review comments: do not always point at init expr

estebank · estebank · commit 6b0cce4b5018 · 2023-01-05T16:51:16.000Z
diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs
@@ -355,6 +355,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 }
             }
         }
+        if span_labels.len() < 2 {
+            return false;
+        }
         for (sp, label) in span_labels {
             err.span_label(sp, &label);
         }
diff --git a/src/test/ui/argument-suggestions/two-mismatch-notes.stderr b/src/test/ui/argument-suggestions/two-mismatch-notes.stderr
@@ -1,8 +1,6 @@
 error[E0308]: arguments to this function are incorrect
   --> $DIR/two-mismatch-notes.rs:10:5
    |
-LL |     let w = Wrapper::<isize>(1isize);
-   |             ------------------------ here the type of `w` is inferred to be `Wrapper<isize>`
 LL |     foo(f, w);
    |     ^^^
    |
diff --git a/src/test/ui/async-await/dont-suggest-missing-await.stderr b/src/test/ui/async-await/dont-suggest-missing-await.stderr
@@ -1,8 +1,6 @@
 error[E0308]: mismatched types
   --> $DIR/dont-suggest-missing-await.rs:14:18
    |
-LL |         let x = make_u32();
-   |                 ---------- here the type of `x` is inferred to be `impl Future<Output = u32>`
 LL |         take_u32(x)
    |         -------- ^ expected `u32`, found opaque type
    |         |
diff --git a/src/test/ui/async-await/suggest-missing-await-closure.stderr b/src/test/ui/async-await/suggest-missing-await-closure.stderr
@@ -1,8 +1,6 @@
 error[E0308]: mismatched types
   --> $DIR/suggest-missing-await-closure.rs:16:18
    |
-LL |         let x = make_u32();
-   |                 ---------- here the type of `x` is inferred to be `impl Future<Output = u32>`
 LL |         take_u32(x)
    |         -------- ^ expected `u32`, found opaque type
    |         |
diff --git a/src/test/ui/async-await/suggest-missing-await.stderr b/src/test/ui/async-await/suggest-missing-await.stderr
@@ -1,8 +1,6 @@
 error[E0308]: mismatched types
   --> $DIR/suggest-missing-await.rs:12:14
    |
-LL |     let x = make_u32();
-   |             ---------- here the type of `x` is inferred to be `impl Future<Output = u32>`
 LL |     take_u32(x)
    |     -------- ^ expected `u32`, found opaque type
    |     |
diff --git a/src/test/ui/closures/closure-return-type-mismatch.stderr b/src/test/ui/closures/closure-return-type-mismatch.stderr
@@ -1,8 +1,6 @@
 error[E0308]: mismatched types
   --> $DIR/closure-return-type-mismatch.rs:7:9
    |
-LL |         let a = true;
-   |                 ---- here the type of `a` is inferred to be `bool`
 LL |         a
    |         ^ expected `&str`, found `bool`
    |
diff --git a/src/test/ui/coercion/coerce-to-bang.stderr b/src/test/ui/coercion/coerce-to-bang.stderr
@@ -33,9 +33,6 @@ LL | fn foo(x: usize, y: !, z: usize) { }
 error[E0308]: mismatched types
   --> $DIR/coerce-to-bang.rs:26:12
    |
-LL |     let b = 22;
-   |             -- here the type of `b` is inferred to be `{integer}`
-LL |     let c = 44;
 LL |     foo(a, b, c); // ... and hence a reference to `a` is expected to diverge.
    |     ---    ^ expected `!`, found integer
    |     |
@@ -52,9 +49,6 @@ LL | fn foo(x: usize, y: !, z: usize) { }
 error[E0308]: mismatched types
   --> $DIR/coerce-to-bang.rs:36:12
    |
-LL |     let b = 22;
-   |             -- here the type of `b` is inferred to be `{integer}`
-LL |     let c = 44;
 LL |     foo(a, b, c);
    |     ---    ^ expected `!`, found integer
    |     |
@@ -71,9 +65,6 @@ LL | fn foo(x: usize, y: !, z: usize) { }
 error[E0308]: mismatched types
   --> $DIR/coerce-to-bang.rs:45:12
    |
-LL |     let b = 22;
-   |             -- here the type of `b` is inferred to be `{integer}`
-LL |     let c = 44;
 LL |     foo(a, b, c);
    |     ---    ^ expected `!`, found integer
    |     |
diff --git a/src/test/ui/generic-associated-types/collections-project-default.stderr b/src/test/ui/generic-associated-types/collections-project-default.stderr
@@ -4,9 +4,6 @@ error[E0308]: mismatched types
 LL | fn floatify_sibling<C>(ints: &C) -> <C as Collection<i32>>::Sibling<f32>
    |                                     ------------------------------------ expected `<C as Collection<i32>>::Sibling<f32>` because of return type
 ...
-LL |     let mut res = <C::Family as CollectionFamily>::Member::<f32>::empty();
-   |                   ------------------------------------------------------- here the type of `res` is inferred to be `<<C as Collection<i32>>::Family as CollectionFamily>::Member<f32>`
-...
 LL |     res
    |     ^^^ expected Collection::Sibling, found CollectionFamily::Member
    |
diff --git a/src/test/ui/issues/issue-15783.stderr b/src/test/ui/issues/issue-15783.stderr
@@ -1,8 +1,6 @@
 error[E0308]: mismatched types
   --> $DIR/issue-15783.rs:8:19
    |
-LL |     let x = Some(&[name]);
-   |             ------------- here the type of `x` is inferred to be `Option<&[&str; 1]>`
 LL |     let msg = foo(x);
    |               --- ^ expected slice `[&str]`, found array `[&str; 1]`
    |               |
diff --git a/src/test/ui/let-else/let-else-ref-bindings.stderr b/src/test/ui/let-else/let-else-ref-bindings.stderr
@@ -19,9 +19,6 @@ LL |     let Some(ref a): Option<&[u8]> = &some else { return };
 error[E0308]: mismatched types
   --> $DIR/let-else-ref-bindings.rs:24:34
    |
-LL |     let some = Some(bytes);
-   |                ----------- here the type of `some` is inferred to be `Option<Vec<u8>>`
-...
 LL |     let Some(a): Option<&[u8]> = some else { return };
    |                  -------------   ^^^^ expected `&[u8]`, found struct `Vec`
    |                  |
@@ -62,9 +59,6 @@ LL |     let Some(ref mut a): Option<&mut [u8]> = &mut some else { return };
 error[E0308]: mismatched types
   --> $DIR/let-else-ref-bindings.rs:52:38
    |
-LL |     let mut some = Some(bytes);
-   |                    ----------- here the type of `some` is inferred to be `Option<Vec<u8>>`
-...
 LL |     let Some(a): Option<&mut [u8]> = some else { return };
    |                  -----------------   ^^^^ expected `&mut [u8]`, found struct `Vec`
    |                  |
diff --git a/src/test/ui/methods/method-deref-to-same-trait-object-with-separate-params.stderr b/src/test/ui/methods/method-deref-to-same-trait-object-with-separate-params.stderr
@@ -10,9 +10,6 @@ LL | #![feature(unsized_locals, unsized_fn_params)]
 error[E0308]: mismatched types
   --> $DIR/method-deref-to-same-trait-object-with-separate-params.rs:87:24
    |
-LL |     let z = x.foo();
-   |             ------- here the type of `z` is inferred to be `u32`
-...
 LL |     let _seetype: () = z;
    |                   --   ^ expected `()`, found `u32`
    |                   |
@@ -21,9 +18,6 @@ LL |     let _seetype: () = z;
 error[E0308]: mismatched types
   --> $DIR/method-deref-to-same-trait-object-with-separate-params.rs:104:24
    |
-LL |     let z = x.foo();
-   |             ------- here the type of `z` is inferred to be `u64`
-...
 LL |     let _seetype: () = z;
    |                   --   ^ expected `()`, found `u64`
    |                   |
@@ -66,9 +60,6 @@ LL |     let z = FinalFoo::foo(x);
 error[E0308]: mismatched types
   --> $DIR/method-deref-to-same-trait-object-with-separate-params.rs:139:24
    |
-LL |     let z = x.foo();
-   |             ------- here the type of `z` is inferred to be `u8`
-...
 LL |     let _seetype: () = z;
    |                   --   ^ expected `()`, found `u8`
    |                   |
@@ -77,9 +68,6 @@ LL |     let _seetype: () = z;
 error[E0308]: mismatched types
   --> $DIR/method-deref-to-same-trait-object-with-separate-params.rs:157:24
    |
-LL |     let z = x.foo();
-   |             ------- here the type of `z` is inferred to be `u32`
-...
 LL |     let _seetype: () = z;
    |                   --   ^ expected `()`, found `u32`
    |                   |
@@ -88,9 +76,6 @@ LL |     let _seetype: () = z;
 error[E0308]: mismatched types
   --> $DIR/method-deref-to-same-trait-object-with-separate-params.rs:174:24
    |
-LL |     let z = x.foo();
-   |             ------- here the type of `z` is inferred to be `u32`
-...
 LL |     let _seetype: () = z;
    |                   --   ^ expected `()`, found `u32`
    |                   |
diff --git a/src/test/ui/mismatched_types/abridged.stderr b/src/test/ui/mismatched_types/abridged.stderr
@@ -53,39 +53,23 @@ LL |     Ok(Foo { bar: 1 })
 error[E0308]: mismatched types
   --> $DIR/abridged.rs:39:5
    |
-LL |   fn d() -> X<X<String, String>, String> {
-   |             ---------------------------- expected `X<X<String, String>, String>` because of return type
-LL |       let x = X {
-   |  _____________-
-LL | |         x: X {
-LL | |             x: "".to_string(),
-LL | |             y: 2,
-LL | |         },
-LL | |         y: 3,
-LL | |     };
-   | |_____- here the type of `x` is inferred to be `X<X<String, {integer}>, {integer}>`
-LL |       x
-   |       ^ expected struct `String`, found integer
+LL | fn d() -> X<X<String, String>, String> {
+   |           ---------------------------- expected `X<X<String, String>, String>` because of return type
+...
+LL |     x
+   |     ^ expected struct `String`, found integer
    |
    = note: expected struct `X<X<_, String>, String>`
               found struct `X<X<_, {integer}>, {integer}>`
 
 error[E0308]: mismatched types
   --> $DIR/abridged.rs:50:5
    |
-LL |   fn e() -> X<X<String, String>, String> {
-   |             ---------------------------- expected `X<X<String, String>, String>` because of return type
-LL |       let x = X {
-   |  _____________-
-LL | |         x: X {
-LL | |             x: "".to_string(),
-LL | |             y: 2,
-LL | |         },
-LL | |         y: "".to_string(),
-LL | |     };
-   | |_____- here the type of `x` is inferred to be `X<X<String, {integer}>, String>`
-LL |       x
-   |       ^ expected struct `String`, found integer
+LL | fn e() -> X<X<String, String>, String> {
+   |           ---------------------------- expected `X<X<String, String>, String>` because of return type
+...
+LL |     x
+   |     ^ expected struct `String`, found integer
    |
    = note: expected struct `X<X<_, String>, _>`
               found struct `X<X<_, {integer}>, _>`
diff --git a/src/test/ui/parser/struct-literal-variant-in-if.stderr b/src/test/ui/parser/struct-literal-variant-in-if.stderr
@@ -51,8 +51,6 @@ LL |     if x == E::V { field } {}
 error[E0308]: mismatched types
   --> $DIR/struct-literal-variant-in-if.rs:10:20
    |
-LL |     let field = true;
-   |                 ---- here the type of `field` is inferred to be `bool`
 LL |     if x == E::V { field } {}
    |     ---------------^^^^^--
    |     |              |
diff --git a/src/test/ui/rfc-2497-if-let-chains/ensure-that-let-else-does-not-interact-with-let-chains.stderr b/src/test/ui/rfc-2497-if-let-chains/ensure-that-let-else-does-not-interact-with-let-chains.stderr
@@ -100,9 +100,6 @@ LL |     let Some(n) = opt && let another = n else {
 error[E0308]: mismatched types
   --> $DIR/ensure-that-let-else-does-not-interact-with-let-chains.rs:9:19
    |
-LL |     let opt = Some(1i32);
-   |               ---------- here the type of `opt` is inferred to be `Option<i32>`
-...
 LL |     let Some(n) = opt && n == 1 else {
    |                   ^^^ expected `bool`, found enum `Option`
    |
@@ -123,9 +120,6 @@ LL |     let Some(n) = opt && n == 1 else {
 error[E0308]: mismatched types
   --> $DIR/ensure-that-let-else-does-not-interact-with-let-chains.rs:15:19
    |
-LL |     let opt = Some(1i32);
-   |               ---------- here the type of `opt` is inferred to be `Option<i32>`
-...
 LL |     let Some(n) = opt && let another = n else {
    |                   ^^^ expected `bool`, found enum `Option`
    |
diff --git a/src/test/ui/structs/struct-base-wrong-type.stderr b/src/test/ui/structs/struct-base-wrong-type.stderr
@@ -13,8 +13,6 @@ LL | static foo_i: Foo = Foo { a: 2, ..4 };
 error[E0308]: mismatched types
   --> $DIR/struct-base-wrong-type.rs:12:27
    |
-LL |     let b = Bar { x: 5 };
-   |             ------------ here the type of `b` is inferred to be `Bar`
 LL |     let f = Foo { a: 2, ..b };
    |                           ^ expected struct `Foo`, found struct `Bar`
 
diff --git a/src/test/ui/suggestions/call-boxed.stderr b/src/test/ui/suggestions/call-boxed.stderr
@@ -4,10 +4,7 @@ error[E0308]: mismatched types
 LL |     let mut x = 1i32;
    |                 ---- expected due to this value
 LL |     let y = Box::new(|| 1);
-   |             --------------
-   |             |        |
-   |             |        the found closure
-   |             here the type of `y` is inferred to be `Box<[closure@call-boxed.rs:3:22]>`
+   |                      -- the found closure
 LL |     x = y;
    |         ^ expected `i32`, found struct `Box`
    |
diff --git a/src/test/ui/suggestions/issue-86100-tuple-paren-comma.stderr b/src/test/ui/suggestions/issue-86100-tuple-paren-comma.stderr
@@ -49,8 +49,6 @@ LL |     let _s = S { _s: ("abc".to_string(),) };
 error[E0308]: mismatched types
   --> $DIR/issue-86100-tuple-paren-comma.rs:23:22
    |
-LL |     let t = (1, 2);
-   |             ------ here the type of `t` is inferred to be `({integer}, {integer})`
 LL |     let _x: (i32,) = (t);
    |             ------   ^^^ expected a tuple with 1 element, found one with 2 elements
    |             |
diff --git a/src/test/ui/traits/issue-52893.stderr b/src/test/ui/traits/issue-52893.stderr
@@ -4,8 +4,6 @@ error[E0308]: mismatched types
 LL | impl<F, Name, P> AddClass<Name, F> for Class<P>
    |      - this type parameter
 ...
-LL |         let output = builder.to_ref();
-   |                      ---------------- here the type of `output` is inferred to be `Class<P>`
 LL |         builder.push(output);
    |                 ---- ^^^^^^ expected type parameter `F`, found struct `Class`
    |                 |
diff --git a/src/test/ui/tuple/wrong_argument_ice-3.stderr b/src/test/ui/tuple/wrong_argument_ice-3.stderr
@@ -1,9 +1,6 @@
 error[E0061]: this method takes 1 argument but 2 arguments were supplied
   --> $DIR/wrong_argument_ice-3.rs:9:16
    |
-LL |     let new_group = vec![String::new()];
-   |                     ------------------- here the type of `new_group` is inferred to be `Vec<String>`
-...
 LL |         groups.push(new_group, vec![process]);
    |                ^^^^            ------------- argument of type `Vec<&Process>` unexpected
    |
diff --git a/src/test/ui/type/type-mismatch-same-crate-name.stderr b/src/test/ui/type/type-mismatch-same-crate-name.stderr
@@ -1,9 +1,6 @@
 error[E0308]: mismatched types
   --> $DIR/type-mismatch-same-crate-name.rs:16:20
    |
-LL |     let foo2 = {extern crate crate_a2 as a; a::Foo};
-   |                ------------------------------------ here the type of `foo2` is inferred to be `Foo`
-...
 LL |         a::try_foo(foo2);
    |         ---------- ^^^^ expected struct `main::a::Foo`, found a different struct `main::a::Foo`
    |         |
@@ -30,9 +27,6 @@ LL | pub fn try_foo(x: Foo){}
 error[E0308]: mismatched types
   --> $DIR/type-mismatch-same-crate-name.rs:20:20
    |
-LL |     let bar2 = {extern crate crate_a2 as a; a::bar()};
-   |                -------------------------------------- here the type of `bar2` is inferred to be `Box<dyn Bar>`
-...
 LL |         a::try_bar(bar2);
    |         ---------- ^^^^ expected trait `main::a::Bar`, found a different trait `main::a::Bar`
    |         |

Original file line number	Diff line number	Diff line change
`@@ -355,6 +355,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {`
`355`	`355`	`}`
`356`	`356`	`}`
`357`	`357`	`}`
	`358`	`+ if span_labels.len() < 2 {`
	`359`	`+ return false;`
	`360`	`+ }`
`358`	`361`	`for (sp, label) in span_labels {`
`359`	`362`	`err.span_label(sp, &label);`
`360`	`363`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,6 @@`
`1`	`1`	`error[E0308]: arguments to this function are incorrect`
`2`	`2`	`--> $DIR/two-mismatch-notes.rs:10:5`
`3`	`3`	`\|`
`4`		`-LL \| let w = Wrapper::<isize>(1isize);`
`5`		- \| ------------------------ here the type of `w` is inferred to be `Wrapper<isize>`
`6`	`4`	`LL \| foo(f, w);`
`7`	`5`	`\| ^^^`
`8`	`6`	`\|`
Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,6 @@`
`1`	`1`	`error[E0308]: mismatched types`
`2`	`2`	`--> $DIR/dont-suggest-missing-await.rs:14:18`
`3`	`3`	`\|`
`4`		`-LL \| let x = make_u32();`
`5`		- \| ---------- here the type of `x` is inferred to be `impl Future<Output = u32>`
`6`	`4`	`LL \| take_u32(x)`
`7`	`5`	\| -------- ^ expected `u32`, found opaque type
`8`	`6`	`\| \|`
Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,6 @@`
`1`	`1`	`error[E0308]: mismatched types`
`2`	`2`	`--> $DIR/suggest-missing-await-closure.rs:16:18`
`3`	`3`	`\|`
`4`		`-LL \| let x = make_u32();`
`5`		- \| ---------- here the type of `x` is inferred to be `impl Future<Output = u32>`
`6`	`4`	`LL \| take_u32(x)`
`7`	`5`	\| -------- ^ expected `u32`, found opaque type
`8`	`6`	`\| \|`
Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,6 @@`
`1`	`1`	`error[E0308]: mismatched types`
`2`	`2`	`--> $DIR/suggest-missing-await.rs:12:14`
`3`	`3`	`\|`
`4`		`-LL \| let x = make_u32();`
`5`		- \| ---------- here the type of `x` is inferred to be `impl Future<Output = u32>`
`6`	`4`	`LL \| take_u32(x)`
`7`	`5`	\| -------- ^ expected `u32`, found opaque type
`8`	`6`	`\| \|`
Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,6 @@`
`1`	`1`	`error[E0308]: mismatched types`
`2`	`2`	`--> $DIR/closure-return-type-mismatch.rs:7:9`
`3`	`3`	`\|`
`4`		`-LL \| let a = true;`
`5`		- \| ---- here the type of `a` is inferred to be `bool`
`6`	`4`	`LL \| a`
`7`	`5`	\| ^ expected `&str`, found `bool`
`8`	`6`	`\|`
Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,6 @@`
`1`	`1`	`error[E0308]: mismatched types`
`2`	`2`	`--> $DIR/issue-15783.rs:8:19`
`3`	`3`	`\|`
`4`		`-LL \| let x = Some(&[name]);`
`5`		- \| ------------- here the type of `x` is inferred to be `Option<&[&str; 1]>`
`6`	`4`	`LL \| let msg = foo(x);`
`7`	`5`	\| --- ^ expected slice `[&str]`, found array `[&str; 1]`
`8`	`6`	`\| \|`