Retry until fail script

README.md

Until fail

Retry a command until it fails.

Debugging brittle specs is annoying and time consuming work. Let's automate finding those brittle specs by retrying them until they fail.

Accompanying blog post.

Usage

$ until-fail true
# Will repeat forever

$ until-fail false
# Fails at the first iteration and break out of the retry loop

$ until-fail ruby -e "(rand(0..1) == 1) ? (puts 'failed'; exit(1)) : (puts 'success')"
# Fails randomly and breaks out of the retry loop when it fails

Installation

• Open a directory that's in your local $PATH. (See the list with echo $PATH in your terminal.)
• Download the until-fail file from the gist. (Click the "Raw" button on the until-fail file.
• Create a until-fail file in the open directory and paste in the until-fail file contents.
• Make the file executable with chmod +x until-fail.
• Now call the excutable with a command.

until-fail

#!/bin/bash

# Retry a command until it fails
#
# Usage:
#
#   $ until-fail true
#   # Will repeat forever
#
#   $ until-fail false
#   # Fails at the first iteration and breaks out of the retry loop
#
#   $ until-fail ruby -e "rand(0..1) == 1 ? (puts 'failed'; exit(1)) : (puts 'success')"
#   # Fails randomly and breaks out of the retry loop when it fails

if [[ -z "$*" ]]; then
  echo "ERROR: No command given to retry"
  exit 1 # Error status
fi

i=0
while true; do
  i=$((i + 1))
  echo "================================================================================"
  echo "Retry #$i: $*"
  echo
  # Run command and exit only if it fails
  if ! "$@"; then
    echo
    echo "ERROR: Failure on retry #$i"
    exit 1 # Exit loop with error status
  fi
done