Enhance Makefile by changing some Make defaults (#54)

.gitignore

@@ -88,3 +88,5 @@ venv.bak/
 .mypy_cache/
 .dmypy.json
 dmypy.json
+
+tmp/

Makefile

@@ -1,35 +1,57 @@
 
-SRC:=rfd
+SRC := rfd
+SHELL := bash
+.ONESHELL:
+.SHELLFLAGS := -eu -o pipefail -c
+.DELETE_ON_ERROR:
+MAKEFLAGS += --warn-undefined-variables
+MAKEFLAGS += --no-builtin-rules
 
-.PHONY: build
+
+ifeq ($(origin .RECIPEPREFIX), undefined)
+  $(error This Make does not support .RECIPEPREFIX. Please use GNU Make 4.0 or later)
+endif
+.RECIPEPREFIX = >
+
+## build: Build a tar.gz of the python package
 build:
-	rm -rf dist/
-	python setup.py sdist
+> rm -rf dist/
+> python setup.py sdist
+.PHONY: build
 
-.PHONY: push_test
-push_test:
-	twine upload -r testpypi dist/*.tar.gz
-
-.PHONY: push_prod
-push_prod:
-	twine upload dist/*.tar.gz
-
-.PHONY: precommit
-precommit: ## Run pre-commit
-	pre-commit run \
+## precommit: Run all pre-commit hooks
+precommit:
+> pre-commit run \
  --all-files \
  --show-diff-on-failure
+.PHONY: precommit
 
-.PHONY: lint
+## lint: Run static analysis on the code
 lint:
-	pylint $(SRC)
+> pylint $(SRC)
+.PHONY: lint
 
+## test: Run all unit tests
+test: tmp/.tests-passed.sentinel
 .PHONY: test
-test:
-	pytest -v
 
-.PHONY: pr
+# Tests - re-ran if any file under src has been changed since tmp/.tests-passed.sentinel was last touched
+tmp/.tests-passed.sentinel: $(shell find ${SRC} -type f)
+> mkdir -p $(@D)
+> pytest -v
+> touch $@
+
+## pr: Run pre-commit, lint and test
 pr: precommit lint test
+.PHONY: pr
 
-.PHONY: ci
 ci: lint test
+.PHONY: ci
+
+## help: Print this help message
+help:
+> @echo "Usage:"
+> @echo
+> @sed -n 's/^##//p' ${MAKEFILE_LIST} | column -t -s ':' |  sed -e 's/^/ /' | sort
+> @echo
+.PHONY: help