do not reverse the expected type and found type for ObligationCauseCode of IfExpressionWithNoElse

this will fix #102397

compiler/rustc_hir_analysis/src/check/_match.rs

@@ -259,7 +259,7 @@ pub(super) fn if_fallback_coercion<T>(
                 err.help("consider adding an `else` block that evaluates to the expected type");
                 error = true;
             },
-            ret_reason.is_none(),
+            false,
         );
         error
     }

src/test/ui/async-await/issue-66387-if-without-else.stderr

@@ -4,7 +4,7 @@ error[E0317]: `if` may be missing an `else` clause
 LL | /     if true {
 LL | |         return 0;
 LL | |     }
-   | |_____^ expected `()`, found `i32`
+   | |_____^ expected `i32`, found `()`
    |
    = note: `if` expressions without `else` evaluate to `()`
    = help: consider adding an `else` block that evaluates to the expected type

src/test/ui/consts/control-flow/issue-50577.stderr

@@ -2,7 +2,7 @@ error[E0317]: `if` may be missing an `else` clause
   --> $DIR/issue-50577.rs:3:16
    |
 LL |         Drop = assert_eq!(1, 1),
-   |                ^^^^^^^^^^^^^^^^ expected `()`, found `isize`
+   |                ^^^^^^^^^^^^^^^^ expected `isize`, found `()`
    |
    = note: `if` expressions without `else` evaluate to `()`
    = help: consider adding an `else` block that evaluates to the expected type

src/test/ui/expr/if/if-without-else-result.rs

@@ -1,6 +1,6 @@
 fn main() {
     let a = if true { true };
     //~^ ERROR `if` may be missing an `else` clause [E0317]
-    //~| expected `()`, found `bool`
+    //~| expected `bool`, found `()`
     println!("{}", a);
 }

src/test/ui/expr/if/if-without-else-result.stderr

@@ -5,7 +5,7 @@ LL |     let a = if true { true };
    |             ^^^^^^^^^^----^^
    |             |         |
    |             |         found here
-   |             expected `()`, found `bool`
+   |             expected `bool`, found `()`
    |
    = note: `if` expressions without `else` evaluate to `()`
    = help: consider adding an `else` block that evaluates to the expected type

src/test/ui/expr/if/issue-4201.rs

@@ -3,7 +3,7 @@ fn main() {
         0
     } else if false {
 //~^ ERROR `if` may be missing an `else` clause
-//~| expected `()`, found integer
+//~| expected integer, found `()`
         1
     };
 }

src/test/ui/expr/if/issue-4201.stderr

@@ -8,7 +8,7 @@ LL | |
 LL | |         1
    | |         - found here
 LL | |     };
-   | |_____^ expected `()`, found integer
+   | |_____^ expected integer, found `()`
    |
    = note: `if` expressions without `else` evaluate to `()`
    = help: consider adding an `else` block that evaluates to the expected type

src/test/ui/issues/issue-19991.rs

@@ -3,7 +3,7 @@
 
 fn main() {
     if let Some(homura) = Some("madoka") { //~  ERROR missing an `else` clause
-                                           //~| expected `()`, found integer
+                                           //~| expected integer, found `()`
         765
     };
 }

src/test/ui/issues/issue-19991.stderr

@@ -6,7 +6,7 @@ LL | |
 LL | |         765
    | |         --- found here
 LL | |     };
-   | |_____^ expected `()`, found integer
+   | |_____^ expected integer, found `()`
    |
    = note: `if` expressions without `else` evaluate to `()`
    = help: consider adding an `else` block that evaluates to the expected type