Xcode - Run Script - Create Input & Output file list of git-changed files to optimise build process.

input_output_list_for_changed_files.sh

#!/bin/sh

# Read more at:
# https://stackedheaps.com/2023/07/02/optimise-xcode-builds-with-input-output-file-lists

# Script Arguments:
# $1 = xcfilelist name without extension. 
# 	Example: ChangedFiles
# $2 = Optional Output directory
#	Path relative to $SRCROOT for saving xcfilelist. 
#	By default, file will be saved in projects root directory

# **********************************************************************************

# Create xcfilelist for the changed file.

XC_FILE_LIST_NAME=$1
OUTPUT_DIRECTORY=$2

if [ ! -z $OUTPUT_DIRECTORY ]; then 
    PROJECT_XC_FILE=$SRCROOT/$OUTPUT_DIRECTORY/$XC_FILE_LIST_NAME.xcfilelist
else
    PROJECT_XC_FILE=$SRCROOT/$XC_FILE_LIST_NAME.xcfilelist
fi

BUILD_XC_FILE=$DERIVED_FILE_DIR/$XC_FILE_LIST_NAME.xcfilelist
OUTPUT_FILE=$DERIVED_FILE_DIR/$XC_FILE_LIST_NAME.txt

# Find files and add the contents to xcfilelist.
git --no-pager diff --name-only | sed -e 's#^#$(SRCROOT)/#;' > $BUILD_XC_FILE

# Compare SRCROOT file with DERIVED_FILE_DIR file. Copy if anything has changed.
cmp --silent $PROJECT_XC_FILE $BUILD_XC_FILE || cp -f $BUILD_XC_FILE $PROJECT_XC_FILE

# Create an output file
touch $OUTPUT_FILE

# **********************************************************************************