Configuration

Nushell Configuration with config.toml

Nushell uses a configuration system that loads a toml file at launch time. That configuration file is called the Nushell config.toml file. The path to the configuration file can be found by calling config path. It contains the configuration points that nushell will use as default settings. Each setting follows a key value pattern. A value can be a number, a string, or an array. Below is a description of each setting.

An example of the nushell config.toml can be found in our repo here (opens new window).

Root level configuration settings.

These are at the root level, not because they're more important, but because they are not in a toml section.

Name	Purpose	Value Type	Options
complete_from_path	Whether or not to complete names of binaries on PATH	boolean	true or false
ctrlc_exit	Enables/Disables nushell to exit when the key combination of Ctrl+C is hit multiple times.	boolean	true or false
disable_table_indexes	Enables/Disables the index (#) column on tables.	boolean	true or false
filesize_format	Set the file size units format returned from the ls command.	string	b, kb, kib, mb, mib, gb, gib, etc
filesize_metric	Set the file size metric (power of 1000 / power of 1024). true for KB,MB,GB; false for KiB,MiB,GiB	boolean	true of false
nonzero_exit_errors	Enables/Disables the reporting of non-zeros exit errors.	boolean	true or false
pivot_mode	Tells nushell how to pivot single row tables.	string	auto, always, never
plugin_dirs	Tells nushell to look in these folders for optional nushell plugins.	array	quoted string of folders delimited by commas between brackets [ ]
prompt	Instructs nushell to run this command pipeline for every prompt.	string	quote command pipeline or custom command.
rm_always_trash	Enables/Disables nushell to always delete files to the recycle bin/trash can.	boolean	true or false
skip_welcome_message	Enables/Disables the nushell welcome message.	boolean	true or false
startup	Load and run command at startup. These commands can take the form of aliases, custom commands, or external commands.	array	quoted string of commands delimited by commas between brackets [ ]
table_mode	Defines which "theme" that table drawing should use in nushell.	string	basic, compact, compact_double, light, thin, with_love, rounded, reinforced, heavy, none, other

Color Config section

The [color_config] section of the config.toml file enables you to change the color and formatting of datatypes in nushell. This is most apparent in tables like the output of the ls command.

For each of the options in the color_config section, you are able to set the color alone or with one of the following attributes.

color	abbreviation
green	g
red	r
blue	u
black	b
yellow	y
purple	p
cyan	c
white	w

attribute	abbreviation
bold	b
underline	u
italic	i
dimmed	d
reverse	r

Abbreviated Examples:

• gb means green bold
• ru means red underline
• ud means blue dimmed

Verbose Examples:

• green_bold
• red_underline
• blue_dimmed

Name	Purpose	Value Type	Options
[color_config]	This is the section name	string	Outlined above
header_align	Apply an alignment to the header	string	Outlined above
header_color	Apply a color to the header	string	Outlined above
index_color	Apply a style of the Index (#)	string	Outlined above
leading_trailing_space_bg	Apply a style to leading and trailing space	string	Outlined above
primitive_binary	Apply a style to Primitive::Binary	string	Outlined above
primitive_boolean	Apply a style to Primitive::Boolean	string	Outlined above
primitive_columnpath	Apply a style to Primitive::ColumnPath	string	Outlined above
primitive_date	Apply a style to Primitive::Date	string	Outlined above
primitive_decimal	Apply a style to Primitive::Decimal	string	Outlined above
primitive_duration	Apply a style to Primitive::Duration	string	Outlined above
primitive_filesize	Apply a style to Primitive::Filesize	string	Outlined above
primitive_int	Apply a style to Primitive::Int	string	Outlined above
primitive_line	Apply a style to Primitive::Line	string	Outlined above
primitive_path	Apply a style to Primitive::Path	string	Outlined above
primitive_pattern	Apply a style to Primitive::Pattern	string	Outlined above
primitive_range	Apply a style to Primitive::Range	string	Outlined above
primitive_string	Apply a style to Primitive::String	string	Outlined above
separator_color	Apply a style to the table lines	string	Outlined above

Line Editor section

The [line_editor] section of the config.toml controls how our line editor, rustyline behaves. These configuration settings are specific to the rustyline crate we use.

Name	Purpose	Value Type	Options
[line_editor]	This is the section name
auto_add_history	Enable/Disable automatically add each non-blank line to history	boolean	true or false
bell_style	The bell style for the line editor	string	audible, none, visible
color_mode	The color mode for the line editor	string	enabled, forced, disabled
completion_prompt_limit	When listing completion alternatives, only display one screen of possibilities at a time	number
completion_type	Method used to iterate history items	string	circular, list, fuzzy - note fuzzy is not currently supported by nushell
edit_mode	The mode for the line editor	string	vi or emacs
history_duplicates	Rule to apply regarding the adding of duplicates to the history	string	alwaysadd, ignoreconsecutive
history_ignore_space	Enable/Disable the history to ignore space	boolean	true or false
keyseq_timeout_ms	Duration rustyline will wait for a character when reading an ambiguous key sequence	string	duration in milliseconds
max_history_size	The maximum history size	number
tab_stop	The number of characters for indented/outdented commands	number
completion_match_method	Sets case-sensitivity of autocompletion	string	case-insensitive, case-sensitive

Textview section

The [textview] section of the config.toml file is a section with settings for our textviewer which is currently bat (opens new window). So, all these settings apply to the bat configuration built into nushell. It won't use settings you may currently have on your system if you use bat.

Name	Purpose	Value Type	Options
[textview]	This is the section name
colored_output	Enable/Disable whether or not the output should be colorized	boolean	true or false
grid	Enable/Disable a grid	boolean	true or false
header	Enable/Disable a header	boolean	true or false
line_numbers	Enable/Disable line numbers	boolean	true or false
pager	Set the pager to use	string	less, more, etc
paging_mode	Set the paging mode	string	always, quitifonescreen, never
snip	Enable/Disable snip	boolean	true or false
tab_width	The width of tab characters. Currently, a value of 0 will cause tabs to be passed through without expanding them.	number
term_width	The character width of the terminal	string
theme	Set the bat color theme to use	string
true_color	Enable/Disable whether the output terminal supports true color	boolean	true or false
use_italics	Enable/Disable italic type	boolean	true or false
vcs_modification_markers	Enable/Disable version control system modification markers	boolean	true or false
wrapping_mode	Set if and how text should be wrapped	string	character, nowrapping

Path section

The [path] section in the config.toml is used to store folders that are generally where executable programs are located. The path section is an array type field so it requires quoted string directory paths delmited by commas.

You can use this command to initially populate the [path] section of your config.toml file.

config set path $nu.path

To view the [path] section of your config.toml you can type the following.

echo $nu.path

Environment variables section

The [env] section of the config.toml is used to store permanent environment variables that nushell can use.

You can use this command to initially populate the [env] section of your config.toml file.

config set env $nu.env

To view the [env] section of your config.toml you can type the following command.

echo $nu.env

Example config.toml below closely matches the file found in our repo here (opens new window).

filesize_format = "B" # can be b, kb, kib, mb, mib, gb, gib, etc
skip_welcome_message = true
disable_table_indexes = false
nonzero_exit_errors = true
startup = [
    "alias la = ls --long",
    "def nudown [] {fetch https://api.github.com/repos/nushell/nushell/releases | get assets | select name download_count}",
    "def nuver [] {version | pivot key value}",
    ]
table_mode = "other" # basic, compact, compact_double, light, thin, with_love, rounded, reinforced, heavy, none, other
plugin_dirs = ["D:\\Src\\GitHub\\nu-plugin-lib\\samples\\Nu.Plugin.Len\\bin\\Debug\\netcoreapp3.1"]
pivot_mode = "auto" # auto, always, never
ctrlc_exit = false
complete_from_path = true
rm_always_trash = true
prompt = "echo $(ansi gb) $(pwd) $(ansi reset) \"(\" $(ansi cb) $(do -i { git rev-parse --abbrev-ref HEAD | str trim }) $(ansi reset) \")\" $(char newline) $(ansi yb) $(date --format \"%m/%d/%Y %I:%M:%S%.3f %p\" --raw) $(ansi reset) \"> \" | str collect"

[color_config]
primitive_int = "green"
primitive_decimal = "red"
primitive_filesize = "ur"
primitive_string = "pb"
primitive_line = "yellow"
primitive_columnpath = "cyan"
primitive_pattern = "white"
primitive_boolean = "green"
primitive_date = "ru"
primitive_duration = "blue"
primitive_range = "purple"
primitive_path = "yellow"
primitive_binary = "cyan"
separator_color = "purple"
header_align = "l" # left|l, right|r, center|c
header_color = "c" # green|g, red|r, blue|u, black|b, yellow|y, purple|p, cyan|c, white|w
header_bold = true
index_color = "rd"
leading_trailing_space_bg = "white"

[line_editor]
max_history_size = 100000
history_duplicates = "ignoreconsecutive" # alwaysadd,ignoreconsecutive
history_ignore_space = false
completion_type = "circular" # circular, list, fuzzy
completion_prompt_limit = 100
keyseq_timeout_ms = 500 # ms
edit_mode = "emacs" # vi, emacs
auto_add_history = true
bell_style = "audible" # audible, none, visible
color_mode = "enabled" # enabled, forced, disabled
tab_stop = 4

[textview]
term_width = "default" # "default" or a number
tab_width = 4
colored_output = true
true_color = true
header = true
line_numbers = true
grid = false
vcs_modification_markers = true
snip = true
wrapping_mode = "NoWrapping" # Character, NoWrapping
use_italics = true
paging_mode = "QuitIfOneScreen" # Always, QuitIfOneScreen, Never
pager = "less"
theme = "TwoDark"

# These are from a Windows system, Mac and Linux will look slightly different
path = [
    "C:\\WINDOWS\\system32",
    "C:\\WINDOWS",
    "C:\\WINDOWS\\System32\\OpenSSH\\",
]

# Some environment variables removed to protect the innocent
# These are from a Windows environment, Mac and Linux will look slightly different
[env]
ALLUSERSPROFILE = "C:\\ProgramData"
CommonProgramFiles = "C:\\Program Files\\Common Files"
"CommonProgramFiles(x86)" = "C:\\Program Files (x86)\\Common Files"
CommonProgramW6432 = "C:\\Program Files\\Common Files"
ComSpec = "C:\\WINDOWS\\system32\\cmd.exe"
DriverData = "C:\\Windows\\System32\\Drivers\\DriverData"
HOMEDRIVE = "C:"
NUMBER_OF_PROCESSORS = "16"
NVIDIAWHITELISTED = "0x01"
OS = "Windows_NT"
PATHEXT = ".COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC"
POWERSHELL_DISTRIBUTION_CHANNEL = "MSI:Windows 10 Pro"
PROCESSOR_ARCHITECTURE = "AMD64"
PROCESSOR_IDENTIFIER = "Intel64 Family 6 Model 158 Stepping 13, GenuineIntel"
PROCESSOR_LEVEL = "6"
PROCESSOR_REVISION = "9e0d"
ProgramData = "C:\\ProgramData"
ProgramFiles = "C:\\Program Files"
"ProgramFiles(x86)" = "C:\\Program Files (x86)"
ProgramW6432 = "C:\\Program Files"
PSModulePath = "C:\\Program Files\\WindowsPowerShell\\Modules;C:\\WINDOWS\\system32\\WindowsPowerShell\\v1.0\\Modules"
PUBLIC = "C:\\Users\\Public"
SHIM_MCCOMPAT = "0x810000001"
SystemDrive = "C:"
SystemRoot = "C:\\WINDOWS"
windir = "C:\\WINDOWS"
WSLENV = "WT_SESSION::WT_PROFILE_ID"

Startup commands

To run commands at start, Nushell offers a special part of the configuration that contains a list of strings which will be treated as commands you haved typed in as Nushell starts up.

Let's add a single line to print "hello" as Nushell starts up:

config set startup ["echo 'hello'"]

The startup section lets you do the configuration steps that should happen before your Nushell session begins, including adding aliases or custom commands.

Using the config command

Setting variables

To set one of these variables, you can use config set. For example:

> config set line_editor.edit_mode "vi"

Setting a variable from the pipeline

There's an additional way to set a variable, and that is to use the contents of the pipeline as the value you want to use for the variable. For this, use the set_into flag:

> echo "bar" | config set_into foo

This is helpful when working with the env and path variables.

Listing all variables

Running the config command without any arguments will show a table of the current configuration settings:

> config
─────────────────┬──────────────────
 completion_type │ circular
 env             │ [row 51 columns]
 path            │ [table 9 rows]
 startup         │ [table 1 rows]
─────────────────┴──────────────────

Note: if you haven't set any configuration variables, yet, this may be empty.

Getting a variable

Using the get flag, you can retrieve the value for a given variable:

> config get line_editor.edit_mode

Removing a variable

To remove a variable from the configuration, use the remove flag:

> config remove line_editor.edit_mode

Clearing the whole configuration

If you want to clear the whole configuration and start fresh, you can use the clear flag. Of course, be careful with this as once you run it, the configuration file is also cleared.

> config clear

Finding where the configuration is stored

The configuration file is loaded from a default location. To find what this location is on your system, you can ask for it using the path flag:

> config path
/home/jonathant/.config/nu/config.toml

Configuring Nu as a login shell

To use Nu as a login shell, you'll need to configure the path and env configuration variables. With these, you'll have enough support to run external commands as a login shell.

Before switching, run Nu inside of another shell, like Bash. Then, take the environment and PATH from that shell with the following commands:

> config set path $nu.path
> config set env  $nu.env

The $nu.path and $nu.env values are set to the current PATH and environment variables, respectively. More information about these two config sections is available in the config.toml description. Once you set these into the configuration, they'll be available later when using Nu as a login shell.

Next, on some distros you'll also need to ensure Nu is in the /etc/shells list:

> cat /etc/shells
# /etc/shells: valid login shells
/bin/sh
/bin/dash
/bin/bash
/bin/rbash
/usr/bin/screen
/usr/bin/fish
/home/jonathan/.cargo/bin/nu

With this, you should be able to chsh and set Nu to be your login shell. After a logout, on your next login you should be greeted with a shiny Nu prompt.

macOS: Keeping /usr/bin/open as open

Some tools (e.g. Emacs) rely on an open command to open files on Mac. As nushell has its own open command which has different semantics and shadows /usr/bin/open, these tools will error out when trying to use it. One way to work around this is to define aliases in your startup config like this:

cat (config path)

startup = [
  "alias nuopen = open",
  "alias open = ^open",
]

Or using a one-liner:

config set startup (config get startup | append "alias nuopen = open" | append "alias open = ^open")

Prompt configuration

Prompt configuration is handled by setting the value of prompt.

For example, to use Starship (opens new window), download it and enter the following command (0.18.2 and later):

config set prompt "starship prompt"

Now restart Nu.

nushell on 📙 master [$] is 📦 v0.18.2 via 🦀 v1.48.0-nightly
❯

If your prompt looks a bit garbled like this:

%{%}~%{%}
%{%}❯%{%}

you may want to unset the STARSHIP_SHELL environment variable when setting the prompt.

config set prompt "STARSHIP_SHELL= starship prompt"