---
source: crates/biome_js_analyze/tests/spec_tests.rs
expression: invalid.js
---
# Input
```jsx
export function f(a = 0, b) {}

export function g(a, b = 0, c) {}

export function g(a, b /* before */ = /* mid */ 0/* after */) {}

export function g(a, b /* before */ = /* mid */ 0 /* after */ /* after comma */, c) {}

export function u(a=5, b, c) {}

```

# Diagnostics
```
invalid.js:1:19 lint/style/useDefaultParameterLast  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This default parameter should follow the last required parameter or should be a required parameter.
  
  > 1 │ export function f(a = 0, b) {}
      │                   ^^^^^
    2 │ 
    3 │ export function g(a, b = 0, c) {}
  
  i The last required parameter is here:
  
  > 1 │ export function f(a = 0, b) {}
      │                          ^
    2 │ 
    3 │ export function g(a, b = 0, c) {}
  
  i A default parameter that precedes a required parameter cannot be omitted at call site.
  
  i Unsafe fix: Turn the parameter into a required parameter.
  
    1 │ export·function·f(a·=·0,·b)·{}
      │                    ----       

```

```
invalid.js:3:22 lint/style/useDefaultParameterLast  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This default parameter should follow the last required parameter or should be a required parameter.
  
    1 │ export function f(a = 0, b) {}
    2 │ 
  > 3 │ export function g(a, b = 0, c) {}
      │                      ^^^^^
    4 │ 
    5 │ export function g(a, b /* before */ = /* mid */ 0/* after */) {}
  
  i The last required parameter is here:
  
    1 │ export function f(a = 0, b) {}
    2 │ 
  > 3 │ export function g(a, b = 0, c) {}
      │                             ^
    4 │ 
    5 │ export function g(a, b /* before */ = /* mid */ 0/* after */) {}
  
  i A default parameter that precedes a required parameter cannot be omitted at call site.
  
  i Unsafe fix: Turn the parameter into a required parameter.
  
    3 │ export·function·g(a,·b·=·0,·c)·{}
      │                       ----       

```

```
invalid.js:7:22 lint/style/useDefaultParameterLast  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This default parameter should follow the last required parameter or should be a required parameter.
  
    5 │ export function g(a, b /* before */ = /* mid */ 0/* after */) {}
    6 │ 
  > 7 │ export function g(a, b /* before */ = /* mid */ 0 /* after */ /* after comma */, c) {}
      │                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    8 │ 
    9 │ export function u(a=5, b, c) {}
  
  i The last required parameter is here:
  
    5 │ export function g(a, b /* before */ = /* mid */ 0/* after */) {}
    6 │ 
  > 7 │ export function g(a, b /* before */ = /* mid */ 0 /* after */ /* after comma */, c) {}
      │                                                                                  ^
    8 │ 
    9 │ export function u(a=5, b, c) {}
  
  i A default parameter that precedes a required parameter cannot be omitted at call site.
  
  i Unsafe fix: Turn the parameter into a required parameter.
  
    7 │ export·function·g(a,·b·/*·before·*/·=·/*·mid·*/·0·/*·after·*/·/*·after·comma·*/,·c)·{}
      │                                     --------------                                    

```

```
invalid.js:9:19 lint/style/useDefaultParameterLast  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This default parameter should follow the last required parameter or should be a required parameter.
  
     7 │ export function g(a, b /* before */ = /* mid */ 0 /* after */ /* after comma */, c) {}
     8 │ 
   > 9 │ export function u(a=5, b, c) {}
       │                   ^^^
    10 │ 
  
  i The last required parameter is here:
  
     7 │ export function g(a, b /* before */ = /* mid */ 0 /* after */ /* after comma */, c) {}
     8 │ 
   > 9 │ export function u(a=5, b, c) {}
       │                           ^
    10 │ 
  
  i A default parameter that precedes a required parameter cannot be omitted at call site.
  
  i Unsafe fix: Turn the parameter into a required parameter.
  
    9 │ export·function·u(a=5,·b,·c)·{}
      │                    --          

```