Rspec file benchmark zsh script

rspec_benchmark.sh

#!/usr/bin/env zsh
# rspec_benchmark.sh

set -e

if [[ $# -ne 2 ]]; then
  echo "Usage: $0 <spec_file> <number_of_runs>"
  echo "Example: $0 spec/features/some_feature/feature_spec.rb 5"
  exit 1
fi

file="$1"
runs="$2"

if [[ ! -f "$file" ]]; then
  echo "File not found: $file"
  exit 1
fi

if [[ "$runs" -lt 1 ]]; then
  echo "Number of runs must be at least 1."
  exit 1
fi

typeset -a times

for i in $(seq 1 $runs); do
  echo ""
  echo "$(printf '=%.0s' {1..60})"
  echo "Run $i of $runs"
  echo "$(printf '=%.0s' {1..60})"

  output=$(bundle exec rspec "$file" 2>&1)
  echo "$output"

  duration=$(echo "$output" | grep -oE 'Finished in [0-9]+\.?[0-9]*' | grep -oE '[0-9]+\.?[0-9]*')

  if [[ -n "$duration" ]]; then
    times+=("$duration")
    echo ">> Run $i completed in ${duration}s"
  else
    echo ">> Run $i: Could not parse timing from output."
  fi
done

count=${#times[@]}

if [[ "$count" -eq 0 ]]; then
  echo "\nNo timing data collected."
  exit 1
fi

sorted=($(echo "${times[@]}" | tr ' ' '\n' | sort -n))

stats=$(echo "${sorted[@]}" | tr ' ' '\n' | awk '
BEGIN { count = 0 }
{
  vals[NR] = $1
  sum += $1
  count++
  rounded = sprintf("%.1f", $1)
  freq[rounded]++
}
END {
  mean = sum / count

  if (count % 2 == 1) {
    median = vals[int(count / 2) + 1]
  } else {
    median = (vals[count / 2] + vals[count / 2 + 1]) / 2.0
  }

  range_val = vals[count] - vals[1]
  min_val = vals[1]
  max_val = vals[count]

  max_freq = 0
  for (k in freq) {
    if (freq[k] > max_freq) {
      max_freq = freq[k]
    }
  }
  mode_str = ""
  for (k in freq) {
    if (freq[k] == max_freq) {
      if (mode_str != "") mode_str = mode_str ", "
      mode_str = mode_str k "s"
    }
  }

  printf "MEAN=%.4f\n", mean
  printf "MEDIAN=%.4f\n", median
  printf "RANGE=%.4f\n", range_val
  printf "MIN=%.4f\n", min_val
  printf "MAX=%.4f\n", max_val
  printf "MODE=%s\n", mode_str
  printf "MODE_FREQ=%d\n", max_freq
}')

mean=$(echo "$stats" | grep '^MEAN=' | cut -d= -f2)
median=$(echo "$stats" | grep '^MEDIAN=' | cut -d= -f2)
range_val=$(echo "$stats" | grep '^RANGE=' | cut -d= -f2)
min_val=$(echo "$stats" | grep '^MIN=' | cut -d= -f2)
max_val=$(echo "$stats" | grep '^MAX=' | cut -d= -f2)
mode=$(echo "$stats" | grep '^MODE=' | cut -d= -f2)
mode_freq=$(echo "$stats" | grep '^MODE_FREQ=' | cut -d= -f2)

echo ""
echo "$(printf '=%.0s' {1..60})"
echo "RESULTS"
echo "$(printf '=%.0s' {1..60})"

for i in $(seq 1 $count); do
  echo "  Run $i: ${sorted[$i]}s"
done

echo "$(printf -- '-%.0s' {1..40})"
echo "  Mean:   ${mean}s"
echo "  Median: ${median}s"
echo "  Mode:   ${mode} (rounded to 0.1s, appeared ${mode_freq}x)"
echo "  Range:  ${range_val}s (${min_val}s – ${max_val}s)"
echo "$(printf '=%.0s' {1..60})"