You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
19 lines
608 B
19 lines
608 B
import type { Equal, Expect } from '@type-challenges/utils'
|
|
|
|
type cases = [
|
|
Expect<Equal<SnakeCase<'hello'>, 'hello'>>,
|
|
Expect<Equal<SnakeCase<'userName'>, 'user_name'>>,
|
|
Expect<Equal<SnakeCase<'getElementById'>, 'get_element_by_id'>>,
|
|
Expect<Equal<SnakeCase<'getElementById' | 'getElementByClassNames'>, 'get_element_by_id' | 'get_element_by_class_names'>>,
|
|
]
|
|
|
|
type SnakeCase<
|
|
T extends string,
|
|
Acc extends string = '',
|
|
> =
|
|
T extends `${infer Head}${infer Tail}`
|
|
? Head extends Lowercase<Head>
|
|
? SnakeCase<Tail, `${Acc}${Head}`>
|
|
: SnakeCase<Tail, `${Acc}_${Lowercase<Head>}`>
|
|
: Acc
|
|
;
|