fix(formatter): improve handling of dangling comments in if statements

Author: Dunqing

crates/oxc_formatter/src/write/mod.rs

@@ -836,14 +836,17 @@ impl<'a> FormatWrite<'a> for AstNode<'a, IfStatement<'a>> {
             }
 
             if has_dangling_comments {
-                write!(
-                    f,
-                    FormatDanglingComments::Comments { comments, indent: DanglingIndentMode::None }
-                )?;
-
                 if has_line_comment {
+                    write!(f, FormatTrailingComments::Comments(comments))?;
                     write!(f, hard_line_break())?;
                 } else {
+                    write!(
+                        f,
+                        FormatDanglingComments::Comments {
+                            comments,
+                            indent: DanglingIndentMode::None
+                        }
+                    )?;
                     write!(f, space())?;
                 }
             }

crates/oxc_formatter/tests/fixtures/ts/comments/if.ts

@@ -0,0 +1,8 @@
+if (true) {}
+
+// comment1
+else if (false) {}
+
+// comment2
+
+else {}

crates/oxc_formatter/tests/fixtures/ts/comments/if.ts.snap

@@ -0,0 +1,25 @@
+---
+source: crates/oxc_formatter/tests/fixtures/mod.rs
+---
+==================== Input ====================
+if (true) {}
+
+// comment1
+else if (false) {}
+
+// comment2
+
+else {}
+==================== Output ====================
+if (true) {
+}
+
+// comment1
+else if (false) {
+}
+
+// comment2
+else {
+}
+
+===================== End =====================