Incorrect transcoding of text attachments

[dkop]

https://github.com/ddeboer/imap/blob/master/src/Message/Part.php#L182

            if ($this->getType() === self::TYPE_TEXT
                && strtolower($this->getCharset()) != 'utf-8'
            ) {
                $this->decodedContent = Transcoder::create()->transcode(
                    $this->decodedContent,
                    $this->getCharset()
                );
            }

This code use iconv() or mb_convert_encoding() for transcoding content of text file. $this->getCharset() detects encoding by parameters returned by imap_fetch_structure(). If there is no encoding parameter for attachment, then $this->getCharset() returns null, which is sent to mb_convert_encoding() as input encoding. But mb_convert_encoding() not in all cases can detect encoding of file. And in this case i have attachment file with broken and unrecoverable encoding.
May be there needed an optional parameter for method Part::getDecodedContent(). For example:

    public function getDecodedContent($keepUnseen = false, $convertToUtf8 = true) {
    ...
        if ($convertToUtf8 
            && $this->getType() === self::TYPE_TEXT
            && strtolower($this->getCharset()) != 'utf-8'
        ) {
        ...
        }
    ...
    }

[Slamdunk]

Hi, I faced this issue too. I'll work on this as soon the CI process run again (see #170).

Can you provide a raw message body with such attachments?

[dkop]

1.eml.tar.gz
Encoding of attachment is CP1251.
When receiving content of attachment using getDecodedContent() all russian chars changed to symbol 3F in hex.

[Slamdunk]

Thank you very much for the feedback, we'll look soon on it

[Slamdunk]

With #196 I can correctly see Это письмо отправлено автоматически [...] when using $message->getBodyText()

[dkop]

Problem with method $attachment->getDecodedContent() is still exist. Encoding in file is broken after saving it.

[dkop]

Please check attached screenshot. Attachment type is text and attachment has no encoding parameter.
Maybe here
if ($this->getType() === self::TYPE_TEXT
we should not check type, but check $this->disposition !== 'attachment' or $this->disposition === null

[Slamdunk]

Hi, the screenshot contains the current public release: the fix instead is present only in the develop branch, not yet released

[Slamdunk]

Version 1 has been released with the fix.