tasklog

#!/usr/bin/env bash
#
# tasklog
#   displays changes since birth for the given task
#
# scott@smemsh.net
# https://github.com/smemsh/taskwtools/
# https://spdx.org/licenses/GPL-2.0
#

`type -P task` \
rc._forcecolor=0 \
rc.color=0 \
rc.detection=0 \
rc.defaultwidth=0 \
rc.journal.info=1 \
"$@" \
2>&1 \
| tac \
| grep -m1 -B$(((2 << 31) - 1)) ^---- \
| tac \
| tail -n +2 \
| grep -v ^$ \
| gawk -r '
BEGIN {
	FS = "\n"
	RS = "(^|\n)[[:digit:]-]{10} [[:digit:]:]{8} "
	lasttime = ""
}
{
	sub("^[[:space:]]+", "", RT)
	sub("[[:space:]]+$", "", RT)
	time = lasttime  # RT of previous is timestamp for this line
	lasttime = RT
	if (!NF) next  # input begins with RT so first $0 is empty
}
{
	for (i = 1; i <= NF; i++) {
		changeline = $i
		if (!changeline) continue # last RT does not consume newline
		sub("^[[:space:]]+", "", changeline)
		printf("%s %s\n", time, changeline)
	}
}
'