Rollup merge of #133087 - estebank:stmt-misparse, r=chenyukang

Detect missing `.` in method chain in `let` bindings and statements

On parse errors where an ident is found where one wasn't expected, see if the next elements might have been meant as method call or field access.

```
error: expected one of `.`, `;`, `?`, `else`, or an operator, found `map`
  --> $DIR/missing-dot-on-statement-expression.rs:7:29
   |
LL |     let _ = [1, 2, 3].iter()map(|x| x);
   |                             ^^^ expected one of `.`, `;`, `?`, `else`, or an operator
   |
help: you might have meant to write a method call
   |
LL |     let _ = [1, 2, 3].iter().map(|x| x);
   |                             +
```

4 files changed, 107 insertions, 0 deletions

diff --git a/tests/ui/parser/recover/missing-dot-on-statement-expression.fixed b/tests/ui/parser/recover/missing-dot-on-statement-expression.fixed
new file mode 100644
index 00000000000..1be4485b474
--- /dev/null
+++ b/tests/ui/parser/recover/missing-dot-on-statement-expression.fixed
@@ -0,0 +1,28 @@
+//@ run-rustfix
+#![allow(unused_must_use, dead_code)]
+struct S {
+    field: (),
+}
+fn main() {
+    let _ = [1, 2, 3].iter().map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `else`, or an operator, found `map`
+    //~^ HELP you might have meant to write a method call
+}
+fn foo() {
+    let baz = S {
+        field: ()
+    };
+    let _ = baz.field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `field`
+    //~^ HELP you might have meant to write a field
+}
+
+fn bar() {
+    [1, 2, 3].iter().map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `map`
+    //~^ HELP you might have meant to write a method call
+}
+fn baz() {
+    let baz = S {
+        field: ()
+    };
+    baz.field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `field`
+    //~^ HELP you might have meant to write a field
+}
diff --git a/tests/ui/parser/recover/missing-dot-on-statement-expression.rs b/tests/ui/parser/recover/missing-dot-on-statement-expression.rs
new file mode 100644
index 00000000000..5e2b545f414
--- /dev/null
+++ b/tests/ui/parser/recover/missing-dot-on-statement-expression.rs
@@ -0,0 +1,28 @@
+//@ run-rustfix
+#![allow(unused_must_use, dead_code)]
+struct S {
+    field: (),
+}
+fn main() {
+    let _ = [1, 2, 3].iter()map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `else`, or an operator, found `map`
+    //~^ HELP you might have meant to write a method call
+}
+fn foo() {
+    let baz = S {
+        field: ()
+    };
+    let _ = baz field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `field`
+    //~^ HELP you might have meant to write a field
+}
+
+fn bar() {
+    [1, 2, 3].iter()map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `map`
+    //~^ HELP you might have meant to write a method call
+}
+fn baz() {
+    let baz = S {
+        field: ()
+    };
+    baz field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `field`
+    //~^ HELP you might have meant to write a field
+}
diff --git a/tests/ui/parser/recover/missing-dot-on-statement-expression.stderr b/tests/ui/parser/recover/missing-dot-on-statement-expression.stderr
new file mode 100644
index 00000000000..a04d8bd34e2
--- /dev/null
+++ b/tests/ui/parser/recover/missing-dot-on-statement-expression.stderr
@@ -0,0 +1,46 @@
+error: expected one of `.`, `;`, `?`, `else`, or an operator, found `map`
+  --> $DIR/missing-dot-on-statement-expression.rs:7:29
+   |
+LL |     let _ = [1, 2, 3].iter()map(|x| x);
+   |                             ^^^ expected one of `.`, `;`, `?`, `else`, or an operator
+   |
+help: you might have meant to write a method call
+   |
+LL |     let _ = [1, 2, 3].iter().map(|x| x);
+   |                             +
+
+error: expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `field`
+  --> $DIR/missing-dot-on-statement-expression.rs:14:17
+   |
+LL |     let _ = baz field;
+   |                 ^^^^^ expected one of 8 possible tokens
+   |
+help: you might have meant to write a field access
+   |
+LL |     let _ = baz.field;
+   |                +
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found `map`
+  --> $DIR/missing-dot-on-statement-expression.rs:19:21
+   |
+LL |     [1, 2, 3].iter()map(|x| x);
+   |                     ^^^ expected one of `.`, `;`, `?`, `}`, or an operator
+   |
+help: you might have meant to write a method call
+   |
+LL |     [1, 2, 3].iter().map(|x| x);
+   |                     +
+
+error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `field`
+  --> $DIR/missing-dot-on-statement-expression.rs:26:9
+   |
+LL |     baz field;
+   |         ^^^^^ expected one of 8 possible tokens
+   |
+help: you might have meant to write a field access
+   |
+LL |     baz.field;
+   |        +
+
+error: aborting due to 4 previous errors
+
diff --git a/tests/ui/suggestions/type-ascription-and-other-error.stderr b/tests/ui/suggestions/type-ascription-and-other-error.stderr
index 4efddca4b47..7f8b8b7470e 100644
--- a/tests/ui/suggestions/type-ascription-and-other-error.stderr
+++ b/tests/ui/suggestions/type-ascription-and-other-error.stderr
@@ -3,6 +3,11 @@ error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found
    |
 LL |     not rust;
    |         ^^^^ expected one of 8 possible tokens
+   |
+help: you might have meant to write a field access
+   |
+LL |     not.rust;
+   |        +
 
 error: aborting due to 1 previous error