From 94c300a4522f3386546ba77a21865bb78fe9bba8 Mon Sep 17 00:00:00 2001
From: Rob Pilling <robpilling@gmail.com>
Date: Sun, 7 Nov 2021 22:41:35 +0000
Subject: [PATCH 1/5] Suggest tuple-parentheses when passing N arguments to an
N-tuple argument
---
.../rustc_typeck/src/check/fn_ctxt/checks.rs | 73 +++++++++++++++++--
1 file changed, 67 insertions(+), 6 deletions(-)
diff --git a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
index c39199f84b527..5f3507846ba9b 100644
--- a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
+++ b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
@@ -28,6 +28,11 @@ use crate::structured_errors::StructuredDiagnostic;
use std::iter;
use std::slice;
+enum FnArgsAsTuple<'hir> {
+ Single(&'hir hir::Expr<'hir>),
+ Multi { first: &'hir hir::Expr<'hir>, last: &'hir hir::Expr<'hir> },
+}
+
impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
pub(in super::super) fn check_casts(&self) {
let mut deferred_cast_checks = self.deferred_cast_checks.borrow_mut();
@@ -127,8 +132,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
let expected_arg_count = formal_input_tys.len();
- // expected_count, arg_count, error_code, sugg_unit
- let mut error: Option<(usize, usize, &str, bool)> = None;
+ // expected_count, arg_count, error_code, sugg_unit, sugg_tuple_wrap_args
+ let mut error: Option<(usize, usize, &str, bool, Option<FnArgsAsTuple<'_>>)> = None;
// If the arguments should be wrapped in a tuple (ex: closures), unwrap them here
let (formal_input_tys, expected_input_tys) = if tuple_arguments == TupleArguments {
@@ -138,7 +143,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
ty::Tuple(arg_types) => {
// Argument length differs
if arg_types.len() != provided_args.len() {
- error = Some((arg_types.len(), provided_args.len(), "E0057", false));
+ error = Some((arg_types.len(), provided_args.len(), "E0057", false, None));
}
let expected_input_tys = match expected_input_tys.get(0) {
Some(&ty) => match ty.kind() {
@@ -169,7 +174,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
if supplied_arg_count >= expected_arg_count {
(formal_input_tys.to_vec(), expected_input_tys)
} else {
- error = Some((expected_arg_count, supplied_arg_count, "E0060", false));
+ error = Some((expected_arg_count, supplied_arg_count, "E0060", false, None));
(self.err_args(supplied_arg_count), vec![])
}
} else {
@@ -181,7 +186,43 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
} else {
false
};
- error = Some((expected_arg_count, supplied_arg_count, "E0061", sugg_unit));
+
+ // are we passing elements of a tuple without the tuple parentheses?
+ let chosen_arg_tys = if expected_input_tys.is_empty() {
+ // In most cases we can use expected_arg_tys, but some callers won't have the type
+ // information, in which case we fall back to the types from the input expressions.
+ formal_input_tys
+ } else {
+ &*expected_input_tys
+ };
+
+ let sugg_tuple_wrap_args = chosen_arg_tys
+ .get(0)
+ .cloned()
+ .map(|arg_ty| self.resolve_vars_if_possible(arg_ty))
+ .and_then(|arg_ty| match arg_ty.kind() {
+ ty::Tuple(tup_elems) => Some(tup_elems),
+ _ => None,
+ })
+ .and_then(|tup_elems| {
+ if tup_elems.len() == supplied_arg_count && chosen_arg_tys.len() == 1 {
+ match provided_args {
+ [] => None,
+ [single] => Some(FnArgsAsTuple::Single(single)),
+ [first, .., last] => Some(FnArgsAsTuple::Multi { first, last }),
+ }
+ } else {
+ None
+ }
+ });
+
+ error = Some((
+ expected_arg_count,
+ supplied_arg_count,
+ "E0061",
+ sugg_unit,
+ sugg_tuple_wrap_args,
+ ));
(self.err_args(supplied_arg_count), vec![])
};
@@ -305,7 +346,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
}
// If there was an error in parameter count, emit that here
- if let Some((expected_count, arg_count, err_code, sugg_unit)) = error {
+ if let Some((expected_count, arg_count, err_code, sugg_unit, sugg_tuple_wrap_args)) = error
+ {
let (span, start_span, args, ctor_of) = match &call_expr.kind {
hir::ExprKind::Call(
hir::Expr {
@@ -408,6 +450,25 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
String::from("()"),
Applicability::MachineApplicable,
);
+ } else if let Some(tuple_fn_arg) = sugg_tuple_wrap_args {
+ use FnArgsAsTuple::*;
+
+ let spans = match tuple_fn_arg {
+ Multi { first, last } => vec![
+ (first.span.shrink_to_lo(), '('.to_string()),
+ (last.span.shrink_to_hi(), ')'.to_string()),
+ ],
+ Single(single) => vec![
+ (single.span.shrink_to_lo(), '('.to_string()),
+ (single.span.shrink_to_hi(), ",)".to_string()),
+ ],
+ };
+
+ err.multipart_suggestion(
+ "use parentheses to construct a tuple",
+ spans,
+ Applicability::MachineApplicable,
+ );
} else {
err.span_label(
span,
From 80059f99424c64d10f073ab5c502856d46b1c26d Mon Sep 17 00:00:00 2001
From: Rob Pilling <robpilling@gmail.com>
Date: Tue, 9 Nov 2021 23:20:26 +0000
Subject: [PATCH 2/5] Test tuple suggestions, including
tuple-as-function-argument
---
.../suggestions/args-instead-of-tuple.fixed | 18 +++++++
.../ui/suggestions/args-instead-of-tuple.rs | 18 +++++++
.../suggestions/args-instead-of-tuple.stderr | 52 +++++++++++++++++++
3 files changed, 88 insertions(+)
create mode 100644 src/test/ui/suggestions/args-instead-of-tuple.fixed
create mode 100644 src/test/ui/suggestions/args-instead-of-tuple.rs
create mode 100644 src/test/ui/suggestions/args-instead-of-tuple.stderr
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.fixed b/src/test/ui/suggestions/args-instead-of-tuple.fixed
new file mode 100644
index 0000000000000..adb832b8a7b74
--- /dev/null
+++ b/src/test/ui/suggestions/args-instead-of-tuple.fixed
@@ -0,0 +1,18 @@
+// Test suggesting tuples where bare arguments may have been passed
+// See issue #86481 for details.
+
+// run-rustfix
+
+fn main() {
+ let _: Result<(i32, i8), ()> = Ok((1, 2));
+ //~^ ERROR this enum variant takes 1 argument but 2 arguments were supplied
+ let _: Option<(i32, i8, &'static str)> = Some((1, 2, "hi"));
+ //~^ ERROR this enum variant takes 1 argument but 3 arguments were supplied
+ let _: Option<()> = Some(());
+ //~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
+
+ f((1, 2)); //~ ERROR this function takes 1 argument
+}
+
+fn f(_: (i32, i32)) {
+}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.rs b/src/test/ui/suggestions/args-instead-of-tuple.rs
new file mode 100644
index 0000000000000..8dbc58daeb1f5
--- /dev/null
+++ b/src/test/ui/suggestions/args-instead-of-tuple.rs
@@ -0,0 +1,18 @@
+// Test suggesting tuples where bare arguments may have been passed
+// See issue #86481 for details.
+
+// run-rustfix
+
+fn main() {
+ let _: Result<(i32, i8), ()> = Ok(1, 2);
+ //~^ ERROR this enum variant takes 1 argument but 2 arguments were supplied
+ let _: Option<(i32, i8, &'static str)> = Some(1, 2, "hi");
+ //~^ ERROR this enum variant takes 1 argument but 3 arguments were supplied
+ let _: Option<()> = Some();
+ //~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
+
+ f(1, 2); //~ ERROR this function takes 1 argument
+}
+
+fn f(_: (i32, i32)) {
+}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.stderr b/src/test/ui/suggestions/args-instead-of-tuple.stderr
new file mode 100644
index 0000000000000..95bbbdb274964
--- /dev/null
+++ b/src/test/ui/suggestions/args-instead-of-tuple.stderr
@@ -0,0 +1,52 @@
+error[E0061]: this enum variant takes 1 argument but 2 arguments were supplied
+ --> $DIR/args-instead-of-tuple.rs:7:36
+ |
+LL | let _: Result<(i32, i8), ()> = Ok(1, 2);
+ | ^^ - - supplied 2 arguments
+ |
+help: use parentheses to construct a tuple
+ |
+LL | let _: Result<(i32, i8), ()> = Ok((1, 2));
+ | + +
+
+error[E0061]: this enum variant takes 1 argument but 3 arguments were supplied
+ --> $DIR/args-instead-of-tuple.rs:9:46
+ |
+LL | let _: Option<(i32, i8, &'static str)> = Some(1, 2, "hi");
+ | ^^^^ - - ---- supplied 3 arguments
+ |
+help: use parentheses to construct a tuple
+ |
+LL | let _: Option<(i32, i8, &'static str)> = Some((1, 2, "hi"));
+ | + +
+
+error[E0061]: this enum variant takes 1 argument but 0 arguments were supplied
+ --> $DIR/args-instead-of-tuple.rs:11:25
+ |
+LL | let _: Option<()> = Some();
+ | ^^^^-- supplied 0 arguments
+ |
+help: expected the unit value `()`; create it with empty parentheses
+ |
+LL | let _: Option<()> = Some(());
+ | ++
+
+error[E0061]: this function takes 1 argument but 2 arguments were supplied
+ --> $DIR/args-instead-of-tuple.rs:14:5
+ |
+LL | f(1, 2);
+ | ^ - - supplied 2 arguments
+ |
+note: function defined here
+ --> $DIR/args-instead-of-tuple.rs:17:4
+ |
+LL | fn f(_: (i32, i32)) {
+ | ^ -------------
+help: use parentheses to construct a tuple
+ |
+LL | f((1, 2));
+ | + +
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0061`.
From 54d2d30662c2832554bb127f017f7a311bb62b4e Mon Sep 17 00:00:00 2001
From: Rob Pilling <robpilling@gmail.com>
Date: Sun, 5 Dec 2021 21:41:33 +0000
Subject: [PATCH 3/5] Compare tuple element & arg types before suggesting a
tuple
---
.../rustc_typeck/src/check/fn_ctxt/checks.rs | 53 +++++++++++--------
.../args-instead-of-tuple-errors.rs | 13 +++++
.../args-instead-of-tuple-errors.stderr | 25 +++++++++
.../suggestions/args-instead-of-tuple.fixed | 4 +-
.../ui/suggestions/args-instead-of-tuple.rs | 4 +-
.../suggestions/args-instead-of-tuple.stderr | 12 ++---
6 files changed, 79 insertions(+), 32 deletions(-)
create mode 100644 src/test/ui/suggestions/args-instead-of-tuple-errors.rs
create mode 100644 src/test/ui/suggestions/args-instead-of-tuple-errors.stderr
diff --git a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
index 5f3507846ba9b..a94e6b480d643 100644
--- a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
+++ b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
@@ -18,7 +18,7 @@ use rustc_hir::def_id::DefId;
use rustc_hir::{ExprKind, Node, QPath};
use rustc_middle::ty::adjustment::AllowTwoPhase;
use rustc_middle::ty::fold::TypeFoldable;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::{self, ParamEnv, Ty};
use rustc_session::Session;
use rustc_span::symbol::Ident;
use rustc_span::{self, MultiSpan, Span};
@@ -188,33 +188,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
};
// are we passing elements of a tuple without the tuple parentheses?
- let chosen_arg_tys = if expected_input_tys.is_empty() {
- // In most cases we can use expected_arg_tys, but some callers won't have the type
+ let expected_input_tys = if expected_input_tys.is_empty() {
+ // In most cases we can use expected_input_tys, but some callers won't have the type
// information, in which case we fall back to the types from the input expressions.
formal_input_tys
} else {
&*expected_input_tys
};
- let sugg_tuple_wrap_args = chosen_arg_tys
- .get(0)
- .cloned()
- .map(|arg_ty| self.resolve_vars_if_possible(arg_ty))
- .and_then(|arg_ty| match arg_ty.kind() {
- ty::Tuple(tup_elems) => Some(tup_elems),
- _ => None,
- })
- .and_then(|tup_elems| {
- if tup_elems.len() == supplied_arg_count && chosen_arg_tys.len() == 1 {
- match provided_args {
- [] => None,
- [single] => Some(FnArgsAsTuple::Single(single)),
- [first, .., last] => Some(FnArgsAsTuple::Multi { first, last }),
- }
- } else {
- None
- }
- });
+ let sugg_tuple_wrap_args = self.suggested_tuple_wrap(expected_input_tys, provided_args);
error = Some((
expected_arg_count,
@@ -518,6 +500,33 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
}
}
+ fn suggested_tuple_wrap(
+ &self,
+ expected_input_tys: &[Ty<'tcx>],
+ provided_args: &'tcx [hir::Expr<'tcx>],
+ ) -> Option<FnArgsAsTuple<'_>> {
+ let [expected_arg_type] = &expected_input_tys[..] else { return None };
+
+ let ty::Tuple(expected_elems) = self.resolve_vars_if_possible(*expected_arg_type).kind()
+ else { return None };
+
+ let expected_types: Vec<_> = expected_elems.iter().map(|k| k.expect_ty()).collect();
+ let supplied_types: Vec<_> = provided_args.iter().map(|arg| self.check_expr(arg)).collect();
+
+ let all_match = iter::zip(expected_types, supplied_types)
+ .all(|(expected, supplied)| self.can_eq(ParamEnv::empty(), expected, supplied).is_ok());
+
+ if all_match {
+ match provided_args {
+ [] => None,
+ [single] => Some(FnArgsAsTuple::Single(single)),
+ [first, .., last] => Some(FnArgsAsTuple::Multi { first, last }),
+ }
+ } else {
+ None
+ }
+ }
+
// AST fragment checking
pub(in super::super) fn check_lit(
&self,
diff --git a/src/test/ui/suggestions/args-instead-of-tuple-errors.rs b/src/test/ui/suggestions/args-instead-of-tuple-errors.rs
new file mode 100644
index 0000000000000..c4e9c68e219e6
--- /dev/null
+++ b/src/test/ui/suggestions/args-instead-of-tuple-errors.rs
@@ -0,0 +1,13 @@
+// Ensure we don't suggest tuple-wrapping when we'd end up with a type error
+
+fn main() {
+ // we shouldn't suggest to fix these - `2` isn't a `bool`
+
+ let _: Option<(i32, bool)> = Some(1, 2);
+ //~^ ERROR this enum variant takes 1 argument but 2 arguments were supplied
+ int_bool(1, 2);
+ //~^ ERROR this function takes 1 argument but 2 arguments were supplied
+}
+
+fn int_bool(_: (i32, bool)) {
+}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr b/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr
new file mode 100644
index 0000000000000..c53c8bbdcc9df
--- /dev/null
+++ b/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr
@@ -0,0 +1,25 @@
+error[E0061]: this enum variant takes 1 argument but 2 arguments were supplied
+ --> $DIR/args-instead-of-tuple-errors.rs:6:34
+ |
+LL | let _: Option<(i32, bool)> = Some(1, 2);
+ | ^^^^ - - supplied 2 arguments
+ | |
+ | expected 1 argument
+
+error[E0061]: this function takes 1 argument but 2 arguments were supplied
+ --> $DIR/args-instead-of-tuple-errors.rs:8:5
+ |
+LL | int_bool(1, 2);
+ | ^^^^^^^^ - - supplied 2 arguments
+ | |
+ | expected 1 argument
+ |
+note: function defined here
+ --> $DIR/args-instead-of-tuple-errors.rs:12:4
+ |
+LL | fn int_bool(_: (i32, bool)) {
+ | ^^^^^^^^ --------------
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0061`.
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.fixed b/src/test/ui/suggestions/args-instead-of-tuple.fixed
index adb832b8a7b74..095be95f18586 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple.fixed
+++ b/src/test/ui/suggestions/args-instead-of-tuple.fixed
@@ -11,8 +11,8 @@ fn main() {
let _: Option<()> = Some(());
//~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
- f((1, 2)); //~ ERROR this function takes 1 argument
+ two_ints((1, 2)); //~ ERROR this function takes 1 argument
}
-fn f(_: (i32, i32)) {
+fn two_ints(_: (i32, i32)) {
}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.rs b/src/test/ui/suggestions/args-instead-of-tuple.rs
index 8dbc58daeb1f5..3466a46df848e 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple.rs
+++ b/src/test/ui/suggestions/args-instead-of-tuple.rs
@@ -11,8 +11,8 @@ fn main() {
let _: Option<()> = Some();
//~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
- f(1, 2); //~ ERROR this function takes 1 argument
+ two_ints(1, 2); //~ ERROR this function takes 1 argument
}
-fn f(_: (i32, i32)) {
+fn two_ints(_: (i32, i32)) {
}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.stderr b/src/test/ui/suggestions/args-instead-of-tuple.stderr
index 95bbbdb274964..1bf7e7a8d171b 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple.stderr
+++ b/src/test/ui/suggestions/args-instead-of-tuple.stderr
@@ -34,18 +34,18 @@ LL | let _: Option<()> = Some(());
error[E0061]: this function takes 1 argument but 2 arguments were supplied
--> $DIR/args-instead-of-tuple.rs:14:5
|
-LL | f(1, 2);
- | ^ - - supplied 2 arguments
+LL | two_ints(1, 2);
+ | ^^^^^^^^ - - supplied 2 arguments
|
note: function defined here
--> $DIR/args-instead-of-tuple.rs:17:4
|
-LL | fn f(_: (i32, i32)) {
- | ^ -------------
+LL | fn two_ints(_: (i32, i32)) {
+ | ^^^^^^^^ -------------
help: use parentheses to construct a tuple
|
-LL | f((1, 2));
- | + +
+LL | two_ints((1, 2));
+ | + +
error: aborting due to 4 previous errors
From a129a85144efb67bfd8f380a758ed6be41d3e29b Mon Sep 17 00:00:00 2001
From: Rob Pilling <robpilling@gmail.com>
Date: Sun, 16 Jan 2022 21:47:44 +0000
Subject: [PATCH 4/5] Handle generics with ParamEnv
---
.../rustc_typeck/src/check/fn_ctxt/checks.rs | 4 +--
.../suggestions/args-instead-of-tuple.fixed | 9 +++++
.../ui/suggestions/args-instead-of-tuple.rs | 9 +++++
.../suggestions/args-instead-of-tuple.stderr | 36 +++++++++++++++++--
4 files changed, 54 insertions(+), 4 deletions(-)
diff --git a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
index a94e6b480d643..af0c9e5e5090e 100644
--- a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
+++ b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
@@ -18,7 +18,7 @@ use rustc_hir::def_id::DefId;
use rustc_hir::{ExprKind, Node, QPath};
use rustc_middle::ty::adjustment::AllowTwoPhase;
use rustc_middle::ty::fold::TypeFoldable;
-use rustc_middle::ty::{self, ParamEnv, Ty};
+use rustc_middle::ty::{self, Ty};
use rustc_session::Session;
use rustc_span::symbol::Ident;
use rustc_span::{self, MultiSpan, Span};
@@ -514,7 +514,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
let supplied_types: Vec<_> = provided_args.iter().map(|arg| self.check_expr(arg)).collect();
let all_match = iter::zip(expected_types, supplied_types)
- .all(|(expected, supplied)| self.can_eq(ParamEnv::empty(), expected, supplied).is_ok());
+ .all(|(expected, supplied)| self.can_eq(self.param_env, expected, supplied).is_ok());
if all_match {
match provided_args {
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.fixed b/src/test/ui/suggestions/args-instead-of-tuple.fixed
index 095be95f18586..c9b8a41d469b9 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple.fixed
+++ b/src/test/ui/suggestions/args-instead-of-tuple.fixed
@@ -12,7 +12,16 @@ fn main() {
//~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
two_ints((1, 2)); //~ ERROR this function takes 1 argument
+
+ with_generic((3, 4)); //~ ERROR this function takes 1 argument
}
fn two_ints(_: (i32, i32)) {
}
+
+fn with_generic<T: Copy + Send>((a, b): (i32, T)) {
+ if false {
+ // test generics/bound handling
+ with_generic((a, b)); //~ ERROR this function takes 1 argument
+ }
+}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.rs b/src/test/ui/suggestions/args-instead-of-tuple.rs
index 3466a46df848e..d4cc3024dd0d2 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple.rs
+++ b/src/test/ui/suggestions/args-instead-of-tuple.rs
@@ -12,7 +12,16 @@ fn main() {
//~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
two_ints(1, 2); //~ ERROR this function takes 1 argument
+
+ with_generic(3, 4); //~ ERROR this function takes 1 argument
}
fn two_ints(_: (i32, i32)) {
}
+
+fn with_generic<T: Copy + Send>((a, b): (i32, T)) {
+ if false {
+ // test generics/bound handling
+ with_generic(a, b); //~ ERROR this function takes 1 argument
+ }
+}
diff --git a/src/test/ui/suggestions/args-instead-of-tuple.stderr b/src/test/ui/suggestions/args-instead-of-tuple.stderr
index 1bf7e7a8d171b..172db7ee3df38 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple.stderr
+++ b/src/test/ui/suggestions/args-instead-of-tuple.stderr
@@ -38,7 +38,7 @@ LL | two_ints(1, 2);
| ^^^^^^^^ - - supplied 2 arguments
|
note: function defined here
- --> $DIR/args-instead-of-tuple.rs:17:4
+ --> $DIR/args-instead-of-tuple.rs:19:4
|
LL | fn two_ints(_: (i32, i32)) {
| ^^^^^^^^ -------------
@@ -47,6 +47,38 @@ help: use parentheses to construct a tuple
LL | two_ints((1, 2));
| + +
-error: aborting due to 4 previous errors
+error[E0061]: this function takes 1 argument but 2 arguments were supplied
+ --> $DIR/args-instead-of-tuple.rs:16:5
+ |
+LL | with_generic(3, 4);
+ | ^^^^^^^^^^^^ - - supplied 2 arguments
+ |
+note: function defined here
+ --> $DIR/args-instead-of-tuple.rs:22:4
+ |
+LL | fn with_generic<T: Copy + Send>((a, b): (i32, T)) {
+ | ^^^^^^^^^^^^ ----------------
+help: use parentheses to construct a tuple
+ |
+LL | with_generic((3, 4));
+ | + +
+
+error[E0061]: this function takes 1 argument but 2 arguments were supplied
+ --> $DIR/args-instead-of-tuple.rs:25:9
+ |
+LL | with_generic(a, b);
+ | ^^^^^^^^^^^^ - - supplied 2 arguments
+ |
+note: function defined here
+ --> $DIR/args-instead-of-tuple.rs:22:4
+ |
+LL | fn with_generic<T: Copy + Send>((a, b): (i32, T)) {
+ | ^^^^^^^^^^^^ ----------------
+help: use parentheses to construct a tuple
+ |
+LL | with_generic((a, b));
+ | + +
+
+error: aborting due to 6 previous errors
For more information about this error, try `rustc --explain E0061`.
From a8bac9879a36d01c1fc325ed85d6a992deab88fa Mon Sep 17 00:00:00 2001
From: Rob Pilling <robpilling@gmail.com>
Date: Sun, 16 Jan 2022 22:47:33 +0000
Subject: [PATCH 5/5] Remove 1-tuple unreachable case
---
.../rustc_typeck/src/check/fn_ctxt/checks.rs | 30 +++++++------------
.../args-instead-of-tuple-errors.rs | 3 ++
.../args-instead-of-tuple-errors.stderr | 12 ++++++--
3 files changed, 24 insertions(+), 21 deletions(-)
diff --git a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
index af0c9e5e5090e..d7022c27d3984 100644
--- a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
+++ b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs
@@ -28,9 +28,9 @@ use crate::structured_errors::StructuredDiagnostic;
use std::iter;
use std::slice;
-enum FnArgsAsTuple<'hir> {
- Single(&'hir hir::Expr<'hir>),
- Multi { first: &'hir hir::Expr<'hir>, last: &'hir hir::Expr<'hir> },
+struct FnArgsAsTuple<'hir> {
+ first: &'hir hir::Expr<'hir>,
+ last: &'hir hir::Expr<'hir>,
}
impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
@@ -432,23 +432,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
String::from("()"),
Applicability::MachineApplicable,
);
- } else if let Some(tuple_fn_arg) = sugg_tuple_wrap_args {
- use FnArgsAsTuple::*;
-
- let spans = match tuple_fn_arg {
- Multi { first, last } => vec![
+ } else if let Some(FnArgsAsTuple { first, last }) = sugg_tuple_wrap_args {
+ err.multipart_suggestion(
+ "use parentheses to construct a tuple",
+ vec![
(first.span.shrink_to_lo(), '('.to_string()),
(last.span.shrink_to_hi(), ')'.to_string()),
],
- Single(single) => vec![
- (single.span.shrink_to_lo(), '('.to_string()),
- (single.span.shrink_to_hi(), ",)".to_string()),
- ],
- };
-
- err.multipart_suggestion(
- "use parentheses to construct a tuple",
- spans,
Applicability::MachineApplicable,
);
} else {
@@ -519,8 +509,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
if all_match {
match provided_args {
[] => None,
- [single] => Some(FnArgsAsTuple::Single(single)),
- [first, .., last] => Some(FnArgsAsTuple::Multi { first, last }),
+ [_] => unreachable!(
+ "shouldn't reach here - need count mismatch between 1-tuple and 1-argument"
+ ),
+ [first, .., last] => Some(FnArgsAsTuple { first, last }),
}
} else {
None
diff --git a/src/test/ui/suggestions/args-instead-of-tuple-errors.rs b/src/test/ui/suggestions/args-instead-of-tuple-errors.rs
index c4e9c68e219e6..2c3ee5fcb8039 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple-errors.rs
+++ b/src/test/ui/suggestions/args-instead-of-tuple-errors.rs
@@ -7,6 +7,9 @@ fn main() {
//~^ ERROR this enum variant takes 1 argument but 2 arguments were supplied
int_bool(1, 2);
//~^ ERROR this function takes 1 argument but 2 arguments were supplied
+
+ let _: Option<(i8,)> = Some();
+ //~^ ERROR this enum variant takes 1 argument but 0 arguments were supplied
}
fn int_bool(_: (i32, bool)) {
diff --git a/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr b/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr
index c53c8bbdcc9df..a2ad602dbd47a 100644
--- a/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr
+++ b/src/test/ui/suggestions/args-instead-of-tuple-errors.stderr
@@ -15,11 +15,19 @@ LL | int_bool(1, 2);
| expected 1 argument
|
note: function defined here
- --> $DIR/args-instead-of-tuple-errors.rs:12:4
+ --> $DIR/args-instead-of-tuple-errors.rs:15:4
|
LL | fn int_bool(_: (i32, bool)) {
| ^^^^^^^^ --------------
-error: aborting due to 2 previous errors
+error[E0061]: this enum variant takes 1 argument but 0 arguments were supplied
+ --> $DIR/args-instead-of-tuple-errors.rs:11:28
+ |
+LL | let _: Option<(i8,)> = Some();
+ | ^^^^-- supplied 0 arguments
+ | |
+ | expected 1 argument
+
+error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0061`.