Rollup merge of #116296 - compiler-errors:default-return, r=estebank

More accurately point to where default return type should go

When getting the "default return type" span, instead of pointing to the low span of the next token, point to the high span of the previous token. This:

1. Makes forming return type suggestions more uniform, since we expect them all in the same place.
2. Arguably makes labels easier to understand, since we're pointing to where the implicit `-> ()` would've gone, rather than the starting brace or the semicolon.

r? ```@estebank```

7 files changed, 14 insertions, 17 deletions

diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_literal_unwrap.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_literal_unwrap.rs
index 937aac8d25e..24c0ea3f60a 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_literal_unwrap.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_literal_unwrap.rs
@@ -102,14 +102,10 @@ pub(super) fn check(
             ]),
             ("None", "unwrap_or_else", _) => match args[0].kind {
                 hir::ExprKind::Closure(hir::Closure {
-                    fn_decl:
-                        hir::FnDecl {
-                            output: hir::FnRetTy::DefaultReturn(span) | hir::FnRetTy::Return(hir::Ty { span, .. }),
-                            ..
-                        },
+                    body,
                     ..
                 }) => Some(vec![
-                    (expr.span.with_hi(span.hi()), String::new()),
+                    (expr.span.with_hi(cx.tcx.hir().body(*body).value.span.lo()), String::new()),
                     (expr.span.with_lo(args[0].span.hi()), String::new()),
                 ]),
                 _ => None,
diff --git a/src/tools/clippy/tests/ui-toml/too_many_arguments/too_many_arguments.stderr b/src/tools/clippy/tests/ui-toml/too_many_arguments/too_many_arguments.stderr
index a52e1fcb9e3..8b9d159b59c 100644
--- a/src/tools/clippy/tests/ui-toml/too_many_arguments/too_many_arguments.stderr
+++ b/src/tools/clippy/tests/ui-toml/too_many_arguments/too_many_arguments.stderr
@@ -2,7 +2,7 @@ error: this function has too many arguments (11/10)
   --> $DIR/too_many_arguments.rs:4:1
    |
 LL | fn too_many(p1: u8, p2: u8, p3: u8, p4: u8, p5: u8, p6: u8, p7: u8, p8: u8, p9: u8, p10: u8, p11: u8) {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `-D clippy::too-many-arguments` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::too_many_arguments)]`
diff --git a/src/tools/clippy/tests/ui/functions.stderr b/src/tools/clippy/tests/ui/functions.stderr
index 371ea161260..4b06cd03889 100644
--- a/src/tools/clippy/tests/ui/functions.stderr
+++ b/src/tools/clippy/tests/ui/functions.stderr
@@ -2,7 +2,7 @@ error: this function has too many arguments (8/7)
   --> $DIR/functions.rs:8:1
    |
 LL | fn bad(_one: u32, _two: u32, _three: &str, _four: bool, _five: f32, _six: f32, _seven: bool, _eight: ()) {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `-D clippy::too-many-arguments` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::too_many_arguments)]`
@@ -17,7 +17,7 @@ LL | |     two: u32,
 ...  |
 LL | |     eight: ()
 LL | | ) {
-   | |__^
+   | |_^
 
 error: this function has too many arguments (8/7)
   --> $DIR/functions.rs:48:5
@@ -29,7 +29,7 @@ error: this function has too many arguments (8/7)
   --> $DIR/functions.rs:58:5
    |
 LL |     fn bad_method(_one: u32, _two: u32, _three: &str, _four: bool, _five: f32, _six: f32, _seven: bool, _eight: ()) {}
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: this public function might dereference a raw pointer but is not marked `unsafe`
   --> $DIR/functions.rs:68:34
diff --git a/src/tools/clippy/tests/ui/must_use_unit.stderr b/src/tools/clippy/tests/ui/must_use_unit.stderr
index e67d9b5b9d8..f2ee185857d 100644
--- a/src/tools/clippy/tests/ui/must_use_unit.stderr
+++ b/src/tools/clippy/tests/ui/must_use_unit.stderr
@@ -4,7 +4,7 @@ error: this unit-returning function has a `#[must_use]` attribute
 LL | #[must_use]
    | ----------- help: remove the attribute
 LL | pub fn must_use_default() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `-D clippy::must-use-unit` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::must_use_unit)]`
@@ -23,7 +23,7 @@ error: this unit-returning function has a `#[must_use]` attribute
 LL | #[must_use = "With note"]
    | ------------------------- help: remove the attribute
 LL | pub fn must_use_with_note() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 3 previous errors
 
diff --git a/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.fixed b/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.fixed
index 87df1f8cb08..b17343aa9ba 100644
--- a/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.fixed
+++ b/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.fixed
@@ -23,7 +23,7 @@ fn unwrap_option_none() {
     let _val: u16 = 234;
     let _val: u16 = 234;
     let _val: u16 = { 234 };
-    let _val: u16 =  { 234 };
+    let _val: u16 = { 234 };
 
     panic!();
     panic!("this always happens");
@@ -31,7 +31,7 @@ fn unwrap_option_none() {
     234;
     234;
     { 234 };
-     { 234 };
+    { 234 };
 }
 
 fn unwrap_result_ok() {
diff --git a/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.stderr b/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.stderr
index 013907f59c4..4940091be60 100644
--- a/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.stderr
+++ b/src/tools/clippy/tests/ui/unnecessary_literal_unwrap.stderr
@@ -116,7 +116,7 @@ LL |     let _val: u16 = None.unwrap_or_else(|| -> u16 { 234 });
 help: remove the `None` and `unwrap_or_else()`
    |
 LL -     let _val: u16 = None.unwrap_or_else(|| -> u16 { 234 });
-LL +     let _val: u16 =  { 234 };
+LL +     let _val: u16 = { 234 };
    |
 
 error: used `unwrap()` on `None` value
@@ -187,7 +187,7 @@ LL |     None::<u16>.unwrap_or_else(|| -> u16 { 234 });
 help: remove the `None` and `unwrap_or_else()`
    |
 LL -     None::<u16>.unwrap_or_else(|| -> u16 { 234 });
-LL +      { 234 };
+LL +     { 234 };
    |
 
 error: used `unwrap()` on `Ok` value
diff --git a/src/tools/rustfmt/src/items.rs b/src/tools/rustfmt/src/items.rs
index d5bc38303e0..002cffa9b0c 100644
--- a/src/tools/rustfmt/src/items.rs
+++ b/src/tools/rustfmt/src/items.rs
@@ -2599,7 +2599,8 @@ fn rewrite_fn_base(
     if where_clause_str.is_empty() {
         if let ast::FnRetTy::Default(ret_span) = fd.output {
             match recover_missing_comment_in_span(
-                mk_sp(params_span.hi(), ret_span.hi()),
+                // from after the closing paren to right before block or semicolon
+                mk_sp(ret_span.lo(), span.hi()),
                 shape,
                 context,
                 last_line_width(&result),