Account for bare tuples in field searching logic

When looking for the field names and types of a given type, account for tuples. This allows suggestions for incorrectly nested field accesses and field name typos to trigger as intended. Previously these suggestions only worked on `ty::Adt`, including tuple structs which are no different to tuples, so they should behave the same in suggestions.

```
error[E0599]: no method named `get_ref` found for tuple `(BufReader<File>,)` in the current scope
  --> $DIR/missing-field-access.rs:11:15
   |
LL |     let x = f.get_ref();
   |               ^^^^^^^ method not found in `(BufReader<File>,)`
   |
help: one of the expressions' fields has a method of the same name
   |
LL |     let x = f.0.get_ref();
   |               ++
```

4 files changed, 75 insertions, 0 deletions

diff --git a/tests/ui/tuple/index-invalid.stderr b/tests/ui/tuple/index-invalid.stderr
index ae2c275f52c..acc4134d1a6 100644
--- a/tests/ui/tuple/index-invalid.stderr
+++ b/tests/ui/tuple/index-invalid.stderr
@@ -3,18 +3,32 @@ error[E0609]: no field `1` on type `(((),),)`
    |
 LL |     let _ = (((),),).1.0;
    |                      ^ unknown field
+   |
+help: a field with a similar name exists
+   |
+LL -     let _ = (((),),).1.0;
+LL +     let _ = (((),),).0.0;
+   |
 
 error[E0609]: no field `1` on type `((),)`
   --> $DIR/index-invalid.rs:4:24
    |
 LL |     let _ = (((),),).0.1;
    |                        ^ unknown field
+   |
+help: a field with a similar name exists
+   |
+LL -     let _ = (((),),).0.1;
+LL +     let _ = (((),),).0.0;
+   |
 
 error[E0609]: no field `000` on type `(((),),)`
   --> $DIR/index-invalid.rs:6:22
    |
 LL |     let _ = (((),),).000.000;
    |                      ^^^ unknown field
+   |
+   = note: available field is: `0`
 
 error: aborting due to 3 previous errors
 
diff --git a/tests/ui/tuple/missing-field-access.rs b/tests/ui/tuple/missing-field-access.rs
new file mode 100644
index 00000000000..4ccd759ccd2
--- /dev/null
+++ b/tests/ui/tuple/missing-field-access.rs
@@ -0,0 +1,17 @@
+use std::{fs::File, io::BufReader};
+
+struct F(BufReader<File>);
+
+fn main() {
+    let f = F(BufReader::new(File::open("x").unwrap()));
+    let x = f.get_ref(); //~ ERROR E0599
+    //~^ HELP one of the expressions' fields has a method of the same name
+    //~| HELP consider pinning the expression
+    let f = (BufReader::new(File::open("x").unwrap()), );
+    let x = f.get_ref(); //~ ERROR E0599
+    //~^ HELP one of the expressions' fields has a method of the same name
+    //~| HELP consider pinning the expression
+
+    // FIXME(estebank): the pinning suggestion should not be included in either case.
+    // https://github.com/rust-lang/rust/issues/144602
+}
diff --git a/tests/ui/tuple/missing-field-access.stderr b/tests/ui/tuple/missing-field-access.stderr
new file mode 100644
index 00000000000..711a8906d62
--- /dev/null
+++ b/tests/ui/tuple/missing-field-access.stderr
@@ -0,0 +1,38 @@
+error[E0599]: no method named `get_ref` found for struct `F` in the current scope
+  --> $DIR/missing-field-access.rs:7:15
+   |
+LL | struct F(BufReader<File>);
+   | -------- method `get_ref` not found for this struct
+...
+LL |     let x = f.get_ref();
+   |               ^^^^^^^ method not found in `F`
+   |
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let x = f.0.get_ref();
+   |               ++
+help: consider pinning the expression
+   |
+LL ~     let mut pinned = std::pin::pin!(f);
+LL ~     let x = pinned.as_ref().get_ref();
+   |
+
+error[E0599]: no method named `get_ref` found for tuple `(BufReader<File>,)` in the current scope
+  --> $DIR/missing-field-access.rs:11:15
+   |
+LL |     let x = f.get_ref();
+   |               ^^^^^^^ method not found in `(BufReader<File>,)`
+   |
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let x = f.0.get_ref();
+   |               ++
+help: consider pinning the expression
+   |
+LL ~     let mut pinned = std::pin::pin!(f);
+LL ~     let x = pinned.as_ref().get_ref();
+   |
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/tests/ui/tuple/tuple-index-out-of-bounds.stderr b/tests/ui/tuple/tuple-index-out-of-bounds.stderr
index 8b3c835c3e3..72827690909 100644
--- a/tests/ui/tuple/tuple-index-out-of-bounds.stderr
+++ b/tests/ui/tuple/tuple-index-out-of-bounds.stderr
@@ -15,6 +15,12 @@ error[E0609]: no field `2` on type `({integer}, {integer})`
    |
 LL |     tuple.2;
    |           ^ unknown field
+   |
+help: a field with a similar name exists
+   |
+LL -     tuple.2;
+LL +     tuple.0;
+   |
 
 error: aborting due to 2 previous errors