fix(formatter): treat static block with only empty statements as empty (#27945)

Fixed panic on `{ ; }`.

`EmptyStatement` is removed, then `group` for `StaticBlock` failed to get its content.

crates/oxc_formatter/src/print/class.rs

@@ -18,6 +18,7 @@ use crate::{
     },
     parentheses::NeedsParentheses,
     print::{
+        block_statement::is_empty_block,
         function::{
             function_content_end, function_signature_end, should_group_function_parameters,
         },
@@ -174,7 +175,7 @@ impl<'a> FormatWrite<'a> for AstNode<'a, StaticBlock<'a>> {
     fn write(&self, f: &mut JsFormatter<'_, 'a>) {
         write!(f, ["static", space(), "{"]);
 
-        if self.body.is_empty() {
+        if is_empty_block(&self.body) {
             write!(f, [format_dangling_comments(self.span).with_block_indent()]);
         } else {
             write!(f, [block_indent(&self.body())]);

crates/oxc_formatter/tests/fixtures/js/class/static-block-empty-statements.js

@@ -0,0 +1,15 @@
+class A {
+  static {
+    ;
+  }
+}
+class B {
+  static {
+    ;
+    // comment
+    ;
+  }
+}
+class C {
+  static {}
+}

crates/oxc_formatter/tests/fixtures/js/class/static-block-empty-statements.js.snap

@@ -0,0 +1,52 @@
+---
+source: crates/oxc_formatter/tests/fixtures/mod.rs
+---
+==================== Input ====================
+class A {
+  static {
+    ;
+  }
+}
+class B {
+  static {
+    ;
+    // comment
+    ;
+  }
+}
+class C {
+  static {}
+}
+
+==================== Output ====================
+------------------
+{ printWidth: 80 }
+------------------
+class A {
+  static {}
+}
+class B {
+  static {
+    // comment
+  }
+}
+class C {
+  static {}
+}
+
+-------------------
+{ printWidth: 100 }
+-------------------
+class A {
+  static {}
+}
+class B {
+  static {
+    // comment
+  }
+}
+class C {
+  static {}
+}
+
+===================== End =====================