---
source: crates/biome_formatter_test/src/snapshot_builder.rs
info: js/class-extends/tuple-and-record.js
---

# Input

```js
class A extends {} {}
class B extends #{} {}

class C extends [] {}
class D extends #[] {}

```


# Prettier differences

```diff
--- Prettier
+++ Biome
@@ -1,5 +1,7 @@
 class A extends ({}) {}
-class B extends #{} {}
+class B extends #{}
+{
+}
 
 class C extends [] {}
 class D extends #[] {}
```

# Output

```js
class A extends ({}) {}
class B extends #{}
{
}

class C extends [] {}
class D extends #[] {}
```

# Errors
```
tuple-and-record.js:2:16 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × 'extends' list cannot be empty.
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                
    3 │ 
    4 │ class C extends [] {}
  
tuple-and-record.js:2:17 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × expected `{` but instead found `#`
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                 ^
    3 │ 
    4 │ class C extends [] {}
  
  i Remove #
  
tuple-and-record.js:2:18 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × Expected an identifier but instead found '{'.
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                  ^
    3 │ 
    4 │ class C extends [] {}
  
  i Expected an identifier here.
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                  ^
    3 │ 
    4 │ class C extends [] {}
  
tuple-and-record.js:2:17 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × expected a semicolon to end the class property, but found none
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                 ^
    3 │ 
    4 │ class C extends [] {}
  
tuple-and-record.js:2:18 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × Expected an identifier, a string literal, a number literal, a private field name, or a computed name but instead found '{'.
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                  ^
    3 │ 
    4 │ class C extends [] {}
  
  i Expected an identifier, a string literal, a number literal, a private field name, or a computed name here.
  
    1 │ class A extends {} {}
  > 2 │ class B extends #{} {}
      │                  ^
    3 │ 
    4 │ class C extends [] {}
  
tuple-and-record.js:5:16 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × 'extends' list cannot be empty.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                
    6 │ 
  
tuple-and-record.js:5:17 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × expected `{` but instead found `#`
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                 ^
    6 │ 
  
  i Remove #
  
tuple-and-record.js:5:18 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × Expected an identifier but instead found '['.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                  ^
    6 │ 
  
  i Expected an identifier here.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                  ^
    6 │ 
  
tuple-and-record.js:5:17 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × expected a semicolon to end the class property, but found none
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                 ^
    6 │ 
  
tuple-and-record.js:5:19 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × Expected an expression but instead found ']'.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                   ^
    6 │ 
  
  i Expected an expression here.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                   ^
    6 │ 
  
tuple-and-record.js:5:18 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × expected a semicolon to end the class property, but found none
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                  ^^
    6 │ 
  
tuple-and-record.js:5:21 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × Expected an identifier, a string literal, a number literal, a private field name, or a computed name but instead found '{'.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                     ^
    6 │ 
  
  i Expected an identifier, a string literal, a number literal, a private field name, or a computed name here.
  
    4 │ class C extends [] {}
  > 5 │ class D extends #[] {}
      │                     ^
    6 │ 
  

```