Make E0599's label more clear for field which is used like a method.

fixes #127178

Author: surechen

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -2277,7 +2277,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     let call_expr = tcx.hir().expect_expr(tcx.parent_hir_id(expr.hir_id));
 
                     if let Some(span) = call_expr.span.trim_start(item_name.span) {
-                        err.span_suggestion(
+                        err.span_suggestion_verbose(
                             span,
                             "remove the arguments",
                             "",
@@ -3266,7 +3266,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 .copied();
 
             if explain {
-                err.help("items from traits can only be used if the trait is in scope");
+                err.help(
+                    "items from traits can only be used if the trait is implemented and in scope",
+                );
             }
 
             let msg = format!(
@@ -3570,7 +3572,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 }
             }
         }
-        if self.suggest_valid_traits(err, item_name, valid_out_of_scope_traits, true) {
+        if self.suggest_valid_traits(
+            err,
+            item_name,
+            valid_out_of_scope_traits,
+            !trait_missing_method,
+        ) {
             return;
         }
 
@@ -3680,7 +3687,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 _ => None,
             };
             if !trait_missing_method {
-                err.help(if param_type.is_some() {
+                err.span_help(span, if param_type.is_some() {
                     "items from traits can only be used if the type parameter is bounded by the trait"
                 } else {
                     "items from traits can only be used if the trait is implemented and in scope"

tests/ui/associated-consts/associated-const-no-item.stderr

@@ -4,7 +4,11 @@ error[E0599]: no associated item named `ID` found for type `i32` in the current
 LL | const X: i32 = <i32>::ID;
    |                       ^^ associated item not found in `i32`
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/associated-const-no-item.rs:5:23
+   |
+LL | const X: i32 = <i32>::ID;
+   |                       ^^
 note: `Foo` defines an item `ID`, perhaps you need to implement it
   --> $DIR/associated-const-no-item.rs:1:1
    |

tests/ui/async-await/in-trait/dont-project-to-specializable-projection.stderr

@@ -29,7 +29,7 @@ LL |         match fut.as_mut().poll(ctx) {
    |
    = note: the method is available for `Pin<&mut impl Future<Output = ()>>` here
    |
-   = help: items from traits can only be used if the trait is in scope
+   = help: items from traits can only be used if the trait is implemented and in scope
 help: trait `Future` which provides `poll` is implemented but not in scope; perhaps you want to import it
    |
 LL + use std::future::Future;

tests/ui/auto-ref-slice-plus-ref.stderr

@@ -4,7 +4,11 @@ error[E0599]: no method named `test_mut` found for struct `Vec<{integer}>` in th
 LL |     a.test_mut();
    |       ^^^^^^^^
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/auto-ref-slice-plus-ref.rs:7:7
+   |
+LL |     a.test_mut();
+   |       ^^^^^^^^
 note: `MyIter` defines an item `test_mut`, perhaps you need to implement it
   --> $DIR/auto-ref-slice-plus-ref.rs:14:1
    |
@@ -19,7 +23,11 @@ error[E0599]: no method named `test` found for struct `Vec<{integer}>` in the cu
 LL |     a.test();
    |       ^^^^ method not found in `Vec<{integer}>`
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/auto-ref-slice-plus-ref.rs:8:7
+   |
+LL |     a.test();
+   |       ^^^^
 note: `MyIter` defines an item `test`, perhaps you need to implement it
   --> $DIR/auto-ref-slice-plus-ref.rs:14:1
    |
@@ -32,7 +40,11 @@ error[E0599]: no method named `test` found for array `[{integer}; 1]` in the cur
 LL |     ([1]).test();
    |           ^^^^ method not found in `[{integer}; 1]`
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/auto-ref-slice-plus-ref.rs:10:11
+   |
+LL |     ([1]).test();
+   |           ^^^^
 note: `MyIter` defines an item `test`, perhaps you need to implement it
   --> $DIR/auto-ref-slice-plus-ref.rs:14:1
    |
@@ -45,7 +57,11 @@ error[E0599]: no method named `test` found for reference `&[{integer}; 1]` in th
 LL |     (&[1]).test();
    |            ^^^^ method not found in `&[{integer}; 1]`
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/auto-ref-slice-plus-ref.rs:11:12
+   |
+LL |     (&[1]).test();
+   |            ^^^^
 note: `MyIter` defines an item `test`, perhaps you need to implement it
   --> $DIR/auto-ref-slice-plus-ref.rs:14:1
    |

tests/ui/box/unit/unique-object-noncopyable.stderr

@@ -12,7 +12,11 @@ LL |     let _z = y.clone();
            which is required by `Box<dyn Foo>: Clone`
            `dyn Foo: Clone`
            which is required by `Box<dyn Foo>: Clone`
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/unique-object-noncopyable.rs:24:16
+   |
+LL |     let _z = y.clone();
+   |                ^^^^^
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
 

tests/ui/coherence/coherence_inherent.stderr

@@ -4,7 +4,7 @@ error[E0599]: no method named `the_fn` found for reference `&TheStruct` in the c
 LL |         s.the_fn();
    |           ^^^^^^ method not found in `&TheStruct`
    |
-   = help: items from traits can only be used if the trait is in scope
+   = help: items from traits can only be used if the trait is implemented and in scope
 help: trait `TheTrait` which provides `the_fn` is implemented but not in scope; perhaps you want to import it
    |
 LL +     use Lib::TheTrait;

tests/ui/coherence/coherence_inherent_cc.stderr

@@ -4,7 +4,7 @@ error[E0599]: no method named `the_fn` found for reference `&TheStruct` in the c
 LL |         s.the_fn();
    |           ^^^^^^ method not found in `&TheStruct`
    |
-   = help: items from traits can only be used if the trait is in scope
+   = help: items from traits can only be used if the trait is implemented and in scope
 help: trait `TheTrait` which provides `the_fn` is implemented but not in scope; perhaps you want to import it
    |
 LL +     use coherence_inherent_cc_lib::TheTrait;

tests/ui/confuse-field-and-method/issue-2392.stderr

@@ -19,9 +19,13 @@ LL | struct Obj<F> where F: FnOnce() -> u32 {
    | ------------- method `not_closure` not found for this struct
 ...
 LL |     o_closure.not_closure();
-   |               ^^^^^^^^^^^-- help: remove the arguments
-   |               |
-   |               field, not a method
+   |               ^^^^^^^^^^^ field, not a method
+   |
+help: remove the arguments
+   |
+LL -     o_closure.not_closure();
+LL +     o_closure.not_closure;
+   |
 
 error[E0599]: no method named `closure` found for struct `Obj` in the current scope
   --> $DIR/issue-2392.rs:42:12
@@ -86,9 +90,13 @@ LL | struct Obj<F> where F: FnOnce() -> u32 {
    | ------------- method `not_closure` not found for this struct
 ...
 LL |     w.wrap.not_closure();
-   |            ^^^^^^^^^^^-- help: remove the arguments
-   |            |
-   |            field, not a method
+   |            ^^^^^^^^^^^ field, not a method
+   |
+help: remove the arguments
+   |
+LL -     w.wrap.not_closure();
+LL +     w.wrap.not_closure;
+   |
 
 error[E0599]: no method named `closure` found for struct `Obj` in the current scope
   --> $DIR/issue-2392.rs:58:24

tests/ui/copy-a-resource.stderr

@@ -7,7 +7,11 @@ LL | struct Foo {
 LL |     let _y = x.clone();
    |                ^^^^^ method not found in `Foo`
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/copy-a-resource.rs:18:16
+   |
+LL |     let _y = x.clone();
+   |                ^^^^^
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
 

tests/ui/functions-closures/fn-help-with-err.stderr

@@ -10,7 +10,11 @@ error[E0599]: no method named `bar` found for struct `Arc<{closure@$DIR/fn-help-
 LL |     arc2.bar();
    |          ^^^ method not found in `Arc<{closure@fn-help-with-err.rs:18:36}>`
    |
-   = help: items from traits can only be used if the trait is implemented and in scope
+help: items from traits can only be used if the trait is implemented and in scope
+  --> $DIR/fn-help-with-err.rs:19:10
+   |
+LL |     arc2.bar();
+   |          ^^^
 note: `Bar` defines an item `bar`, perhaps you need to implement it
   --> $DIR/fn-help-with-err.rs:5:1
    |