BUG #16236: Invalid escape encoding

The following bug has been logged on the website:

Bug reference:      16236
Logged by:          Stéphane Campinas
Email address:      stephane.campinas@gmail.com
PostgreSQL version: 12.1
Operating system:   linux 5.4.14
Description:

Hi,

From the documentation [0] about the encode function, the "escape" format
should "convert zero bytes and high-bit-set bytes to octal sequences (\nnn)
and doubles backslashes."
However, executing "select encode(E'aaa\bccc', 'escape');" outputs
"aaa\x08ccc", although according to the documentation I should get
"aaa\010ccc". This was found in [1] while mimicking the output of encode,
where you can get more details.

Cheers,

[0] https://www.postgresql.org/docs/12/functions-string.html
[1] https://github.com/crate/crate/pull/9540