Building using just

Basic justfile configuration

This configuration if called with Just build from any Lua file will execute init.lua in project root (pwd/cwd) directory.

# Runs lua project
build:
    lua init.lua

Filename prompt

If you want to have prompt that's going to ask you for input you need to enable positional arguments with set positional-arguments (only once per file) and write any amount of arguments you like.

set positional-arguments
# Asks for lua file to run
run File:
    lua \$1

Use current file

just.nvim also supports "keywords" (or macros) arguments which will not trigger any prompts, but instead will insert their contents instead.

set positional-arguments
# Runs file in current buffer
run FILEPATH:
    lua \$1

Advanced keyword use

Also keywords can be chained to be able to manipulate them inside of task. It is recommended to add bash (or shell of your choice) shebang (#!/bin/bash) after task name.

set positional-arguments
# Logs current time and date in log file with prompted message
log RELDIR FILENOEXT DATE TIME CWD Message:
    #!/bin/bash
    echo \$1/\$2 \$3 \$4: \$6 >> \$5/logfile.log

Define aliases, requirements and variables

set positional-arguments

CFLAGS = -Wno

# Build both main.c and io.h
build: main_c io_h

buildWithMessage: main_c io_h
    echo 'Printed after main.c and io.h'

buildHeaderFirst: io_h && main_c
    # Will not print "echo 'Printed after io.h but before main.c'" before executing
    @echo 'Printed after io.h but before main.c'

main_c:
    gcc main.c

io_h:
    gcc io.h {{CFLAGS}}

Further reading on how to use justfile can be continued on just github page.

Argument keywords (macros)

Keywords are always fully in upper case and will not trigger any prompts.

List of keywords:

• FILEPATH - full file path including file name and file extension (/path/to/file.extension).
• FILENAME - file name and extension only (file.extension).
• FILEDIR - full path excluding file (/path/to).
• FILEEXT - file extension only (extension).
• FILENOEXT - file name only (file).
• CWD - current working directory (/path/to).
• RELPATH - relative file path including name and extension (subdir/subsubdir/file.ext or file.ext if file is in CWD).
• RELDIR - relative file path excluding file (subdir/subsubdir or . if file in CWD)
• TIME - time in 24 hour format (18:20:30: HH:MM:SS).
• DATE - date in DD/MM/YYYY format (21/12/2022).
• USDATE - date in MM/DD/YYYY format (12/21/2022).
• USERNAME - your user name (VimEnjoyer2006). POSIX (LINUX) ONLY
• PCNAME - your PC name (VimEnjoyer2006PC). POSIX (LINUX) ONLY
• OS - your OS (Linux). POSIX (LINUX) ONLY

Errors

• If you are getting error that contains "__TS__StringSplit" and "find" when trying to use any of build tasks then there's probably an error with your default shell (i.e. fish printing welcome message in non-interactive (not in terminal) mode) which might result in vim.fn.shell outputing rubbish instead of contents of justfile.

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Cheatsheet

Set a variable (variable case is arbitrary)

SINGLE := "--single"

Export variable

export MYHOME := "/new/home"

Join paths:

PATHS := "path/to" / "file" + ".txt"

Conditions

foo := if "2" == "2" { "Good!" } else { "1984" }

String literals

escaped_string := "\\"\\\\" # will eval to "\\
raw_string := '\\"\\\\' # will eval to \\"\\\\
exec_string := \`ls\` # will be set to result of inner command

Hide configuration from just --list, prepend _ or add [private]

[private]
_test: build_d

Alias to a recipe (just noecho)

alias noecho := _echo

Silence commands or recipes by prepending @ (i.e hide "dub build"):

@build_d_custom:
    @dub build

Continue even on fail by adding "-"

test:
   -cat notexists.txt
   echo "Still executes"

Configuration using variable from above (and positional argument $1)

buildFile FILENAME:
    dub build {{SINGLE}} \$1

Set env ([linux] makes recipe be usable only in linux)

[linux]
@test_d:
    #!/bin/bash

A command's arguments can be passed to dependency (also default arguments)

push target="debug": (build target)

Use + (1 ore more) or * (0 or more) to make argument variadic. Must be last

ntest +FILES="justfile1 justfile2":

Run set configurations (recipe requirements)

all: build_d build_d_custom _echo

This example will run in order "a", "b", "c", "d"

b: a && c d

Each recipe line is executed by a new shell (use shebang to prevent)

foo:
    pwd    # This \`pwd\` will print the same directory
    cd bar
    pwd    # as this \`pwd\`!