silent formatting failure in match statements

[boemjay]

Error

rustfmt fails to format any branches inside a match statement if it cannot format the whole statement.

Expected Behaviour

All other branches in the match statement should be formatted correctly, even if one branch fails to format.

Steps to reproduce

Try to format the following main.rs:

fn main() {
    match true {
        false => {println!("nothing inside this match statement is formatted anymore")
        }
        _ => "String causing the failure xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx",
    };
}

Output of rustfmt --check:
None

Now remove one of the x placeholder characters in the string and format again.

Output of rustfmt --check:

 fn main() {
     match true {
-        false => {println!("nothing inside this match statement is formatted anymore")
+        false => {
+            println!("nothing inside this match statement is formatted anymore")
         }
-        _ => "String causing the failure xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx",
+        _ => {
+            "String causing the failure xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+        }
     };
 }

Additional Information

Tested on rustfmt 1.6.0-nightly (fcab248 2023-10-13)

[ytmimi]

Thanks for reaching out. This is a duplicate of #4797