A handy Xcode run script that applies SwiftLint only to new Swift codebase changes

swiftlint.sh

#!/bin/bash

# Parameters
source="$(pwd)/$1"                          # Track folder source where diffs are checked
index=$2                                    # Track diff remote
project_root=${0%/*}                        # Track project root folder
swiftlint_path='Pods/SwiftLint/swiftlint'   # Track SwiftLint path

# Parameter check
if [[ $# < 1 ]]; then
  echo $(pwd)
  echo "usage: $0 SOURCE INDEX"
  echo 'SOURCE -> Project source code folder'
  echo 'INDEX -> git diff comparison index. Defaults to "origin/master"'
  exit 1
elif [[ $# == 1 ]]; then
  index=origin/master
fi

cd $project_root
# Iterate through each modified file
while read file; do
  hunkCount=0                               # Track number of hunks
  hunkLines=()                              # Track each hunk range [start, end] = [hunkLines[i*2], hunkLines[i*2+1]]
  # Iterate through each git diff hunk
  while read hunk; do
    hunkCount=$((hunkCount+1))
    hunkLines+=(${hunk%%+*})                # Add hunk start line
    hunkLines+=($(echo $hunk | bc))         # Add hunk end line
  done< <(git diff -U0 $file | egrep '@@' | cut -d ' ' -f 3 | sed -e 's|+||' -e 's|,|+|')
  # Iterate through each violation from SwiftLint
  while read violation; do
    line=$(echo $violation | cut -d : -f 2) # Track violation line number
    # Iterate through each hunk range to see if violation applies
    for i in $(seq 0 $((hunkCount-1))); do
      # Check if violation is in range of hunk
      if [ "$line" -ge "${hunkLines[i*2]}" ] && [ "$line" -le "${hunkLines[i*2+1]}" ]; then
        # Violation output format is automatically recognized by Xcode
        echo $violation
        # Check if the violation contains an error, and exit immediately
        if [[ $violation == *" error: "* ]]; then exit 1; fi
        break
      fi
    done
  done< <($swiftlint_path lint --path $file)
done< <(git diff --name-only --diff-filter=d $index | egrep "${source#$(pwd)/}" | egrep '.swift$')