Tweak move error

[estebank]

Point at method definition that causes type to be consumed.

Fix #94056.

[rust-highfive]

r? @davidtwco

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[estebank]

Before

error[E0507]: cannot move out of `abc`, a captured variable in an `FnMut` closure
 --> f33.rs:3:34
  |
2 |     let mut abc = Abc { bar: Vec::new() };
  |         ------- captured outer variable
3 |     items.iter().for_each(|item| abc.update(*item));
  |                           -------^^^--------------
  |                           |      |
  |                           |      move occurs because `abc` has type `Abc`, which does not implement the `Copy` trait
  |                           captured by this `FnMut` closure

warning: variable does not need to be mutable
 --> f33.rs:2:9
  |
2 |     let mut abc = Abc { bar: Vec::new() };
  |         ----^^^
  |         |
  |         help: remove this `mut`
  |
  = note: `#[warn(unused_mut)]` on by default

error[E0382]: use of moved value: `abc`
 --> f33.rs:5:5
  |
2 |     let mut abc = Abc { bar: Vec::new() };
  |         ------- move occurs because `abc` has type `Abc`, which does not implement the `Copy` trait
3 |     items.iter().for_each(|item| abc.update(*item));
  |                           ------ --- variable moved due to use in closure
  |                           |
  |                           value moved into closure here
4 |     //~^ ERROR cannot move out of `abc`, a captured variable in an `FnMut` closure
5 |     abc //~ ERROR use of moved value: `abc`
  |     ^^^ value used here after move

After

error[E0507]: cannot move out of `abc`, a captured variable in an `FnMut` closure
  --> f33.rs:3:34
   |
2  |     let mut abc = Abc { bar: Vec::new() };
   |         ------- captured outer variable
3  |     items.iter().for_each(|item| abc.update(*item));
   |                           -------^^^--------------
   |                           |      |   |
   |                           |      |   `abc` moved due to this method call
   |                           |      move occurs because `abc` has type `Abc`, which does not implement the `Copy` trait
   |                           captured by this `FnMut` closure
   |
note: this function takes ownership of the receiver `self`, which moves `abc`
  --> f33.rs:13:19
   |
13 |     fn update(mut self, bar: u64) {
   |                   ^^^^

warning: variable does not need to be mutable
 --> f33.rs:2:9
  |
2 |     let mut abc = Abc { bar: Vec::new() };
  |         ----^^^
  |         |
  |         help: remove this `mut`
  |
  = note: `#[warn(unused_mut)]` on by default

error[E0382]: use of moved value: `abc`
 --> f33.rs:5:5
  |
2 |     let mut abc = Abc { bar: Vec::new() };
  |         ------- move occurs because `abc` has type `Abc`, which does not implement the `Copy` trait
3 |     items.iter().for_each(|item| abc.update(*item));
  |                           ------ --- variable moved due to use in closure
  |                           |
  |                           value moved into closure here
4 |     //~^ ERROR cannot move out of `abc`, a captured variable in an `FnMut` closure
5 |     abc //~ ERROR use of moved value: `abc`
  |     ^^^ value used here after move

[davidtwco]

Apologies for the delay in reviewing.

[davidtwco]

@bors r+

[bors]

📌 Commit 9875277 has been approved by davidtwco

[bors]

⌛ Testing commit 9875277 with merge 10dccdc...

[bors]

☀️ Test successful - checks-actions
Approved by: davidtwco
Pushing 10dccdc to master...

[rust-timer]

Finished benchmarking commit (10dccdc): comparison url.

Summary: This benchmark run did not return any relevant results. 6 results were found to be statistically significant but too small to be relevant.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression