shfmt(1) General Commands Manual shfmt(1)
NAME
shfmt - Format shell programs
SYNOPSIS
shfmt [flags] [path...]
DESCRIPTION
shfmt formats shell programs. If the only argument is a dash (-) or no
arguments are given, standard input will be used. If a given path is a
directory, all shell scripts found under that directory will be used.
If any EditorConfig files are found, they will be used to apply format-
ting options. If any parser or printer flags are given to the tool, no
EditorConfig files will be used. A default like -i=0 can be used for
this purpose.
shfmt's default shell formatting was chosen to be consistent, common,
and predictable. Some aspects of the format can be configured via
printer flags.
OPTIONS
Generic flags
-version
Show version and exit.
-l
List files whose formatting differs from shfmt's.
-w
Write result to file instead of stdout.
-d
Error with a diff when the formatting differs.
The diff uses color when the output is a terminal. To never use
color, set a non-empty NO_COLOR or TERM=dumb. To always use color,
set a non-empty FORCE_COLOR.
-s
Simplify the code.
-mn
Minify the code to reduce its size (implies -s).
Parser flags
-ln <str>
Language variant to parse (bash/posix/mksh/bats, default bash).
-p
Shorthand for -ln=posix.
-filename str
Provide a name for the standard input file.
Printer flags
-i <uint>
Indent: 0 for tabs (default), >0 for number of spaces.
-bn
Binary ops like && and | may start a line.
-ci
Switch cases will be indented.
-sr
Redirect operators will be followed by a space.
-kp
Keep column alignment paddings.
-fn
Function opening braces are placed on a separate line.
Utility flags
-f
Recursively find all shell files and print the paths.
-tojson
Print syntax tree to stdout as a typed JSON.
EXAMPLES
Format all the scripts under the current directory, printing which are
modified:
shfmt -l -w .
For CI, one can use a variant where formatting changes are just shown
as diffs:
shfmt -d .
The following formatting flags closely resemble Google's shell style
defined in <https://google.github.io/styleguide/shell.xml>:
shfmt -i 2 -ci -bn
Below is a sample EditorConfig file as defined by <https://editorcon-
fig.org/>, showing how to set any option:
[*.sh]
# like -i=4
indent_style = space
indent_size = 4
shell_variant = posix # like -ln=posix
binary_next_line = true # like -bn
switch_case_indent = true # like -ci
space_redirects = true # like -sr
keep_padding = true # like -kp
function_next_line = true # like -fn
# Ignore the entire "third_party" directory.
[third_party/**]
ignore = true
shfmt can also replace bash -n to check shell scripts for syntax er-
rors. It is more exhaustive, as it parses all syntax statically and re-
quires valid UTF-8:
$ echo '${foo:1 2}' | bash -n
$ echo '${foo:1 2}' | shfmt >/dev/null
1:9: not a valid arithmetic operator: 2
$ echo 'foo=(1 2)' | bash --posix -n
$ echo 'foo=(1 2)' | shfmt -p >/dev/null
1:5: arrays are a bash feature
AUTHORS
Maintained by Daniel Martà <mvdan@mvdan.cc>, who is assisted by other
open source contributors. For more information and development, see
<https://github.com/mvdan/sh>.
2022-02-22 shfmt(1)
Generated by dwww version 1.14 on Fri Jan 24 09:20:29 CET 2025.