Reorder type mismatch suggestions

Suggestions are reordered to to make sure potential missing expect on Option/Result runs
before the suggestion to remove the last method call

Author: 3tilley

compiler/rustc_hir_typeck/src/demand.rs

@@ -43,6 +43,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Use `||` to give these suggestions a precedence
         let suggested = self.suggest_missing_parentheses(err, expr)
+            || self.suggest_missing_unwrap_expect(err, expr, expected, expr_ty)
             || self.suggest_remove_last_method_call(err, expr, expected)
             || self.suggest_associated_const(err, expr, expected)
             || self.suggest_deref_ref_or_into(err, expr, expected, expr_ty, expected_ty_expr)
@@ -58,8 +59,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             || self.suggest_into(err, expr, expr_ty, expected)
             || self.suggest_floating_point_literal(err, expr, expected)
             || self.suggest_null_ptr_for_literal_zero_given_to_ptr_arg(err, expr, expected)
-            || self.suggest_coercing_result_via_try_operator(err, expr, expected, expr_ty)
-            || self.suggest_missing_unwrap_expect(err, expr, expected, expr_ty);
+            || self.suggest_coercing_result_via_try_operator(err, expr, expected, expr_ty);
 
         if !suggested {
             self.note_source_of_type_mismatch_constraint(

tests/ui/suggestions/issue-117669.rs

@@ -0,0 +1,3 @@
+fn main() {
+    let abs: i32 = 3i32.checked_abs();
+}

tests/ui/suggestions/issue-117669.stderr

@@ -0,0 +1,16 @@
+error[E0308]: mismatched types
+ --> $DIR/issue-177699.rs:2:20
+  |
+2 |     let abs: i32 = 3i32.checked_abs();
+  |              ---   ^^^^^^^^^^^^^^^^^^ expected `i32`, found `Option<i32>`
+  |              |
+  |              expected due to this
+  |
+  = note: expected type `i32`
+             found enum `Option<i32>`
+help: consider using `Option::expect` to unwrap the `Option<i32>` value, panicking if the value is an `Option::None`
+  |
+2 |     let abs: i32 = 3i32.checked_abs().expect("REASON");
+  |                                      +++++++++++++++++
+
+For more information about this error, try `rustc --explain E0308`.