nixpkgs/pkgs/build-support/rust/build-rust-crate/log.nix
2020-08-09 17:47:12 +10:00

59 lines
1.7 KiB
Nix

{ lib }:
let echo_colored_body = start_escape:
# Body of a function that behaves like "echo" but
# has the output colored by the given start_escape
# sequence. E.g.
#
# * echo_x "Building ..."
# * echo_x -n "Running "
#
# This is more complicated than apparent at first sight
# because:
# * The color markers and the text must be print
# in the same echo statement. Otherise, other
# intermingled text from concurrent builds will
# be colored as well.
# * We need to preserve the trailing newline of the
# echo if and only if it is present. Bash likes
# to strip those if we capture the output of echo
# in a variable.
# * Leading "-" will be interpreted by test as an
# option for itself. Therefore, we prefix it with
# an x in `[[ "x$1" =~ ^x- ]]`.
''
local echo_args="";
while [[ "x$1" =~ ^x- ]]; do
echo_args+=" $1"
shift
done
local start_escape="$(printf '${start_escape}')"
local reset="$(printf '\033[0m')"
echo $echo_args $start_escape"$@"$reset
'';
echo_conditional_colored_body = colors: start_escape:
if colors == "always"
then (echo_colored_body start_escape)
else ''echo "$@"'';
in {
echo_colored = colors: ''
echo_colored() {
${echo_conditional_colored_body colors ''\033[0;1;32m''}
}
echo_error() {
${echo_conditional_colored_body colors ''\033[0;1;31m''}
}
'';
noisily = colors: verbose: ''
noisily() {
${lib.optionalString verbose ''
echo_colored -n "Running "
echo $@
''}
$@
}
'';
}