This runs an arbitrary command from a package's "scripts" object. If no
"command" is provided, it will list the available scripts. run[-script] is
used by the test, start, restart, and stop commands, but can be called
directly, as well. When the scripts in the package are printed out, they're
separated into lifecycle (test, start, restart) and directly-run scripts.
As of email@example.com, you can
use custom arguments when executing scripts. The special option -- is used by
getopt to delimit the end of the options. npm will pass
all the arguments after the -- directly to your script:
npm run test -- --grep="pattern"
The arguments will only be passed to the script specified after npm run
and not to any pre or post script.
The env script is a special built-in command that can be used to list
environment variables that will be available to the script at runtime. If an
"env" command is defined in your package, it will take precedence over the
In addition to the shell's pre-existing PATH, npm run adds
node_modules/.bin to the PATH provided to scripts. Any binaries provided by
locally-installed dependencies can be used without the node_modules/.bin
prefix. For example, if there is a devDependency on tap in your package,
you should write:
The actual shell your script is run within is platform dependent. By default,
on Unix-like systems it is the /bin/sh command, on Windows it is the cmd.exe.
The actual shell referred to by /bin/sh also depends on the system.
As of firstname.lastname@example.org you can
customize the shell with the script-shell configuration.
Scripts are run from the root of the module, regardless of what your current
working directory is when you call npm run. If you want your script to
use different behavior based on what subdirectory you're in, you can use the
INIT_CWD environment variable, which holds the full path you were in when
you ran npm run.
npm run sets the NODE environment variable to the node executable with
which npm is executed. Also, if the --scripts-prepend-node-path is passed,
the directory within which node resides is added to the
PATH. If --scripts-prepend-node-path=auto is passed (which has been the
default in npm v3), this is only performed when that node executable is
not found in the PATH.
If you try to run a script without having a node_modules directory and it fails,
you will be given a warning to run npm install, just in case you've forgotten.
You can use the --silent flag to prevent showing npm ERR! output on error.
You can use the --if-present flag to avoid exiting with a non-zero exit code
when the script is undefined. This lets you run potentially undefined scripts
without breaking the execution chain.