createDiffs.sh bash script to show differences in files between two folders using the *nix command diff

createDiffs.sh

#!/bin/bash

set -e
set -u
set -o pipefail

SOURCE_PATH=$1
DESTINATION_PATH=$2

sourceFiles=$(ls -l ${SOURCE_PATH}/ | wc -l)
echo "Number of files in source folder ${SOURCE_PATH}: ${sourceFiles}"
destinationFiles=$(ls -l ${DESTINATION_PATH}/ | wc -l)
echo "Number of files in destination folder ${DESTINATION_PATH}: ${destinationFiles}"

echo "Enlisting declarations that have changed"
rm which_declarations_differ.txt || true
diff -q --suppress-common-lines -y -d --strip-trailing-cr \
     "${SOURCE_PATH}" "${DESTINATION_PATH}" > which_declarations_differ.txt || true

echo "Enlisting differences between the declarations (before and after)"
rm differences_between_changes.txt || true
touch differences_between_changes.txt
for filenameWithPath in ${SOURCE_PATH}/*; do
	filenameOnly="$(basename ${filenameWithPath})"
	#echo "Searching for ${filenameOnly} in which_declarations_differ.txt"
	foundFile="$(grep ${filenameOnly} which_declarations_differ.txt || true)"
	if [[ ! -z "${foundFile}" ]]; then
		echo "Found ${filenameOnly} in which_declarations_differ.txt"
		rm each_diff.txt || true
		diff --suppress-common-lines -y -d --strip-trailing-cr "${SOURCE_PATH}/${filenameOnly}" "${DESTINATION_PATH}/${filenameOnly}" > each_diff.txt || true
		if [[ -s each_diff.txt ]]; then
			echo "" >> differences_between_changes.txt
			echo "Comparing ${SOURCE_PATH}/${filenameOnly} and ${DESTINATION_PATH}/${filenameOnly}" >> differences_between_changes.txt
			cat each_diff.txt >> differences_between_changes.txt
			echo "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" >> differences_between_changes.txt
			echo "" >> differences_between_changes.txt
        fi
    fi
done