add ui tests for &raw not followed by const or mut

Author: rmehri01

tests/ui/raw-ref-op/missing-modifier/let-stmt.rs

@@ -0,0 +1,12 @@
+//! Check that `&raw` that isn't followed by `const` or `mut` produces a
+//! helpful error message.
+//!
+//! Related issue: <https://github.com/rust-lang/rust/issues/133231>.
+
+fn main() {
+    let foo = 2;
+    let _ = &raw foo;
+    //~^ ERROR expected one of
+    //~| HELP you might have meant to use a raw reference
+    //~| HELP you might have meant to write a field access
+}

tests/ui/raw-ref-op/missing-modifier/let-stmt.stderr

@@ -0,0 +1,13 @@
+error: expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `foo`
+  --> $DIR/let-stmt.rs:8:18
+   |
+LL |     let _ = &raw foo;
+   |                  ^^^ expected one of 8 possible tokens
+   |
+help: you might have meant to write a field access
+   |
+LL |     let _ = &raw.foo;
+   |                 +
+
+error: aborting due to 1 previous error
+

tests/ui/raw-ref-op/missing-modifier/nested-array-expr.rs

@@ -0,0 +1,14 @@
+//! Check that `&raw` that isn't followed by `const` or `mut` produces a
+//! helpful error message.
+//!
+//! Related issue: <https://github.com/rust-lang/rust/issues/133231>.
+
+mod foo {
+    pub static A: i32 = 0;
+}
+
+fn main() {
+    [&raw foo::A; 3];
+    //~^ ERROR expected one of
+    //~| HELP you might have meant to use a raw reference
+}

tests/ui/raw-ref-op/missing-modifier/nested-array-expr.stderr

@@ -0,0 +1,8 @@
+error: expected one of `!`, `,`, `.`, `::`, `;`, `?`, `]`, `{`, or an operator, found `foo`
+  --> $DIR/nested-array-expr.rs:11:11
+   |
+LL |     [&raw foo::A; 3];
+   |           ^^^ expected one of 9 possible tokens
+
+error: aborting due to 1 previous error
+

tests/ui/raw-ref-op/missing-modifier/return-expr.rs

@@ -0,0 +1,16 @@
+//! Check that `&raw` that isn't followed by `const` or `mut` produces a
+//! helpful error message.
+//!
+//! Related issue: <https://github.com/rust-lang/rust/issues/133231>.
+
+mod foo {
+    pub static A: i32 = 0;
+}
+
+fn get_ref() -> *const i32 {
+    &raw foo::A
+    //~^ ERROR expected one of
+    //~| HELP you might have meant to use a raw reference
+}
+
+fn main() {}

tests/ui/raw-ref-op/missing-modifier/return-expr.stderr

@@ -0,0 +1,8 @@
+error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `foo`
+  --> $DIR/return-expr.rs:11:10
+   |
+LL |     &raw foo::A
+   |          ^^^ expected one of 8 possible tokens
+
+error: aborting due to 1 previous error
+