NPM-EXPLAIN(1) - Explain installed packages

Synopsis

npm explain <folder | specifier>
alias: why

Description

This command will print the chain of dependencies causing a given package to be installed in the current project.

Positional arguments can be either folders within node_modules, or name@version-range specifiers, which will select the dependency relationships to explain.

For example, running npm explain glob within npm's source tree will show:

glob@7.1.6
node_modules/glob
  glob@"^7.1.4" from the root project
glob@7.1.1 dev
node_modules/tacks/node_modules/glob
  glob@"^7.0.5" from rimraf@2.6.2
  node_modules/tacks/node_modules/rimraf
    rimraf@"^2.6.2" from tacks@1.3.0
    node_modules/tacks
      dev tacks@"^1.3.0" from the root project

To explain just the package residing at a specific folder, pass that as the argument to the command. This can be useful when trying to figure out exactly why a given dependency is being duplicated to satisfy conflicting version requirements within the project.

$ npm explain node_modules/nyc/node_modules/find-up
find-up@3.0.0 dev
node_modules/nyc/node_modules/find-up
  find-up@"^3.0.0" from nyc@14.1.1
  node_modules/nyc
    nyc@"^14.1.1" from tap@14.10.8
    node_modules/tap
      dev tap@"^14.10.8" from the root project

Configuration

json

Default: false
Type: Boolean

Whether or not to output JSON data, rather than the normal output.

•: In npm pkg set it enables parsing set values with JSON.parse() before saving them to your package.json.

Not supported by all npm commands.

workspace

Default:
Type: String (can be set multiple times)

Enable running a command in the context of the configured workspaces of the current project while filtering by running only the workspaces defined by this configuration option.

Valid values for the workspace config are either:

Workspace names
Path to a workspace directory
Path to a parent workspace directory (will result in selecting all workspaces within that folder)

When set for the npm init command, this may be set to the folder of a workspace which does not yet exist, to create the folder and set it up as a brand new workspace within the project.

This value is not exported to the environment for child processes.

NAME

Synopsis

Description

Configuration

json

workspace

See Also