switchToPreact.sh

# Use preact
# Switch a react project to using preact if its isn't using it already.
#
# EX: grep -rl "preact-compat" ./node_modules/react-scripts/config/
# EX: find ./node_modules/react-scripts/config/*.config.* -type f -exec sed -i "s/alias: {/alias: {\n\t\t\t\'react\': \'preact-compat\',\n\t\t\t\'react-dom\': \'preact-compat\',/gi" {} \;

searchString=${1:-preact-compat}
filePattern=${2:-./node_modules/react-scripts/config/}

replaceString="alias: {"
newString="alias: {\n\t\t\t\'react\': \'preact-compat\',\n\t\t\t\'react-dom\': \'preact-compat\',"

SEARCH="$(grep -rl "$searchString" $filePattern)"
echo "${SEARCH}"

if [ ! "${SEARCH}" ]
  then
    echo "preact was not detected, adding it as a webpack config alias..."

    REPLACE="$(find $filePattern -type f -exec sed -i "s/$replaceString/$newString/gi" {} \;)"
    echo "${REPLACE}"
fi