How to automatically generate a Makefile help command

I recently found this article online, that explains how to setup a make help target that will automatically parse the Makefile for comments and display a nicely formatted help command.

It parses:

install: ## Install npm dependencies for the api, admin, and frontend apps
    @echo "Installing Node dependencies"
    @npm install

install-dev: install ## Install dependencies and prepared development configuration
    @./node_modules/.bin/selenium-standalone install
    @cp -n ./config/development.js-dist ./config/development.js | true

run-frontend-dev: webpack.PID ## Run the frontend and admin apps in dev (using webpack-dev-server)

Into:

install              Install npm dependencies for the api, admin, and frontend apps
install-dev          Install dependencies and prepared development configuration
run-frontend-dev     Run the frontend and admin apps in dev (using webpack-dev-server)

But for some reason I can't get it working (on OSX at least). With this target:

help: ## Show the help prompt.
  @grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'

When I run:

make help

I just get:

$ make help
make: Nothing to be done for `help'.

I've tried all of the different solutions from the comments in the article too, but nothing seems to work. What am I doing wrong?

Also, what would a variation on the script be that would allow comments to be placed on a line before the target, instead of after it. Like so:

# Build the source files with Babel.
build: $(shell find lib)
    @rm -rf build
    @mkdir -p build
    @$(babel) lib $(babel_options)

# Seed the database with fake data.
db-fake:
    @$(run) node bin/run-sql fake

Here is the full Makefile in question:

# Options.
DEBUG ?=
SOURCEMAPS ?= true
WATCH ?=

# Variables.
bin = ./node_modules/.bin
tests = $(shell find test/routes -depth 1)
shorthand-tests = $(patsubst test/routes/%.js,test-%,$(tests))

# Binaries.
babel = $(bin)/babel
mocha = $(bin)/mocha
node = node
nodemon = $(bin)/nodemon
run = heroku local:run

# Babel options.
babel_options = \
    --out-dir build \
    --copy-files

# Sourcemaps?
ifneq ($(SOURCEMAPS),false)
babel_options += --source-maps
endif

# Watch?
ifdef WATCH
babel_options += --watch
endif

# Development?
ifneq ($(NODE_ENV),production)
node = $(nodemon)
endif

# Debug?
ifdef DEBUG
node += debug
mocha += debug
endif

# Default.
default: help ## Default.

# Build the source files with Babel.
build: $(shell find lib) ## Build the source files with Babel.
    @rm -rf build
    @mkdir -p build
    @$(babel) lib $(babel_options)

# Seed the database with fake data.
db-fake: ## Seed the database with fake data.
    @$(run) node bin/run-sql fake

# Reset the database, dropping everything and the creating again.
db-reset: ## Reset the database, dropping everything and the creating again.
    @$(run) node bin/run-sql drop
    @$(run) node bin/run-sql create

# Seed the database with test data.
db-seed: ## Seed the database with test data.
    @$(run) node bin/run-sql seed

# Show the help prompt.
help: ## Show the help prompt.
  @awk '/^#/{c=substr($0,3);next}c&&/^[[:alpha:]][[:alnum:]_-]+:/{print substr($1,1,index($1,":")),c}1{c=0}' mm.mk | column -s: -t

# Open the PSQL interface.
psql: ## Open the PSQL interface.
    @psql contentshq

# Run the development server.
server: ## Run the development server.
    @$(run) $(node) bin/api

# Start the local postgres server.
start: ## Start the local postgres server.
    @pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start

# Stop the local postgres server.
stop: ## Stop the local postgres server.
    @pg_ctl -D /usr/local/var/postgres stop -s -m fast

# Run all of the tests.
test: ## Run all of the tests.
    @$(run) $(mocha) $(tests)

# Run specific route tests.
$(shorthand-tests): ## Run specific route tests.
    @$(run) $(mocha) test/routes/$(subst test-,,$@).js

# Watch the source files with Babel.
watch: ## Watch the source files with Babel.
    @WATCH=true $(MAKE) build

# Phony targets.
.PHONY: help
.PHONY: test
.PHONY: watch

Solution

Here's a little awk script which will handle the case where the comment comes before the target name. I used column to put the text into columns, but you could do it in awk using a printf (and, if you wanted, adding the console codes to colorize the output); the advantage of using column is that it works out the column width automatically.

You'd insert it into the Makefile in the same way:

.PHONY: help

# Show this help.
help:
    @awk '/^#/{c=substr($$0,3);next}c&&/^[[:alpha:]][[:alnum:]_-]+:/{print substr($$1,1,index($$1,":")),c}1{c=0}' $(MAKEFILE_LIST) | column -s: -t