setup.py 文件源码

def run(self):
        has_npm = self.has_npm()
        if not has_npm:
            log.error("`npm` unavailable.  If you're running this command using sudo, make sure `npm` is available to sudo")

        env = os.environ.copy()
        env['PATH'] = npm_path

        if self.should_run_npm_install():
            log.info("Installing build dependencies with npm.  This may take a while...")
            check_call(['npm', 'install'], cwd=node_root, stdout=sys.stdout, stderr=sys.stderr)
            os.utime(self.node_modules, None)

        for t in self.targets:
            if not os.path.exists(t):
                msg = 'Missing file: %s' % t
                if not has_npm:
                    msg += '\nnpm is required to build a development version of widgetsnbextension'
                raise ValueError(msg)

        # update package data in case this created new files
        update_package_data(self.distribution)