Suggest expressions' fields even if they're not ADTs

Author: compiler-errors

compiler/rustc_typeck/src/check/expr.rs

@@ -2611,15 +2611,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // up to a depth of three
             None
         } else {
-            // recursively search fields of `candidate_field` if it's a ty::Adt
             field_path.push(candidate_field.ident(self.tcx).normalize_to_macros_2_0());
             let field_ty = candidate_field.ty(self.tcx, subst);
-            if let Some((nested_fields, subst)) = self.get_field_candidates(span, field_ty) {
-                for field in nested_fields.iter() {
+            if matches(candidate_field, field_ty) {
+                return Some(field_path);
+            } else if let Some((nested_fields, subst)) = self.get_field_candidates(span, field_ty) {
+                // recursively search fields of `candidate_field` if it's a ty::Adt
+                for field in nested_fields {
                     if field.vis.is_accessible_from(id, self.tcx) {
-                        if matches(candidate_field, field_ty) {
-                            return Some(field_path);
-                        } else if let Some(field_path) = self.check_for_nested_field_satisfying(
+                        if let Some(field_path) = self.check_for_nested_field_satisfying(
                             span,
                             matches,
                             field,

src/test/ui/copy-a-resource.stderr

@@ -10,6 +10,10 @@ LL |     let _y = x.clone();
    = help: items from traits can only be used if the trait is implemented and in scope
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let _y = x.i.clone();
+   |                ++
 
 error: aborting due to previous error
 

src/test/ui/issues/issue-2823.stderr

@@ -10,6 +10,10 @@ LL |     let _d = c.clone();
    = help: items from traits can only be used if the trait is implemented and in scope
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let _d = c.x.clone();
+   |                ++
 
 error: aborting due to previous error
 

src/test/ui/issues/issue-31173.stderr

@@ -33,6 +33,10 @@ LL | pub struct TakeWhile<I, P> {
            which is required by `Cloned<TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 6:43]>>: Iterator`
            `Cloned<TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 6:43]>>: Iterator`
            which is required by `&mut Cloned<TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 6:43]>>: Iterator`
+help: one of the expressions' fields has a method of the same name
+   |
+LL |         .it.collect();
+   |          +++
 
 error: aborting due to 2 previous errors
 

src/test/ui/issues/issue-39175.stderr

@@ -5,6 +5,10 @@ LL |     Command::new("echo").arg("hello").exec();
    |                                       ^^^^ method not found in `&mut Command`
    |
    = help: items from traits can only be used if the trait is in scope
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     Command::new("echo").arg("hello").inner.exec();
+   |                                       ++++++
 help: the following trait is implemented but not in scope; perhaps add a `use` for it:
    |
 LL | use std::os::unix::process::CommandExt;

src/test/ui/mismatched_types/issue-36053-2.stderr

@@ -35,6 +35,10 @@ LL | pub struct Filter<I, P> {
            which is required by `Filter<Fuse<std::iter::Once<&str>>, [closure@$DIR/issue-36053-2.rs:7:39: 7:48]>: Iterator`
            `Filter<Fuse<std::iter::Once<&str>>, [closure@$DIR/issue-36053-2.rs:7:39: 7:48]>: Iterator`
            which is required by `&mut Filter<Fuse<std::iter::Once<&str>>, [closure@$DIR/issue-36053-2.rs:7:39: 7:48]>: Iterator`
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     once::<&str>("str").fuse().filter(|a: &str| true).iter.count();
+   |                                                       +++++
 
 error: aborting due to 2 previous errors
 

src/test/ui/noncopyable-class.stderr

@@ -10,6 +10,14 @@ LL |     let _y = x.clone();
    = help: items from traits can only be used if the trait is implemented and in scope
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let _y = x.i.clone();
+   |                ++
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let _y = x.j.x.clone();
+   |                ++++
 
 error: aborting due to previous error
 

src/test/ui/suggestions/import-trait-for-method-call.stderr

@@ -10,6 +10,10 @@ LL |     fn finish(&self) -> u64;
    |        ------ the method is available for `DefaultHasher` here
    |
    = help: items from traits can only be used if the trait is in scope
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     h.0.finish()
+   |       ++
 help: the following trait is implemented but not in scope; perhaps add a `use` for it:
    |
 LL | use std::hash::Hasher;

src/test/ui/suggestions/mut-borrow-needed-by-trait.stderr

@@ -41,6 +41,16 @@ LL | pub struct BufWriter<W: Write> {
            `&dyn std::io::Write: std::io::Write`
            which is required by `BufWriter<&dyn std::io::Write>: std::io::Write`
    = note: this error originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: one of the expressions' fields has a method of the same name
+  --> $SRC_DIR/core/src/macros/mod.rs:LL:COL
+   |
+LL |         $dst.inner.write_fmt($crate::format_args_nl!($($arg)*))
+   |              ++++++
+help: one of the expressions' fields has a method of the same name
+  --> $SRC_DIR/core/src/macros/mod.rs:LL:COL
+   |
+LL |         $dst.buf.write_fmt($crate::format_args_nl!($($arg)*))
+   |              ++++
 
 error: aborting due to 3 previous errors
 

src/test/ui/suggestions/suggest-using-chars.stderr

@@ -25,6 +25,10 @@ help: because of the in-memory representation of `&str`, to obtain an `Iterator`
    |
 LL |     let _ = String::from("bar").chars();
    |                                 ~~~~~
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let _ = String::from("bar").vec.iter();
+   |                                 ++++
 
 error[E0599]: no method named `iter` found for reference `&String` in the current scope
   --> $DIR/suggest-using-chars.rs:5:36
@@ -36,6 +40,10 @@ help: because of the in-memory representation of `&str`, to obtain an `Iterator`
    |
 LL |     let _ = (&String::from("bar")).chars();
    |                                    ~~~~~
+help: one of the expressions' fields has a method of the same name
+   |
+LL |     let _ = (&String::from("bar")).vec.iter();
+   |                                    ++++
 
 error[E0599]: no method named `iter` found for type `{integer}` in the current scope
   --> $DIR/suggest-using-chars.rs:6:15