Add test for iconv_mime_encode() for preference input-charset and output-charset

[juan-morales]

The test is for enhancing the code coverage on function iconv_mime_encode().

At the moment coverage looks like:

After the test looks like:

This is the first time ever I do this, and hopefully I am following the process correctly.

Thanks in advance.

[cmb69]

Thank you for the PR!

[cmb69]

@kocsismate, had it been considered to throw ValueErrors for these conditions (there are several related ones in the iconv.c):

php-src/ext/iconv/iconv.c

Lines 1996 to 1998 in bbc0c4c

	if (Z_STRLEN_P(pzval) >= ICONV_CSNMAXLEN) {
	php_error_docref(NULL, E_WARNING, "Encoding parameter exceeds the maximum allowed length of %d characters", ICONV_CSNMAXLEN);
	RETURN_FALSE;

Might have been a good idea, if we also would have exposed ICONV_CSNMAXLEN; users could then check the length upfront, if they're even handling user input.

[juan-morales]

@kocsismate, had it been considered to throw ValueErrors for these conditions (there are several related ones in the iconv.c):

php-src/ext/iconv/iconv.c

Lines 1996 to 1998 in bbc0c4c

	if (Z_STRLEN_P(pzval) >= ICONV_CSNMAXLEN) {
	php_error_docref(NULL, E_WARNING, "Encoding parameter exceeds the maximum allowed length of %d characters", ICONV_CSNMAXLEN);
	RETURN_FALSE;

Might have been a good idea, if we also would have exposed ICONV_CSNMAXLEN; users could then check the length upfront, if they're even handling user input.

While working on the test I thought exactly that, ... that would be good to expose such a constant to user context.

[juan-morales]

I enhanced the test to cover a little bit more. I think is good to keep them in same test as is testing basically identically things in the same function.

Before test

After test

[juan-morales]

all changes done

[juan-morales]

@cmb69 the change still looks with the "Changes requested" label ... can you take a look? I think is because of your review. I also dont know if that is important or not to consider my change to be merge.

Thanks in advance.

[cmb69]

Thank you!