Help

The focus here is on the help target and some other targets are covered so you can see what kind of format is works against in that file.

Samples

Basic

Find lines starting with lowercase letters or comments. This excludes .HOOKS and any constants (typicall set using uppercase). This excludes empty lines, so the output is tightly packed.

• Makefile

    h help:
        @grep ^[a-z#]' Makefile
  

If you need to ignore an export like export FOO := 'bar' by requiring certain characters (lowercase letters, spaces or hyphens) repeated up to a colon and using extended egrep.

• Makefile

    h help:
        @egrep '^[a-z -]+:' Makefile
  

If you want non-indented comments as well, add this to the start: ^#|.

This pattern does not care if there is anything after the colon.

Or maybe it is cleaner to ignore export rather.

Not indented

Print lines that are not indented (targets and comments) or empty (so that empty lines add space between commands).

• Makefile

    h help:
        @egrep '^\S|^$$' Makefile
  

Include echo lines

If you use @echo within your targets, you can incldue them.

Includes left-aligned, empty lines and echo lines.

• Makefile

    help:
        @egrep '(^\S)|(^$$)|\s+@echo' Makefile
  

Detailed

Copied from Poetry’s Makefile.

This is complex - I don’t know why. I haven’t tested yet but maybe something here is useful.

• Makefile

    list:
        @sh -c "$(MAKE) -p no_targets__ | \
            awk -F':' '/^[a-zA-Z0-9][^\$$#\/\\t=]*:([^=]|$$)/ {\
                split(\$$1,A,/ /);for(i in A)print A[i]\
            }' | grep -v '__\$$' | grep -v 'make\[1\]' | grep -v 'Makefile' | sort"
    # required for list
    no_targets__:
  
  

Two column help

This will sort targets, split into two columns and add colors. It expects a description to come after the command with a double hash.

• Makefile

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

Sample output (the left column is colored blue).

help                           Show the commands and help
install                        Install all dependencies

Some improvements on above

If you want to support an alias line instead of ignoring completely, then add a space in the [] regex piece.

s serve                        Start dev server

If you want to support targets without comments, make # optional with #?#?. Or don’t require them at all.

Result pattern:

'^[a-zA-Z_ -]+:'

List targets and descriptions

• Makefile

    help: ## List targets & descriptions
        @cat Makefile* \
            | grep -E '^[a-zA-Z_-]+:.*?## .*$$' \
            | sort \
            | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'
  
    id: ## Output BUILD_ID being used
        @echo $(BUILD_ID)