fix the issue of shorthand in suggest_cloning

Author: chenyukang

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -452,7 +452,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     } = move_spans {
                         // We already suggest cloning for these cases in `explain_captures`.
                     } else {
-                        self.suggest_cloning(err, ty, move_span);
+                        self.suggest_cloning(err, ty, expr, move_span);
                     }
                 }
             }
@@ -727,9 +727,21 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         true
     }
 
-    fn suggest_cloning(&self, err: &mut Diagnostic, ty: Ty<'tcx>, span: Span) {
+    fn suggest_cloning(
+        &self,
+        err: &mut Diagnostic,
+        ty: Ty<'tcx>,
+        expr: &hir::Expr<'_>,
+        span: Span,
+    ) {
         let tcx = self.infcx.tcx;
         // Try to find predicates on *generic params* that would allow copying `ty`
+        let suggestion =
+            if let Some(symbol) = tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) {
+                format!(": {}.clone()", symbol)
+            } else {
+                ".clone()".to_owned()
+            };
         if let Some(clone_trait_def) = tcx.lang_items().clone_trait()
             && self.infcx
                 .type_implements_trait(
@@ -742,7 +754,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             err.span_suggestion_verbose(
                 span.shrink_to_hi(),
                 "consider cloning the value if the performance cost is acceptable",
-                ".clone()",
+                suggestion,
                 Applicability::MachineApplicable,
             );
         }

compiler/rustc_hir_typeck/src/demand.rs

@@ -15,7 +15,7 @@ use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, Article, AssocItem, Ty, TypeAndMut, TypeFoldable};
-use rustc_span::symbol::{sym, Symbol};
+use rustc_span::symbol::sym;
 use rustc_span::{BytePos, Span, DUMMY_SP};
 use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::ObligationCause;
@@ -997,7 +997,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 .collect();
 
             let suggestions_for = |variant: &_, ctor_kind, field_name| {
-                let prefix = match self.maybe_get_struct_pattern_shorthand_field(expr) {
+                let prefix = match self.tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) {
                     Some(ident) => format!("{ident}: "),
                     None => String::new(),
                 };
@@ -1240,39 +1240,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
-    pub(crate) fn maybe_get_struct_pattern_shorthand_field(
-        &self,
-        expr: &hir::Expr<'_>,
-    ) -> Option<Symbol> {
-        let hir = self.tcx.hir();
-        let local = match expr {
-            hir::Expr {
-                kind:
-                    hir::ExprKind::Path(hir::QPath::Resolved(
-                        None,
-                        hir::Path {
-                            res: hir::def::Res::Local(_),
-                            segments: [hir::PathSegment { ident, .. }],
-                            ..
-                        },
-                    )),
-                ..
-            } => Some(ident),
-            _ => None,
-        }?;
-
-        match hir.find_parent(expr.hir_id)? {
-            Node::ExprField(field) => {
-                if field.ident.name == local.name && field.is_shorthand {
-                    return Some(local.name);
-                }
-            }
-            _ => {}
-        }
-
-        None
-    }
-
     /// If the given `HirId` corresponds to a block with a trailing expression, return that expression
     pub(crate) fn maybe_get_block_expr(
         &self,
@@ -1467,7 +1434,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         ));
                     }
 
-                    let prefix = match self.maybe_get_struct_pattern_shorthand_field(expr) {
+                    let prefix = match self.tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) {
                         Some(ident) => format!("{ident}: "),
                         None => String::new(),
                     };
@@ -1661,7 +1628,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             )
                         };
 
-                        let prefix = match self.maybe_get_struct_pattern_shorthand_field(expr) {
+                        let prefix = match self.tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) {
                             Some(ident) => format!("{ident}: "),
                             None => String::new(),
                         };

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -395,7 +395,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         vec![(expr.span.shrink_to_hi(), format!(".{}()", conversion_method.name))]
                     };
                     let struct_pat_shorthand_field =
-                        self.maybe_get_struct_pattern_shorthand_field(expr);
+                        self.tcx.hir().maybe_get_struct_pattern_shorthand_field(expr);
                     if let Some(name) = struct_pat_shorthand_field {
                         sugg.insert(0, (expr.span.shrink_to_lo(), format!("{}: ", name)));
                     }
@@ -1069,7 +1069,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 )
                 .must_apply_modulo_regions()
           {
-            let suggestion = match self.maybe_get_struct_pattern_shorthand_field(expr) {
+            let suggestion = match self.tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) {
                 Some(ident) => format!(": {}.clone()", ident),
                 None => ".clone()".to_string()
             };
@@ -1247,7 +1247,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             return false;
         }
 
-        let suggestion = match self.maybe_get_struct_pattern_shorthand_field(expr) {
+        let suggestion = match self.tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) {
             Some(ident) => format!(": {}.is_some()", ident),
             None => ".is_some()".to_string(),
         };

compiler/rustc_middle/src/hir/map/mod.rs

@@ -1103,6 +1103,33 @@ impl<'hir> Map<'hir> {
             _ => None,
         }
     }
+
+    pub fn maybe_get_struct_pattern_shorthand_field(&self, expr: &Expr<'_>) -> Option<Symbol> {
+        let local = match expr {
+            Expr {
+                kind:
+                    ExprKind::Path(QPath::Resolved(
+                        None,
+                        Path {
+                            res: def::Res::Local(_), segments: [PathSegment { ident, .. }], ..
+                        },
+                    )),
+                ..
+            } => Some(ident),
+            _ => None,
+        }?;
+
+        match self.find_parent(expr.hir_id)? {
+            Node::ExprField(field) => {
+                if field.ident.name == local.name && field.is_shorthand {
+                    return Some(local.name);
+                }
+            }
+            _ => {}
+        }
+
+        None
+    }
 }
 
 impl<'hir> intravisit::Map<'hir> for Map<'hir> {

tests/ui/borrowck/copy-suggestion-region-vid.rs

@@ -1,3 +1,4 @@
+//@run-rustfix
 pub struct DataStruct();
 
 pub struct HelperStruct<'n> {

tests/ui/borrowck/copy-suggestion-region-vid.stderr

@@ -1,5 +1,5 @@
 error[E0382]: borrow of moved value: `helpers`
-  --> $DIR/copy-suggestion-region-vid.rs:12:43
+  --> $DIR/copy-suggestion-region-vid.rs:13:43
    |
 LL |         let helpers = [vec![], vec![]];
    |             ------- move occurs because `helpers` has type `[Vec<&i64>; 2]`, which does not implement the `Copy` trait
@@ -11,8 +11,8 @@ LL |         HelperStruct { helpers, is_empty: helpers[0].is_empty() }
    |
 help: consider cloning the value if the performance cost is acceptable
    |
-LL |         HelperStruct { helpers.clone(), is_empty: helpers[0].is_empty() }
-   |                               ++++++++
+LL |         HelperStruct { helpers: helpers.clone(), is_empty: helpers[0].is_empty() }
+   |                               +++++++++++++++++
 
 error: aborting due to previous error