Keep all bytes of one UTF-8 char on same line (no split)

[skorobkov]

mimemail:rfc2047_utf8_encode/1 can splite multibyte UTF-8 character to difrent lines.
Example:
Russian word "Информация", mimemail:rfc2047_utf8_encode/1 converting it into 2 strings
=?UTF-8?Q?=D0=98=D0=BD=D1=84=D0=BE=D1=80=D0=BC=D0=B0=D1=86=D0=B8=D1?=
=?UTF-8?Q?=8F?=
Last character "и" (=D1=8F) splitted, and dont show correctly in mail-readers.

[seriyps]

AFAIK, rfc2047_utf8_encode should produce strings not longer than 76 chars. If your version detects such a split does it move it to next line or broke 76 char limit?

Please, also add unittests!

[skorobkov]

Is "\r\n" counted in this 76 bytes?

[skorobkov]

mimemail:rfc2047_utf8_encode(unicode:characters_to_binary("€ € € € € 1234 € € € € 123 € € € € € 1234€"))]) produce this strings:

=?UTF-8?Q?=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20123?=
 =?UTF-9?Q?4=20=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20123=20?=
 =?UTF-9?Q?=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20=E2=82=AC=20123?=
 =?UTF-9?Q?4=E2=82=AC?=

Each encoded line not longer 75 bytes (76 with first space character).

[mworrell]

@seriyps Do you think the line length issue is resolved?

[seriyps]

@mworrell I guess it is, but still no unittests for this functionality

[mworrell]

@skorobkov can you add your example (with all the €) as an unit test?

[skorobkov]

Sorry for delay.
I have added unit test.

[seriyps]

According to http://erlang.org/doc/apps/eunit/chapter.html#Assert_macros it's recommended to place 'expected' as a first argument and 'actual result' as 2nd of assertEqual

[seriyps]

Looks good

[mworrell]

I also like it. Merging.

@skorobkov Thank you!