Bug: RTL-in-LTR texts aren't drawn correctly even with bidi enabled

[haashemi]

The writer package highly depends on Harfbuzz, which doesn't support bi-directional texts out of the box (documented here). Thus, the writer has to do the bidi processing itself.

On LTR-in-RTL texts, it just reverses the LTR strings, and everything seems to be fine. (at least with English and numbers)

But the main problem comes when you're trying to write an RTL word in LTR text. Not enabling Bidi results in the worst scenario, but enabling Bidi should work as it also reverses it (theorically!), but it doesn't as letters are not attached to each other and Harfbuzz can't choose the right unicodes for each letter. Here's how it draws with and without Bidi enabled:

The text should be: "Testing راست نویسی."