Use `fn` ptr signature instead of `{closure@..}` in infer error

When suggesting a type on inference error, do not use `{closure@..}`.
Instead, replace with an appropriate `fn` ptr.

On the error message, use `short_ty_string` and write long types to
disk.

```
error[E0284]: type annotations needed for `Select<{closure@lib.rs:2782:13}, _, Expression<'_>, _>`
  --> crates/lang/src/parser.rs:41:13
   |
41 |         let lit = select! {
   |             ^^^
42 |             Token::Int(i) = e => Expression::new(Expr::Lit(ast::Lit::Int(i.parse().unwrap())), e.span()),
   |                                                                                                  ---- type must be known at this point
   |
   = note: the full type name has been written to '/home/gh-estebank/iowo/target/debug/deps/lang-e2d6e25819442273.long-type-4587393693885174369.txt'
   = note: cannot satisfy `<_ as chumsky::input::Input<'_>>::Span == SimpleSpan`
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
   |
41 |         let lit: Select<for<'a, 'b> fn(tokens::Token<'_>, &'a mut MapExtra<'_, 'b, _, _>) -> Option<Expression<'_>>, _, Expression<'_>, _> = select! {
   |                +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
```

instead of

```
error[E0284]: type annotations needed for `Select<{closure@/home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/chumsky-1.0.0-alpha.6/src/lib.rs:2782:13: 2782:28}, _, Expression<'_>, _>`
  --> crates/lang/src/parser.rs:41:13
   |
41 |         let lit = select! {
   |             ^^^
42 |             Token::Int(i) = e => Expression::new(Expr::Lit(ast::Lit::Int(i.parse().unwrap())), e.span()),
   |                                                                                                  ---- type must be known at this point
   |
   = note: cannot satisfy `<_ as chumsky::input::Input<'_>>::Span == SimpleSpan`
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
   |
41 |         let lit: Select<{closure@/home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/chumsky-1.0.0-alpha.6/src/lib.rs:2782:13: 2782:28}, _, Expression<'_>, _> = select! {
   |                ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
```

Fix #123630.

5 files changed, 5 insertions, 5 deletions

diff --git a/tests/ui/issues/issue-12187-1.stderr b/tests/ui/issues/issue-12187-1.stderr
index 93dc1df8f63..704854fe585 100644
--- a/tests/ui/issues/issue-12187-1.stderr
+++ b/tests/ui/issues/issue-12187-1.stderr
@@ -1,4 +1,4 @@
-error[E0282]: type annotations needed for `&T`
+error[E0282]: type annotations needed for `&_`
   --> $DIR/issue-12187-1.rs:6:9
    |
 LL |     let &v = new();
diff --git a/tests/ui/issues/issue-12187-2.stderr b/tests/ui/issues/issue-12187-2.stderr
index e9ba52ff4fd..eeef63a1d0b 100644
--- a/tests/ui/issues/issue-12187-2.stderr
+++ b/tests/ui/issues/issue-12187-2.stderr
@@ -1,4 +1,4 @@
-error[E0282]: type annotations needed for `&T`
+error[E0282]: type annotations needed for `&_`
   --> $DIR/issue-12187-2.rs:6:9
    |
 LL |     let &v = new();
diff --git a/tests/ui/issues/issue-17551.stderr b/tests/ui/issues/issue-17551.stderr
index 68f54a31084..b9cb76fc298 100644
--- a/tests/ui/issues/issue-17551.stderr
+++ b/tests/ui/issues/issue-17551.stderr
@@ -1,4 +1,4 @@
-error[E0282]: type annotations needed for `B<T>`
+error[E0282]: type annotations needed for `B<_>`
   --> $DIR/issue-17551.rs:6:9
    |
 LL |     let foo = B(marker::PhantomData);
diff --git a/tests/ui/issues/issue-23046.stderr b/tests/ui/issues/issue-23046.stderr
index b6e23814543..f70ac0c9f38 100644
--- a/tests/ui/issues/issue-23046.stderr
+++ b/tests/ui/issues/issue-23046.stderr
@@ -1,4 +1,4 @@
-error[E0282]: type annotations needed for `Expr<'_, VAR>`
+error[E0282]: type annotations needed for `Expr<'_, _>`
   --> $DIR/issue-23046.rs:17:15
    |
 LL |     let ex = |x| {
diff --git a/tests/ui/issues/issue-98299.stderr b/tests/ui/issues/issue-98299.stderr
index e99d8e5cc80..becf16d1db9 100644
--- a/tests/ui/issues/issue-98299.stderr
+++ b/tests/ui/issues/issue-98299.stderr
@@ -1,4 +1,4 @@
-error[E0282]: type annotations needed for `SmallCString<N>`
+error[E0282]: type annotations needed for `SmallCString<_>`
   --> $DIR/issue-98299.rs:4:36
    |
 LL |     SmallCString::try_from(p).map(|cstr| cstr);