Rubocop pre-commit git hook

pre-commit

#!/bin/bash

# Execute Rubocop before committing; aborts commit if any offense is found.
# By ggaona

# Get files to be analyzed (all staged files with '.rb' or '.rake' extension;
# ignores 'schema.rb', migrations and deleted files)
STAGED_FILES=$(git diff --name-status --cached | grep -E '\.rb|\.rake' | grep -Ev 'D|schema.rb|migrate')

# Get total count of files to be analyzed
FILE_COUNT=$(printf "%s" "$STAGED_FILES" | grep -c "^")

# Continue to commit if there are no files to analyze
if [[ $FILE_COUNT -eq 0 ]]; then
  exit 0
fi

# Get new and modified files
FILES=$(printf "$STAGED_FILES" | grep -E 'A|M' | awk '{print $2}')

# Add renamed files
FILES="$FILES $(printf "$STAGED_FILES" | grep -E 'R' | awk '{print $3}')"

# Execute rubocop
echo "[RuboCop]"
rubocop --color $FILES

# Abort commit if offenses are found
if [ $? -ne 0 ]; then
  echo "Commit aborted"
  exit 1
fi