Enable 'termbidi' for gnome-terminal 3.34

[hedayat]

Gnome terminal in gnome 3.34 supports bidi text rendering/typing. It'd be nice if 'termbidi' is enabled on it automatically.

[brammool]

Hedayat Vatankhah wrote:

Gnome terminal in gnome 3.34 supports bidi text rendering/typing. It'd be nice if 'termbidi' is enabled on it automatically.

Does this terminal always work in this mode, or is it something that can be enabled and disabled? How do we check the terminal is at this version?

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[hedayat]

It always works. Or... at least in Fedora it is enabled by default as far as I see (I've not done any special configuration).

But I don't know how to check the version or if it is possible at all; but I hope so. :( ...

OK, I found it! It is actually not about gnome-terminal alone, it is about any VTE based terminal (I'm not aware of any other though :P). Anyway, you can check VTE_VERSION environment variable.
My VTE_VERSION is 5800, (vte version 0.58.0). But according to https://mail.gnome.org/archives/gnome-announce-list/2019-July/msg00003.htmlhttps://mail.gnome.org/archives/gnome-announce-list/2019-July/msg00003.html, it should work on vte >= 0.57.3, which is probably VTE_VERSION >= 5730.

[avidseeker]

More generally, I think this feature request falls under the title of "Automatic detection for termbidi". Vim Arabic shaping support via :set arabicshape is currently enabled by default regardless of the terminal. This causes the problems explained in #9761.

It made sense to set this option the default when most terminals did not have shaping support and it was up to the console applications to provide proper rendering. Currently, however, most terminals already support Unicode shaping, so it would be better for Vim to be smarter instead of assuming the default.

I think there should be some library function (perhaps wcwidth?) that could inform Vim whether the terminal has letter shaping capabilities.