Match Black's formatting of trailing comments containing NBSP (#7030)

crates/ruff_python_formatter/src/comments/format.rs

@@ -474,18 +474,19 @@ fn normalize_comment<'a>(
     if content.starts_with('\u{A0}') {
         let trimmed = content.trim_start_matches('\u{A0}');
 
-        // Black adds a space before the non-breaking space if part of a type pragma.
         if trimmed.trim_start().starts_with("type:") {
-            return Ok(Cow::Owned(std::format!("# \u{A0}{trimmed}")));
-        }
-
-        // Black replaces the non-breaking space with a space if followed by a space.
-        if trimmed.starts_with(' ') {
-            return Ok(Cow::Owned(std::format!("# {trimmed}")));
+            // Black adds a space before the non-breaking space if part of a type pragma.
+            Ok(Cow::Owned(std::format!("# {content}")))
+        } else if trimmed.starts_with(' ') {
+            // Black replaces the non-breaking space with a space if followed by a space.
+            Ok(Cow::Owned(std::format!("# {trimmed}")))
+        } else {
+            // Otherwise we replace the first non-breaking space with a regular space.
+            Ok(Cow::Owned(std::format!("# {}", &content["\u{A0}".len()..])))
         }
+    } else {
+        Ok(Cow::Owned(std::format!("# {}", content.trim_start())))
     }
-
-    Ok(Cow::Owned(std::format!("# {}", content.trim_start())))
 }
 
 /// A helper for stripping '#' from comments.

crates/ruff_python_formatter/tests/snapshots/format@trailing_comments.py.snap

@@ -65,11 +65,11 @@ i = ""  #          type: Add space before leading NBSP followed by spaces
 i = ""  # type: A space is added
 i = ""  #   type: Add space before leading NBSP followed by a space
 i = ""  #  type: Add space before leading NBSP
-i = ""  #  type: Add space before two leading NBSP
+i = ""  #   type: Add space before two leading NBSP
 
 
 # A noqa as `#\u{A0}\u{A0}noqa` becomes `# \u{A0}noqa`
-i = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"  # noqa
+i = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"  #  noqa
 ```