fix(rome_formatter): measure first variant of BestFitting in flat mode

crates/rome_formatter/src/macros.rs

@@ -146,9 +146,7 @@ macro_rules! format {
 ///
 /// ## Examples
 ///
-///  Temporarily ignored because [BestFitting] needs to be adjusted due to the
-/// `fits_element_on_line` changes in https://github.com/rome/tools/pull/2645
-/// ```ignore
+/// ```
 /// use rome_formatter::{Formatted, LineWidth, format, format_args};
 /// use rome_formatter::prelude::*;
 ///

crates/rome_formatter/src/printer/mod.rs

@@ -272,17 +272,20 @@ impl<'a> Printer<'a> {
                                 // Test if this variant fits and if so, use it. Otherwise try the next
                                 // variant.
 
-                                if fits_on_line(
-                                    &[variant],
-                                    args.with_print_mode(PrintMode::Expanded),
-                                    queue,
-                                    self,
-                                ) {
+                                // Try to fit only the first variant on a single line
+                                let mode = if index == 0 {
+                                    PrintMode::Flat
+                                } else {
+                                    PrintMode::Expanded
+                                };
+
+                                if fits_on_line(&[variant], args.with_print_mode(mode), queue, self)
+                                {
                                     self.state.measured_group_fits = true;
 
                                     queue.enqueue(PrintElementCall::new(
                                         variant,
-                                        args.with_print_mode(PrintMode::Expanded),
+                                        args.with_print_mode(mode),
                                     ));
                                     return;
                                 }