Reject an empty operand in the `cd` built-in

[magicant]

POSIX.1-2024 requires that the cd built-in fail if given an empty operand as in cd ''.

Currently, cd -L '' is effectively equivalent to cd -L "$PWD/", which usually results in successfully not changing the working directory.

• Update the implementation to add a check for an empty operand. The exit status should be 5 on error.
• Update the test scripts.
• Update the user manual.
• Update the NEWS.

[Connor-GH]

Currently, cd -L '' is effectively equivalent to cd -L "$PWD/", which usually results in successfully not changing the working directory.

yash/path.c

Line 1264 in 1a3525d

assert(!logical || origpwd != NULL);

This is what you need to change, I believe.

Also, your code quality is amazing. This is the best shell implementation I have ever seen.

[c0d3-br3ak9r]

Hi, I'd like to work on this!

[c0d3-br3ak9r]

Hi,

I've raised a PR. Pls do let me know if any changes are required.

Btw, I have a doubt. Why is Ngt used while calling xerror?

yash/path.c

Line 1239 in f036450

xerror(0, Ngt("$PWD has an invalid value"));

Because all that does is substitute with the literal itself in both the cases

yash/common.h

Lines 34 to 40 in f036450

	#if HAVE_GETTEXT
	# define gt(MSGID) ((const char *) gettext(MSGID))
	# define Ngt(MSGID) MSGID
	#else
	# define gt(MSGID) MSGID
	# define Ngt(MSGID) MSGID
	#endif

[magicant]

Ngt is a dummy macro that is parsed by the xgettext utility to extract localizable messages from the source code.