+enum Enum<S, T> {
+ SingleVariant(S, T)
+}
+
+type Alias<S> = Enum<S, isize>;
+
+trait Test {
+ fn test() -> TupleStruct<isize, isize> {
+ TupleStruct(0, 0)
+ }
+}
+
+impl Test for Alias<isize> {}
+
+fn test() -> TupleStruct<isize, isize> {
+ TupleStruct(0, 0)
+}
+
+fn main() {
+ let (mut a, mut b);
+ TupleStruct(a, .., b, ..) = TupleStruct(0, 1);
+ //~^ ERROR `..` can only be used once per tuple struct or variant pattern
+ Enum::SingleVariant(a, .., b, ..) = Enum::SingleVariant(0, 1);
+ //~^ ERROR `..` can only be used once per tuple struct or variant pattern
+
+ TupleStruct(a, a, b) = TupleStruct(1, 2);
+ //~^ ERROR this pattern has 3 fields, but the corresponding tuple struct has 2 fields
+ Enum::SingleVariant(a, a, b) = Enum::SingleVariant(1, 2);
+ //~^ ERROR this pattern has 3 fields, but the corresponding tuple variant has 2 fields
+
+ // Check if `test` is recognized as not a tuple struct but a function call:
+ test() = TupleStruct(0, 0);
+ //~^ ERROR invalid left-hand side of assignment
+ (test)() = TupleStruct(0, 0);
+ //~^ ERROR invalid left-hand side of assignment
+ <Alias::<isize> as Test>::test() = TupleStruct(0, 0);
+ //~^ ERROR invalid left-hand side of assignment
+}
diff --git a/src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.stderr b/src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.stderr
new file mode 100644
index 0000000000000..863eedecf7697
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/tuple_struct_destructure_fail.stderr
@@ -0,0 +1,62 @@
+error: `..` can only be used once per tuple struct or variant pattern
+ --> $DIR/tuple_struct_destructure_fail.rs:25:27
+ |
+LL | TupleStruct(a, .., b, ..) = TupleStruct(0, 1);
+ | -- ^^ can only be used once per tuple struct or variant pattern
+ | |
+ | previously used here
+
+error: `..` can only be used once per tuple struct or variant pattern
+ --> $DIR/tuple_struct_destructure_fail.rs:27:35
+ |
+LL | Enum::SingleVariant(a, .., b, ..) = Enum::SingleVariant(0, 1);
+ | -- ^^ can only be used once per tuple struct or variant pattern
+ | |
+ | previously used here
+
+error[E0023]: this pattern has 3 fields, but the corresponding tuple struct has 2 fields
+ --> $DIR/tuple_struct_destructure_fail.rs:30:5
+ |
+LL | struct TupleStruct<S, T>(S, T);
+ | ------------------------------- tuple struct defined here
+...
+LL | TupleStruct(a, a, b) = TupleStruct(1, 2);
+ | ^^^^^^^^^^^^^^^^^^^^ expected 2 fields, found 3
+
+error[E0023]: this pattern has 3 fields, but the corresponding tuple variant has 2 fields
+ --> $DIR/tuple_struct_destructure_fail.rs:32:5
+ |
+LL | SingleVariant(S, T)
+ | ------------------- tuple variant defined here
+...
+LL | Enum::SingleVariant(a, a, b) = Enum::SingleVariant(1, 2);
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected 2 fields, found 3
+
+error[E0070]: invalid left-hand side of assignment
+ --> $DIR/tuple_struct_destructure_fail.rs:36:12
+ |
+LL | test() = TupleStruct(0, 0);
+ | ------ ^
+ | |
+ | cannot assign to this expression
+
+error[E0070]: invalid left-hand side of assignment
+ --> $DIR/tuple_struct_destructure_fail.rs:38:14
+ |
+LL | (test)() = TupleStruct(0, 0);
+ | -------- ^
+ | |
+ | cannot assign to this expression
+
+error[E0070]: invalid left-hand side of assignment
+ --> $DIR/tuple_struct_destructure_fail.rs:40:38
+ |
+LL | <Alias::<isize> as Test>::test() = TupleStruct(0, 0);
+ | -------------------------------- ^
+ | |
+ | cannot assign to this expression
+
+error: aborting due to 7 previous errors
+
+Some errors have detailed explanations: E0023, E0070.
+For more information about an error, try `rustc --explain E0023`.
diff --git a/src/test/ui/destructuring-assignment/underscore-range-expr-gating.rs b/src/test/ui/destructuring-assignment/underscore-range-expr-gating.rs
new file mode 100644
index 0000000000000..b41f2f52a3d6f
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/underscore-range-expr-gating.rs
@@ -0,0 +1,8 @@
+fn main() {}
+
+struct S { x : u32 }
+
+#[cfg(FALSE)]
+fn foo() {
+ S { x: 5, .. }; //~ ERROR destructuring assignments are unstable
+}
diff --git a/src/test/ui/destructuring-assignment/underscore-range-expr-gating.stderr b/src/test/ui/destructuring-assignment/underscore-range-expr-gating.stderr
new file mode 100644
index 0000000000000..442e36cd3065e
--- /dev/null
+++ b/src/test/ui/destructuring-assignment/underscore-range-expr-gating.stderr
@@ -0,0 +1,12 @@
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/underscore-range-expr-gating.rs:7:15
+ |
+LL | S { x: 5, .. };
+ | ^^
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/issues/issue-77218.rs b/src/test/ui/issues/issue-77218.rs
index bc992c21dca5c..a6a2401795ff4 100644
--- a/src/test/ui/issues/issue-77218.rs
+++ b/src/test/ui/issues/issue-77218.rs
@@ -1,7 +1,11 @@
fn main() {
let value = [7u8];
- while Some(0) = value.get(0) { //~ ERROR mismatched types
- //~^ NOTE expected `bool`, found `()`
- //~| HELP you might have meant to use pattern matching
+ while Some(0) = value.get(0) { //~ ERROR destructuring assignments are unstable
+ //~| ERROR invalid left-hand side of assignment
+ //~| ERROR mismatched types
+ //~| ERROR mismatched types
+
+ // FIXME The following diagnostic should also be emitted
+ // HELP you might have meant to use pattern matching
}
}
diff --git a/src/test/ui/issues/issue-77218.stderr b/src/test/ui/issues/issue-77218.stderr
index eca44725eb258..4f6fbaa2265d5 100644
--- a/src/test/ui/issues/issue-77218.stderr
+++ b/src/test/ui/issues/issue-77218.stderr
@@ -1,14 +1,38 @@
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/issue-77218.rs:3:19
+ |
+LL | while Some(0) = value.get(0) {
+ | ------- ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error[E0070]: invalid left-hand side of assignment
+ --> $DIR/issue-77218.rs:3:19
+ |
+LL | while Some(0) = value.get(0) {
+ | - ^
+ | |
+ | cannot assign to this expression
+
+error[E0308]: mismatched types
+ --> $DIR/issue-77218.rs:3:16
+ |
+LL | while Some(0) = value.get(0) {
+ | ^
+ | |
+ | expected integer, found `&u8`
+ | help: consider dereferencing the borrow: `*0`
+
error[E0308]: mismatched types
--> $DIR/issue-77218.rs:3:11
|
LL | while Some(0) = value.get(0) {
| ^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found `()`
- |
-help: you might have meant to use pattern matching
- |
-LL | while let Some(0) = value.get(0) {
- | ^^^
-error: aborting due to previous error
+error: aborting due to 4 previous errors
-For more information about this error, try `rustc --explain E0308`.
+Some errors have detailed explanations: E0070, E0308, E0658.
+For more information about an error, try `rustc --explain E0070`.
diff --git a/src/test/ui/suggestions/if-let-typo.rs b/src/test/ui/suggestions/if-let-typo.rs
index 87def13c476c7..688b6e8265826 100644
--- a/src/test/ui/suggestions/if-let-typo.rs
+++ b/src/test/ui/suggestions/if-let-typo.rs
@@ -2,7 +2,12 @@ fn main() {
let foo = Some(0);
let bar = None;
if Some(x) = foo {} //~ ERROR cannot find value `x` in this scope
+ //~^ ERROR mismatched types
+ //~^^ ERROR destructuring assignments are unstable
if Some(foo) = bar {} //~ ERROR mismatched types
+ //~^ ERROR destructuring assignments are unstable
if 3 = foo {} //~ ERROR mismatched types
if Some(3) = foo {} //~ ERROR mismatched types
+ //~^ ERROR destructuring assignments are unstable
+ //~^^ ERROR invalid left-hand side of assignment
}
diff --git a/src/test/ui/suggestions/if-let-typo.stderr b/src/test/ui/suggestions/if-let-typo.stderr
index d8e50cae55ad1..ce1ee0cd06d48 100644
--- a/src/test/ui/suggestions/if-let-typo.stderr
+++ b/src/test/ui/suggestions/if-let-typo.stderr
@@ -9,23 +9,53 @@ help: you might have meant to use pattern matching
LL | if let Some(x) = foo {}
| ^^^
-error[E0308]: mismatched types
- --> $DIR/if-let-typo.rs:5:8
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/if-let-typo.rs:4:16
+ |
+LL | if Some(x) = foo {}
+ | ------- ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/if-let-typo.rs:7:18
|
LL | if Some(foo) = bar {}
- | ^^^^^^^^^^^^^^^ expected `bool`, found `()`
+ | --------- ^
+ | |
+ | cannot assign to this expression
|
-help: you might have meant to use pattern matching
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/if-let-typo.rs:10:16
|
-LL | if let Some(foo) = bar {}
- | ^^^
-help: you might have meant to compare for equality
+LL | if Some(3) = foo {}
+ | ------- ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
+error[E0308]: mismatched types
+ --> $DIR/if-let-typo.rs:4:8
+ |
+LL | if Some(x) = foo {}
+ | ^^^^^^^^^^^^^ expected `bool`, found `()`
+
+error[E0308]: mismatched types
+ --> $DIR/if-let-typo.rs:7:8
|
-LL | if Some(foo) == bar {}
- | ^^
+LL | if Some(foo) = bar {}
+ | ^^^^^^^^^^^^^^^ expected `bool`, found `()`
error[E0308]: mismatched types
- --> $DIR/if-let-typo.rs:6:8
+ --> $DIR/if-let-typo.rs:9:8
|
LL | if 3 = foo {}
| ^^^^^^^ expected `bool`, found `()`
@@ -35,22 +65,21 @@ help: you might have meant to use pattern matching
LL | if let 3 = foo {}
| ^^^
+error[E0070]: invalid left-hand side of assignment
+ --> $DIR/if-let-typo.rs:10:16
+ |
+LL | if Some(3) = foo {}
+ | - ^
+ | |
+ | cannot assign to this expression
+
error[E0308]: mismatched types
- --> $DIR/if-let-typo.rs:7:8
+ --> $DIR/if-let-typo.rs:10:8
|
LL | if Some(3) = foo {}
| ^^^^^^^^^^^^^ expected `bool`, found `()`
- |
-help: you might have meant to use pattern matching
- |
-LL | if let Some(3) = foo {}
- | ^^^
-help: you might have meant to compare for equality
- |
-LL | if Some(3) == foo {}
- | ^^
-error: aborting due to 4 previous errors
+error: aborting due to 9 previous errors
-Some errors have detailed explanations: E0308, E0425.
-For more information about an error, try `rustc --explain E0308`.
+Some errors have detailed explanations: E0070, E0308, E0425, E0658.
+For more information about an error, try `rustc --explain E0070`.
diff --git a/src/tools/clippy/clippy_lints/src/utils/ast_utils.rs b/src/tools/clippy/clippy_lints/src/utils/ast_utils.rs
index 0e9feef3746e7..7b65e664867ff 100644
--- a/src/tools/clippy/clippy_lints/src/utils/ast_utils.rs
+++ b/src/tools/clippy/clippy_lints/src/utils/ast_utils.rs
@@ -107,6 +107,15 @@ pub fn eq_expr_opt(l: &Option<P<Expr>>, r: &Option<P<Expr>>) -> bool {
both(l, r, |l, r| eq_expr(l, r))
}
+pub fn eq_struct_rest(l: &StructRest, r: &StructRest) -> bool {
+ match (l, r) {
+ (StructRest::Base(lb), StructRest::Base(rb)) => eq_expr(lb, rb),
+ (StructRest::Rest(_), StructRest::Rest(_)) => true,
+ (StructRest::None, StructRest::None) => true,
+ _ => false,
+ }
+}
+
pub fn eq_expr(l: &Expr, r: &Expr) -> bool {
use ExprKind::*;
if !over(&l.attrs, &r.attrs, |l, r| eq_attr(l, r)) {
@@ -150,7 +159,7 @@ pub fn eq_expr(l: &Expr, r: &Expr) -> bool {
(Path(lq, lp), Path(rq, rp)) => both(lq, rq, |l, r| eq_qself(l, r)) && eq_path(lp, rp),
(MacCall(l), MacCall(r)) => eq_mac_call(l, r),
(Struct(lp, lfs, lb), Struct(rp, rfs, rb)) => {
- eq_path(lp, rp) && eq_expr_opt(lb, rb) && unordered_over(lfs, rfs, |l, r| eq_field(l, r))
+ eq_path(lp, rp) && eq_struct_rest(lb, rb) && unordered_over(lfs, rfs, |l, r| eq_field(l, r))
},
_ => false,
}
diff --git a/src/tools/clippy/tests/ui/crashes/ice-6250.stderr b/src/tools/clippy/tests/ui/crashes/ice-6250.stderr
index 8241dcd8feb7b..c38727316cd4e 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-6250.stderr
+++ b/src/tools/clippy/tests/ui/crashes/ice-6250.stderr
@@ -1,3 +1,14 @@
+error[E0658]: destructuring assignments are unstable
+ --> $DIR/ice-6250.rs:12:25
+ |
+LL | Some(reference) = cache.data.get(key) {
+ | --------------- ^
+ | |
+ | cannot assign to this expression
+ |
+ = note: see issue #71126 <https://github.com/rust-lang/rust/issues/71126> for more information
+ = help: add `#![feature(destructuring_assignment)]` to the crate attributes to enable
+
error[E0601]: `main` function not found in crate `ice_6250`
--> $DIR/ice-6250.rs:4:1
|
@@ -10,18 +21,22 @@ LL | | }
LL | | }
| |_^ consider adding a `main` function to `$DIR/ice-6250.rs`
+error[E0308]: mismatched types
+ --> $DIR/ice-6250.rs:12:14
+ |
+LL | Some(reference) = cache.data.get(key) {
+ | ^^^^^^^^^
+ | |
+ | expected integer, found `&i32`
+ | help: consider dereferencing the borrow: `*reference`
+
error[E0308]: mismatched types
--> $DIR/ice-6250.rs:12:9
|
LL | Some(reference) = cache.data.get(key) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found `()`
- |
-help: you might have meant to use pattern matching
- |
-LL | let Some(reference) = cache.data.get(key) {
- | ^^^
-error: aborting due to 2 previous errors
+error: aborting due to 4 previous errors
-Some errors have detailed explanations: E0308, E0601.
+Some errors have detailed explanations: E0308, E0601, E0658.
For more information about an error, try `rustc --explain E0308`.