CLI
Use the prettier
command to run Prettier from the command line.
prettier [options] [file/dir/glob ...]
To run your locally installed version of Prettier, prefix the command with
npx
oryarn
(if you use Yarn), i.e.npx prettier --help
, oryarn prettier --help
.
To format a file in-place, use --write
. (Note: This overwrites your files!)
In practice, this may look something like:
prettier . --write
This command formats all files supported by Prettier in the current directory and its subdirectories.
It’s recommended to always make sure that prettier --write .
only formats what you want in your project. Use a .prettierignore
file to ignore things that should not be formatted.
A more complicated example:
prettier docs package.json "{app,__{tests,mocks}__}/**/*.js" --write --single-quote --trailing-comma all
Don’t forget the quotes around the globs! The quotes make sure that Prettier CLI expands the globs rather than your shell, which is important for cross-platform usage.
It’s better to use a configuration file for formatting options like
--single-quote
and--trailing-comma
instead of passing them as CLI flags. This way the Prettier CLI, editor integrations, and other tooling can all know what options you use.
File patterns
Given a list of paths/patterns, the Prettier CLI first treats every entry in it as a literal path.
If the path points to an existing file, Prettier CLI proceeds with that file and doesn’t resolve the path as a glob pattern.
If the path points to an existing directory, Prettier CLI recursively finds supported files in that directory. This resolution process is based on file extensions and well-known file names that Prettier and its plugins associate with supported languages.
Otherwise, the entry is resolved as a glob pattern using the glob syntax from the
fast-glob
module.
Prettier CLI will ignore files located in node_modules
directory. To opt out from this behavior, use --with-node-modules
flag.
To escape special characters in globs, one of the two escaping syntaxes can be used: prettier "\[my-dir]/*.js"
or prettier "[[]my-dir]/*.js"
. Both match all JS files in a directory named [my-dir]
, however the latter syntax is preferable as the former doesn’t work on Windows, where backslashes are treated as path separators.
--check
When you want to check if your files are formatted, you can run Prettier with the --check
flag (or -c
).
This will output a human-friendly message and a list of unformatted files, if any.
prettier . --check
Console output if all files are formatted:
Checking formatting...
All matched files use Prettier code style!
Console output if some of the files require re-formatting:
Checking formatting...
[warn] src/fileA.js
[warn] src/fileB.js
[warn] Code style issues found in 2 files. Forgot to run Prettier?
The command will return exit code 1
in the second case, which is helpful inside the CI pipelines.
Human-friendly status messages help project contributors react on possible problems.
To minimise the number of times prettier --check
finds unformatted files, you may be interested in configuring a pre-commit hook in your repo.
Applying this practice will minimise the number of times the CI fails because of code formatting problems.
If you need to pipe the list of unformatted files to another command, you can use --list-different
flag instead of --check
.
Exit codes
Code | Information |
---|---|
0 | Everything formatted properly |
1 | Something wasn’t formatted properly |
2 | Something’s wrong with Prettier |
--debug-check
If you're worried that Prettier will change the correctness of your code, add --debug-check
to the command. This will cause Prettier to print an error message if it detects that code correctness might have changed. Note that --write
cannot be used with --debug-check
.
--find-config-path
and --config
If you are repeatedly formatting individual files with prettier
, you will incur a small performance cost when Prettier attempts to look up a configuration file. In order to skip this, you may ask Prettier to find the config file once, and re-use it later on.
$ prettier --find-config-path path/to/file.js
path/to/.prettierrc
This will provide you with a path to the configuration file, which you can pass to --config
:
prettier path/to/file.js --write --config path/to/.prettierrc
You can also use --config
if your configuration file lives somewhere where Prettier cannot find it, such as a config/
directory.
If you don’t have a configuration file, or want to ignore it if it does exist, you can pass --no-config
instead.
--ignore-path
Path to a file containing patterns that describe files to ignore. By default, Prettier looks for ./.prettierignore
.
--list-different
Another useful flag is --list-different
(or -l
) which prints the filenames of files that are different from Prettier formatting. If there are differences the script errors out, which is useful in a CI scenario.
prettier . --single-quote --list-different
You can also use --check
flag, which works the same way as --list-different
, but also prints a human-friendly summary message to stdout.
--no-config
Do not look for a configuration file. The default settings will be used.
--config-precedence
Defines how config file should be evaluated in combination of CLI options.
cli-override (default)
CLI options take precedence over config file
file-override
Config file take precedence over CLI options
prefer-file
If a config file is found will evaluate it and ignore other CLI options. If no config file is found, CLI options will evaluate as normal.
This option adds support to editor integrations where users define their default configuration but want to respect project specific configuration.
--no-editorconfig
Don’t take .editorconfig
into account when parsing configuration. See the prettier.resolveConfig
docs for details.
--with-node-modules
Prettier CLI will ignore files located in node_modules
directory. To opt out from this behavior, use --with-node-modules
flag.
--write
This rewrites all processed files in place. This is comparable to the eslint --fix
workflow. You can also use -w
alias.
--log-level
Change the level of logging for the CLI. Valid options are:
error
warn
log
(default)debug
silent
--stdin-filepath
A path to the file that the Prettier CLI will treat like stdin. For example:
abc.css
.name {
display: none;
}
shell
$ cat abc.css | prettier --stdin-filepath abc.css
.name {
display: none;
}
--ignore-unknown
With --ignore-unknown
(or -u
), prettier will ignore unknown files matched by patterns.
prettier "**/*" --write --ignore-unknown
--no-error-on-unmatched-pattern
Prevent errors when pattern is unmatched.
--no-plugin-search
Disable plugin autoloading.
--cache
If this option is enabled, the following values are used as cache keys and the file is formatted only if one of them is changed.
- Prettier version
- Options
- Node.js version
- (if
--cache-strategy
ismetadata
) file metadata, such as timestamps - (if
--cache-strategy
iscontent
) content of the file
prettier . --write --cache
Running Prettier without --cache
will delete the cache.
Also, since the cache file is stored in ./node_modules/.cache/prettier/.prettier-cache
, so you can use rm ./node_modules/.cache/prettier/.prettier-cache
to remove it manually.
Plugins version and implementation are not used as cache keys. We recommend that you delete the cache when updating plugins.
--cache-location
Path to the cache file location used by --cache
flag. If you don't explicit --cache-location
, Prettier saves cache file at ./node_modules/.cache/prettier/.prettier-cache
.
If a file path is passed, that file is used as the cache file.
prettier . --write --cache --cache-location=path/to/cache-file
--cache-strategy
Strategy for the cache to use for detecting changed files. Can be either metadata
or content
.
In general, metadata
is faster. However, content
is useful for updating the timestamp without changing the file content. This can happen, for example, during git operations such as git clone
, because it does not track file modification times.
If no strategy is specified, content
will be used.
prettier . --write --cache --cache-strategy metadata