task.mk/docs/usage.md

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Usage

Task.mk will add access to a recipe help (also aliased to h). In order to use make help to you will need to add some custom comments to your Makefile.

Deliberately, I don't get names from recipes themselves. This not only greatly simplifies the parsing but add's some opportunity to customize the output. Such as to document wildcard or redundant recipes.

You can place these anywhere, but I recommend adding these notes directly above their relevant recipes. The format is ## <recipe> | <msg>

## build | build the project
.PHONY: build
build:
  ...

Now when you invoke make help it will parse these and generate your help output.

In addition to a generic help output you can expose some configuration settings with make vars. To do so define the variables you'd like to print with PRINT_VARS := VAR1 VAR2 VAR3.

In addition to the help and vars recipes you can use a custom make function to format your text for fancier output. For this there are two options depending on your needs tprint or tprint-sh. (tprint-sh is for use within a multiline sub-shell that has already been silenced, see the version-check rule of this project's Makefile for an example.)

To use tprint you call it with the builtin make call function. It accepts only one argument: an unquoted f-string literal. All strings passed to tprint have access to an object ansi or a for simplicity. This stores ANSI escape codes which can be used to style your text.

## build | compile the source
.PHONY: build
build:
  $(call tprint,{a.cyan}Build Starting{a.end})
  ...
  $(call tprint,{a.green}Build Finished{a.end})

See this projects make info for more examples of tprint.

To see the available colors and formatting(bold,italic,etc.) use the hidden recipe make _print-ansi.

Note: Any help commands starting with an underscore will be ignored. To view hidden tasks (or recipes in GNU Make land) you can use make _help.

In addition, you can use custom colors using the builtin ansi.custom or (a.custom) method. It has two optional arguments fg and bg. Which can be used to specify either an 8-bit color from the 256 colors. Or a tuple/list to define an RBG 24-bit color, for instance a.custom(fg=(5,10,255)). See this project's make info for an example.

Configuration

You can quickly customize some of the default behavior of task.mk by overriding the below variables prior to the -include .task.mk.

# ---- CONFIG ---- #
HEADER_STYLE ?= b_cyan
PARAMS_STYLE ?= b_magenta
ACCENT_STYLE ?= b_yellow
GOAL_STYLE ?= $(ACCENT_STYLE)
MSG_STYLE ?= faint
DIVIDER_STYLE ?= default
DIVIDER ?=HELP_SEP ?=# python f-string literals
EPILOG ?=
define USAGE ?=
{ansi.$(HEADER_STYLE)}usage{ansi.end}:
  make <recipe>

endef

To use a custom color for one of the predefined configuration variables specify only the custom method.

HEADER_STYLE = custom(fg=171,bg=227)

NOTE: HELP_SEP does not change the argument definitions syntax only the format of make help.

Advanced Usage: Embedded Python Scripts

You can take advantage of the builtin python script runner and write multi-line python scripts of your own. This is a simple example but a few lines of python in your Makefile may be easier than balancing sub-shells and strung together awk commands.

When make expands the function it will take the parameters passed to py and expand them. $(1) is the variable name and $(2) in this case is the implicit pattern from the rule. Pay attention to quotes. If you need to debug your python script, use DEBUG=1 when you run make and it will first print the script that will be piped to python.

define list_files_py
from pathlib import Path
print("files in $(2)")
print([f.name for f in (Path("$(2)").iterdir())])
endef

## list-% | use pathlib.Path to list files
list-%:
	$(call py,list_files_py,$*)

For what it's worth there is also a predefined function for bash (named tbash) as well should you need to accomplish something similar of more easily embedding your bash script rather than having to escape every line with a backslash.

define bash_script
figlet task.mk 2>/dev/null || echo 'no figlet :('
echo "This is from bash"
cat /etc/hostname
printf "%s\n" "$(2)"
endef
.PHONY: test-bash
test-bash:
	$(call tbash,bash_script,test bash multiline)