stopwatch

#!/bin/bash

# Usage: stopwatch tests.file > output.file
# 
# Measures the execution time (in seconds) of every possible combination of
# arguments in the testset file and echoes the results in columnated format
# to standard output.  Total execution time is echoed to standard error.
# The leftmost column is blank if the process in question completed without
# issue and contains a '!' if it exited with a non-zero status.
# 
# The testset file must contain one parameter per line, with no spaces
# within parameters.  A line starting with ::: marks the start of a new
# parameter dimension.  If you need column headers in the output, you can
# follow the :::'s with whitespace and the dimension name.  (The astute reader
# may have observed that this file looks suspiciously like an argument list to
# GNU parallel, and that is exactly how it is used.)  Lines may be commented
# by prefixing them with a #.
# 
# Example: stopwatch testset 1> results.csv 2> totaltime

dimensions=$(grep -c ^::: "$1")
headers=($(grep ^::: "$1"| cut -c 5-))

format="%c"
for lineno in $(grep -n ^::: "$1" | grep -oP '\d+'); do
    maxlen=0
    for word in $(sed -n "$lineno,/^:::/p" "$1" | head -n-1 | grep -v '^#'); do
        if [ ${#word} -gt $maxlen ] ; then
            maxlen=${#word}
        fi
    done
    format="$format  %-${maxlen}s"
done
format="$format  %7s  %7s\n"

if [ ${#headers[@]} -eq $dimensions ] ; then
    headerflag='--header :'
    printf "$format" '?' "${headers[@]}" real user
    args=$(for x in "${headers[@]}"; do echo -n "{$x} "; done)
else
    args=$(seq -s ' ' -f '{%0.0f}' $dimensions)
fi

time parallel --max-procs 1 $headerflag "
    TIMEFORMAT='%3E %3U'
    result=\$((time $args 1>/dev/null 2>/dev/null) 2>&1)
    [ \$? -eq 0 ] && status=' ' || status='!'
    printf '$format' \"\$status\" $args \$result
" $(grep -v '^#' "$1")