The following reproducer causes a spurious syntax error:
foo="`: "("`"
The nested double quotes are not recognised correctly, causing a
syntax error at the '('. Removing the outer double quotes (which
are unnecessary) is a workaround, but it's still a bug as every
other shell accepts this. This bug has been present since the
original Bourne shell.
src/cmd/ksh93/sh/lex.c: sh_lex(): case S_QUOTE:
- If the current character is '"' and we're in a `...` command
substitution (ingrave is true), then do not switch to the old
mode but keep using the ST_QUOTE state table.
Thanks to @JohnoKing for the report and to @atheik for the fix.
Co-authored by: Martijn Dekker <martijn@inlv.org>
Resolves: https://github.com/ksh93/ksh/issues/352