Suggest clone in user-write-code instead of inside macro

Signed-off-by: xizheyin <[email protected]>

Author: xizheyin

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -1302,8 +1302,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 None => ".clone()".to_string(),
             };
 
+            let span = expr.span.find_oldest_ancestor_in_same_ctxt().shrink_to_hi();
             diag.span_suggestion_verbose(
-                expr.span.shrink_to_hi(),
+                span,
                 "consider using clone here",
                 suggestion,
                 Applicability::MachineApplicable,

tests/ui/typeck/suggestions/suggest-clone-in-macro-issue-139253.rs

@@ -0,0 +1,21 @@
+// Make sure we don't suggest clone not in dbg macro
+
+#[derive(Clone, Debug)]
+struct Point<T> {
+    v: T,
+}
+
+#[derive(Clone, Debug)]
+struct S;
+
+fn foo(_: S) {}
+
+fn test1() {
+    let s = &S;
+    foo(dbg!(s)); //~ ERROR mismatched types
+}
+
+fn main() {
+    let a: Point<u8> = dbg!(Point { v: 42 });
+    let b: Point<u8> = dbg!(&a); //~ ERROR mismatched types [E0308]
+}

tests/ui/typeck/suggestions/suggest-clone-in-macro-issue-139253.stderr

@@ -0,0 +1,29 @@
+error[E0308]: mismatched types
+  --> $DIR/suggest-clone-in-macro-issue-139253.rs:15:9
+   |
+LL |     foo(dbg!(s));
+   |         ^^^^^^^ expected `S`, found `&S`
+   |
+   = note: this error originates in the macro `dbg` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: consider using clone here
+   |
+LL |     foo(dbg!(s).clone());
+   |                ++++++++
+
+error[E0308]: mismatched types
+  --> $DIR/suggest-clone-in-macro-issue-139253.rs:20:24
+   |
+LL |     let b: Point<u8> = dbg!(&a);
+   |                        ^^^^^^^^ expected `Point<u8>`, found `&Point<u8>`
+   |
+   = note: expected struct `Point<_>`
+           found reference `&Point<_>`
+   = note: this error originates in the macro `dbg` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: consider using clone here
+   |
+LL |     let b: Point<u8> = dbg!(&a).clone();
+   |                                ++++++++
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0308`.