Merge pull request #2274 from topecongiro/better-error-msg

Attempt to improve error meassage from rustfmt

Author: nrc

src/bin/rustfmt.rs

@@ -350,7 +350,7 @@ fn main() {
             }
         }
         Err(e) => {
-            print_usage_to_stderr(&opts, &e.to_string());
+            eprintln!("{}", e.to_string());
             1
         }
     };
@@ -364,23 +364,18 @@ fn main() {
     std::process::exit(exit_code);
 }
 
-macro_rules! print_usage {
-    ($print:ident, $opts:ident, $reason:expr) => ({
-        let msg = format!(
-            "{}\n\nusage: {} [options] <file>...",
-            $reason,
-            env::args_os().next().unwrap().to_string_lossy()
-        );
-        $print!("{}", $opts.usage(&msg));
-    })
-}
-
 fn print_usage_to_stdout(opts: &Options, reason: &str) {
-    print_usage!(println, opts, reason);
-}
-
-fn print_usage_to_stderr(opts: &Options, reason: &str) {
-    print_usage!(eprintln, opts, reason);
+    let sep = if reason.is_empty() {
+        String::new()
+    } else {
+        format!("{}\n\n", reason)
+    };
+    let msg = format!(
+        "{}Format Rust code\n\nusage: {} [options] <file>...",
+        sep,
+        env::args_os().next().unwrap().to_string_lossy()
+    );
+    println!("{}", opts.usage(&msg));
 }
 
 fn print_version() {

src/config.rs

@@ -394,22 +394,23 @@ macro_rules! create_config {
                             $(
                                 stringify!($i) => (),
                             )+
-                                _ => {
-                                    let msg =
-                                        &format!("Warning: Unknown configuration option `{}`\n",
-                                                 key);
-                                    err.push_str(msg)
-                                }
+                            _ => {
+                                let msg =
+                                    &format!("Warning: Unknown configuration option `{}`\n", key);
+                                err.push_str(msg)
+                            }
                         }
                     }
                 }
                 match parsed.try_into() {
-                    Ok(parsed_config) =>
-                        Ok(Config::default().fill_from_parsed_config(parsed_config)),
+                    Ok(parsed_config) => {
+                        eprintln!("{}", err);
+                        Ok(Config::default().fill_from_parsed_config(parsed_config))
+                    }
                     Err(e) => {
                         err.push_str("Error: Decoding config file failed:\n");
                         err.push_str(format!("{}\n", e).as_str());
-                        err.push_str("Please check your config file.\n");
+                        err.push_str("Please check your config file.");
                         Err(err)
                     }
                 }