Crystal Makefile which runs tests when files change

Makefile

# Requires inotify-tools to be installed. On Ubuntu / Debian:
# sudo apt install inotify-tools
CRYSTAL=crystal
TEST_ARGS=--chaos --parallel 4 --verbose
SPEC_ARGS=--order=random --error-on-warnings --verbose

WATCH=src/**/*.cr spec/**/*.cr test/**/*.cr
# The make rule to use when running tests. Either spec or test
TEST_RULE=test

.PHONY: spec watch test

spec:
	crystal spec $(SPEC_ARGS)

test:
	bash -c 'shopt -s globstar; $(CRYSTAL) run test/**/*_test.cr -- $(TEST_ARGS)'

watch:
	bash -c 'shopt -s globstar; while true; do inotifywait -e close_write $(WATCH); $(VERBOSE) make $(TEST_RULE); done'