`class PackageManager`

Detects and invokes npm-compatible package managers without replacing them.

Definitions

`def self.detect(configuration, environment: ENV)`

Detect the package manager selected by a project.

Signature

parameter　configuration　Configuration: The project configuration.
parameter　environment　Hash: Environment variables used for explicit selection.
returns　PackageManager: The selected package-manager wrapper.
raises　ConfigurationError: If selection is ambiguous or unsupported.

Implementation

def self.detect(configuration, environment: ENV)
	if name = environment["NODE_PACKAGE_MANAGER"]
		return new(configuration.root, name)
	end
	
	if declaration = configuration.package_json["packageManager"]
		unless declaration.is_a?(String)
			raise ConfigurationError, "packageManager must be a string!"
		end
		
		return new(configuration.root, declaration.split("@", 2).first)
	end
	
	managers = LOCK_FILES.filter_map do |path, manager|
		manager if (configuration.root + path).file?
	end.uniq
	
	if managers.size > 1
		raise ConfigurationError, "Multiple package manager lock files were found: #{managers.join(', ')}!"
	end
	
	new(configuration.root, managers.first || "npm")
end

`def initialize(root, name)`

Initialize a package-manager wrapper.

Signature

parameter　root　String | Pathname: The directory in which commands will run.
parameter　name　String: The package-manager executable name.
raises　ConfigurationError: If the package manager is unsupported.

Implementation

def initialize(root, name)
	unless SUPPORTED.include?(name)
		raise ConfigurationError, "Unsupported package manager: #{name.inspect}!"
	end
	
	@root = root
	@name = name
end

`attr :root`

Signature

attribute　String | Pathname: The directory in which commands run.

`attr :name`

Signature

attribute　String: The selected package-manager name.

`def install(frozen: false)`

Install the project's dependencies.

Signature

parameter　frozen　Boolean: Whether the lock file must remain unchanged.
raises　Error: If the package-manager command fails.

Implementation

def install(frozen: false)
	execute(install_command(frozen: frozen))
end

`def run(script)`

Run a package script.

Signature

parameter　script　String: The script name from package.json.
raises　ArgumentError: If the script name is empty.
raises　Error: If the package-manager command fails.

Implementation

def run(script)
	unless script.is_a?(String) && !script.empty?
		raise ArgumentError, "Script must be a non-empty string!"
	end
	
	execute([@name, "run", script])
end

`def install_command(frozen: false)`

Construct the installation command for the selected package manager.

Signature

parameter　frozen　Boolean: Whether the lock file must remain unchanged.
returns　Array(String): The command and arguments to execute.

Implementation

def install_command(frozen: false)
	command = case @name
	when "npm"
		frozen ? ["npm", "ci"] : ["npm", "install"]
	when "pnpm"
		["pnpm", "install"]
	when "yarn"
		["yarn", "install"]
	when "bun"
		["bun", "install"]
	end
	
	if frozen && @name != "npm"
		command << (@name == "yarn" ? "--immutable" : "--frozen-lockfile")
	end
	
	command
end