fzf function and key binding for searching through environment bash variables

Question

After inspecting fzf/shell/key-bindings.bash I came up with the following, to be put in my ~/.bashrc:

fzf_get_env_vars() {
 local cmd opts selected
 cmd='command env | command sed "s/=.*//;s/^/$/"'
 opts="--height ${FZF_TMUX_HEIGHT:-40%} --bind=ctrl-z:ignore --reverse $FZF_DEFAULT_OPTS $FZF_CTRL_T_OPTS -m"
 selected="$(eval "$cmd" \
 | FZF_DEFAULT_OPTS="$opts" $(__fzfcmd) "$@" \
 | while read -r item; do
 printf '%s ' "$item"
 done
 )"
 READLINE_LINE="${READLINE_LINE:0:$READLINE_POINT}$selected${READLINE_LINE:$READLINE_POINT}"
 READLINE_POINT=$(( READLINE_POINT + ${#selected} ))
}
# I'm a vi-mode user, so no need for emacs mapping
bind -m vi-command -x '"\ee": fzf_get_env_vars'
bind -m vi-insert -x '"\ee": fzf_get_env_vars'

Major changes I've applied to what I've seen in the linked files are

• I've not split the function that calls fzf and retrieves the user-selected values from the function reassinging READLINE_LINE and READLINE_POINT;
• given the inputs are variable names, I think not escaping (i.e. '%s ' instead of '%q ') is safe,
• which in turns also allows me to prepend $ (via the second s command in the sed script) without it being escaped.

ShellCheck detects no issues with the code.

Answer 1

It's worth avoiding eval if possible.

Given your code, without the eval I came up with this:

fzf_sed_env_vars_cmd() {
 builtin command env |
 builtin command awk -F'=' '{printf "$%s\n", 1ドル}'
 # builtin command sed "s/=.*//;s/^/$/"'
}
fzf_get_env_vars() {
 builtin local opts selected
 opts="--height ${FZF_TMUX_HEIGHT:-40%} --bind=ctrl-z:ignore --reverse $FZF_DEFAULT_OPTS $FZF_CTRL_T_OPTS -m"
 selected="$( ##: Look Mah, No Eval!!! :-)
 fzf_sed_env_vars_cmd |
 FZF_DEFAULT_OPTS="$opts" $(__fzfcmd) "$@" |
 while builtin read -r item; do
 builtin printf '%s ' "$item"
 done
 )"
 READLINE_LINE="${READLINE_LINE:0:$READLINE_POINT}$selected${READLINE_LINE:$READLINE_POINT}"
 READLINE_POINT=$(( READLINE_POINT + ${#selected} ))
}
# I'm a vi-mode user, so no need for emacs mapping
builtin bind -m vi-command -x '"\ee": fzf_get_env_vars'
builtin bind -m vi-insert -x '"\ee": fzf_get_env_vars'

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