bash-it takes rather a while to startup, around 0.5 seconds on my
laptop. After a bit of timing it appears the majority of the time is
spent in themes/colors.theme.bash. The reason for that is the fancy
abstraction layers that use $(). For example, consider this code:
red="$(color reset red)"
It will go through 9 forkexecs to evaluate:
red="$(color reset red)"
"$(__color_parse make_ansi reset red)"
"$(__make_ansi reset red)"
"\[\e[$(__reset red)m\]"
"\[\e[0;$(__red)m\]"
"\[\e[0;$(__color red)m\]"
"\[\e[0;$(__color_normal_fg $(__color_red))m\]"
"\[\e[0;$(__color_normal_fg 1)m\]"
"\[\e[0;31m\]"
With all the variables in colors.theme.bash, this adds up to hundreds of
forks:
$ strace -f bash ./colors.theme.bash 2>&1 | grep clone | wc -l
649
The solution is to replace the function with its result:
-red="$(color reset red)"
+red='\[\e[0;31m\]'
This is safe, since colors.theme.bash never calls external functions or
takes any input. So, its result can be safely hard-coded.
This improves startup time dramatically. Try adding "time" to your .bashrc:
# Load Bash It
time source $BASH_IT/bash_it.sh
before:
real 0m0.462s
user 0m0.100s
sys 0m0.399s
after:
real 0m0.150s
user 0m0.091s
sys 0m0.064s
When using `set -x` with a `$PS4` variable which calls a external
command (e.g. `PS4='+ $(true)'`) the color functions end in a infite
loop.
The solution is `shift` the arguments unconditionally in the color
funtions.
This fixes#546
Daijiro Wachi
Brian Malehorn
Hector Rivas Gandara
Eitan Adler
Beren Minor
Travis Swicegood
JFSIII
Robert R Evans