jj-fzf: assert that bash supports interactive mode with readline editing

Some bash builds reportedly lack interactive readline editing (Nix stdenv).

Signed-off-by: Tim Janik <[email protected]>

jj-fzf

@@ -71,6 +71,7 @@ gawk --version | grep -Fq 'GNU Awk' || die "failed to find 'gawk' in \$PATH (GNU
 version0d() { gawk 'BEGIN{FPAT="[0-9]+"} {printf("%04d.%04d.%04d.%04d.%04d\n",$1,$2,$3,$4,$5);exit}' <<<" $* "; }
 versionge() { test "$(version0d "$2")a" '<' "$(version0d "$1")b"; }
 versionge "$(bash --version)" 5.1.16 || die "failed to find 'bash' version 5.1.16 in \$PATH"
+[[ `set -o` =~ emacs ]] || die "the 'bash' executable lacks interactive readline support"
 versionge "$(jj --version --ignore-working-copy)" 0.24 || die "failed to find 'jj' version 0.24.0 in \$PATH"
 versionge "$(fzf --version)" 0.43 || die "failed to find 'fzf' version 0.43.0 in \$PATH" # 0.43.0 supports offset-up
 sed --version 2>/dev/null | grep -Fq 'GNU sed' && gsed() { sed "$@"; } && export -f gsed ||