2024-02-02 12:22:18 +03:00
|
|
|
export function assertNever(x: never): never {
|
|
|
|
bail('Unexpected object: ' + JSON.stringify(x))
|
|
|
|
}
|
|
|
|
|
|
|
|
export function assert(condition: boolean, message?: string): asserts condition {
|
|
|
|
if (!condition) bail(message ? `Assertion failed: ${message}` : 'Assertion failed')
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Checks if the given iterable has the specified length and throws an assertion error
|
|
|
|
* if the lengths do not match.
|
|
|
|
*
|
|
|
|
* @param iterable The iterable to check.
|
|
|
|
* @param length The expected length of the iterable.
|
|
|
|
* @param message Optional message for the assertion error.
|
|
|
|
* @return void
|
|
|
|
* @throws Error Will throw an error if the length does not match.
|
|
|
|
*
|
|
|
|
* The first five elements of the iterable will be displayed in the error message
|
|
|
|
* if the assertion fails. If the iterable contains more than five elements,
|
|
|
|
* the remaining elements will be represented as '...'.
|
|
|
|
*/
|
|
|
|
export function assertLength<T>(iterable: Iterable<T>, length: number, message?: string): void {
|
|
|
|
const convertedArray = Array.from(iterable)
|
|
|
|
const messagePrefix = message ? message + ' ' : ''
|
|
|
|
const elementRepresentation =
|
2024-03-06 18:34:07 +03:00
|
|
|
convertedArray.length > 5 ?
|
|
|
|
`${convertedArray.slice(0, 5).join(', ')},...`
|
|
|
|
: convertedArray.join(', ')
|
2024-02-02 12:22:18 +03:00
|
|
|
assert(
|
|
|
|
convertedArray.length === length,
|
|
|
|
`${messagePrefix}Expected iterable of length ${length}, got length ${convertedArray.length}. Elements: [${elementRepresentation}]`,
|
|
|
|
)
|
|
|
|
}
|
|
|
|
|
|
|
|
export function assertEmpty<T>(iterable: Iterable<T>, message?: string): void {
|
|
|
|
assertLength(iterable, 0, message)
|
|
|
|
}
|
|
|
|
|
|
|
|
export function assertEqual<T>(actual: T, expected: T, message?: string) {
|
|
|
|
const messagePrefix = message ? message + ' ' : ''
|
|
|
|
assert(actual === expected, `${messagePrefix}Expected ${expected}, got ${actual}.`)
|
|
|
|
}
|
|
|
|
|
|
|
|
export function assertNotEqual<T>(actual: T, unexpected: T, message?: string) {
|
|
|
|
const messagePrefix = message ? message + ' ' : ''
|
|
|
|
assert(actual !== unexpected, `${messagePrefix}Expected not ${unexpected}, got ${actual}.`)
|
|
|
|
}
|
|
|
|
|
|
|
|
export function assertDefined<T>(x: T | undefined, message?: string): asserts x is T {
|
|
|
|
const messagePrefix = message ? message + ' ' : ''
|
|
|
|
assert(x !== undefined, `${messagePrefix}Expected value to be defined.`)
|
|
|
|
}
|
|
|
|
|
|
|
|
export function assertUnreachable(): never {
|
|
|
|
bail('Unreachable code')
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Throw an error with provided message.
|
|
|
|
*
|
|
|
|
* It is convenient to use at the end of a nullable chain:
|
|
|
|
* ```ts
|
|
|
|
* const x = foo?.bar.baz?.() ?? bail('Expected foo.bar.baz to exist')
|
|
|
|
* ```
|
|
|
|
*/
|
|
|
|
export function bail(message: string): never {
|
|
|
|
throw new Error(message)
|
|
|
|
}
|