…rom test code

…sformFromAsyncIterable` class

…d to a simple `createSource()` function

+ Re-create the `Transform` object every time testing.
+ Simplify tests that differ only in options with `describe.each()`.

…the `try ... catch` statement

…call the callback passed to `_flush()` method after finish

…ng a stream

…g a stream

…terable` class

+ Rename the `done` property to `transformCallback
+ Rename the `callDoneFn` method to `callTransformCallback`
+ Remove the `pushError` method and add `finish` method in its place

+ Added a test that returns multiple chunks
+ Added a test for the type of chunks contained in the source

If there is a possibility that either the `objectMode` or the `readableObjectMode` option is not `true`, the return value should not be `unknown`.

… the next chunk is needed, not after transforming a chunk

Index signatures and `boolean` types are now supported.

…g in the stream

…ning

Promise objects should only be created in tests.
Creating it during test case generation could cause Promise errors to affect unrelated code.

…the stream

We have not found a way to control when data is read from the Readable stream.

…TransformFromAsyncIterable#finish()` method

Code Climate reported:

+ Function `finish` has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring.

…rmFromAsyncIterable` class

…`TransformFromAsyncIterable` class

This reverts commit 28e9901.

… chunks

see nodejs/node#34274

…s after processing all chunks has been fixed in Node v15

…etting all the chunks

This bug has been fixed in Node.js v15.

+ https://github.com/nodejs/node/blob/master/doc/changelogs/CHANGELOG_V15.md#15.0.0
+ nodejs/node#34314

However, we have found a workaround that works for anything less than Node.js v15, so we will attempt to fix this bug in this package.

…tting all the chunks

…t code readable and organized

…eScript

The size of the package is now smaller if `src` directory contents are included.

…ored

…disallowed in options

…op of file