Up until now, the default encoding for this is `binary`, but
this is scheduled to change in Node 8. Since this module is
currently always passing string input to the `Hash` object,
it needs to account for that.

A better fix would likely involve dropping all strings handling
and treating binary data using Buffer objects, but I kept
this change minimal to avoid any breakage.

Refs: nodejs/node#8611

Up until now, the default encoding for this is `binary`, but
this is scheduled to change in Node 8. Since this module is
currently always passing string input to the `Hash` object,
it needs to account for that.

A better fix would likely involve dropping all strings handling
and treating binary data using Buffer objects, but I kept
this change minimal to avoid any breakage.

Refs: nodejs/node#8611

PullRequest #5522 and #5500 described the change
of the default encoding into UTF8 in crypto functions.

This however was only changed for the non-streaming API.
The streaming API still used binary as the default encoding.

This commit will change the default streaming API encoding to UTF8
to make both APIs behave the same.

It will also add tests to validate the behavior.

Refs: #5522
Refs: #5500
PR-URL: #8611
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

PullRequest nodejs#5522 and nodejs#5500 described the change
of the default encoding into UTF8 in crypto functions.

This however was only changed for the non-streaming API.
The streaming API still used binary as the default encoding.

This commit will change the default streaming API encoding to UTF8
to make both APIs behave the same.

It will also add tests to validate the behavior.

Refs: nodejs#5522
Refs: nodejs#5500
PR-URL: nodejs#8611
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

This only affects the writable side of LazyTransform and should not
change the behavior of any LazyTransform streams (Cipher, Decipher,
Cipheriv, Decipheriv, Hash, Hmac).

If the user does not set defaultEncoding when creating a transform
stream, WritableState uses 'utf8' by default. Only LazyTransform
overwrites this with the return value of getDefaultEncoding(). This
was necessary when crypto.DEFAULT_ENCODING still existed. Now that
DEFAULT_ENCODING has been removed, getDefaultEncoding() always returns
'buffer'. The writable side of LazyTransform appears to treat 'utf8'
and 'buffer' in exactly the same way. Therefore, there seems to be no
need to overwrite _writableState.defaultEncoding at this point.

Nevertheless, because Node.js has failed to hide implementation details
such as _writableState from the ecosystem, we may want to consider this
a breaking change.

Refs: nodejs#47182
Refs: nodejs#8611

This only affects the writable side of LazyTransform and should not
change the behavior of any LazyTransform streams (Cipher, Decipher,
Cipheriv, Decipheriv, Hash, Hmac).

If the user does not set defaultEncoding when creating a transform
stream, WritableState uses 'utf8' by default. Only LazyTransform
overwrites this with 'buffer' for strict backward compatibility. This
was necessary when crypto.DEFAULT_ENCODING still existed. Now that
DEFAULT_ENCODING has been removed, defaultEncoding is always 'buffer'.
The writable side of LazyTransform appears to treat 'utf8' and 'buffer'
in exactly the same way. Therefore, there seems to be no need to
overwrite _writableState.defaultEncoding at this point.

Nevertheless, because Node.js has failed to hide implementation details
such as _writableState from the ecosystem, we may want to consider this
a breaking change.

Refs: nodejs#47182
Refs: nodejs#8611

This only affects the writable side of LazyTransform and should not
change the behavior of any LazyTransform streams (Cipher, Decipher,
Cipheriv, Decipheriv, Hash, Hmac).

If the user does not set defaultEncoding when creating a transform
stream, WritableState uses 'utf8' by default. Only LazyTransform
overwrites this with 'buffer' for strict backward compatibility. This
was necessary when crypto.DEFAULT_ENCODING still existed. Now that
DEFAULT_ENCODING has been removed, defaultEncoding is always 'buffer'.
The writable side of LazyTransform appears to treat 'utf8' and 'buffer'
in exactly the same way. Therefore, there seems to be no need to
overwrite _writableState.defaultEncoding at this point.

Nevertheless, because Node.js has failed to hide implementation details
such as _writableState from the ecosystem, we may want to consider this
a breaking change.

Refs: #47182
Refs: #8611
PR-URL: #49140
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

This only affects the writable side of LazyTransform and should not
change the behavior of any LazyTransform streams (Cipher, Decipher,
Cipheriv, Decipheriv, Hash, Hmac).

If the user does not set defaultEncoding when creating a transform
stream, WritableState uses 'utf8' by default. Only LazyTransform
overwrites this with 'buffer' for strict backward compatibility. This
was necessary when crypto.DEFAULT_ENCODING still existed. Now that
DEFAULT_ENCODING has been removed, defaultEncoding is always 'buffer'.
The writable side of LazyTransform appears to treat 'utf8' and 'buffer'
in exactly the same way. Therefore, there seems to be no need to
overwrite _writableState.defaultEncoding at this point.

Nevertheless, because Node.js has failed to hide implementation details
such as _writableState from the ecosystem, we may want to consider this
a breaking change.

Refs: nodejs#47182
Refs: nodejs#8611
PR-URL: nodejs#49140
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>