function installDependency()

in src/plugman/install.js [485:553]
57 lines of code
13 McCabe index (conditional complexity)

function installDependency (dep, install, options) {
    let opts;
    dep.install_dir = path.join(install.plugins_dir, dep.id);

    events.emit('verbose', 'Requesting plugin "' + (dep.version ? dep.id + '@' + dep.version : dep.id) + '".');

    if (fs.existsSync(dep.install_dir)) {
        const pluginInfo = new PluginInfo(dep.install_dir);
        const version_installed = pluginInfo.version;
        let version_required = dep.version;

        if (dep.version) {
            if (Number(dep.version.replace('.', ''))) {
                version_required = '^' + dep.version;
            }
        }
        // strip -dev from the installed plugin version so it properly passes
        // semver.satisfies
        let stripped_version;
        if (version_installed.includes('-dev')) {
            stripped_version = semver.inc(version_installed, 'patch');
        }
        if (options.force ||
            semver.satisfies(version_installed, version_required, /* loose= */true) ||
            semver.satisfies(stripped_version, version_required, /* loose= */true) ||
            version_required === null ||
            version_required === undefined ||
            version_required === '') {
            events.emit('log', 'Plugin dependency "' + (version_installed ? dep.id + '@' + version_installed : dep.id) + '" already fetched, using that version.');
        } else {
            const msg = 'Version of installed plugin: "' +
                dep.id + '@' + version_installed +
                '" does not satisfy dependency plugin requirement "' +
                dep.id + '@' + version_required +
                 '". Try --force to use installed plugin as dependency.';
            return Promise.resolve()
                .then(function () {
                    // Remove plugin
                    return fs.removeSync(path.join(install.plugins_dir, install.top_plugin_id));
                }).then(function () {
                    // Return promise chain and finally reject
                    return Promise.reject(new CordovaError(msg));
                });
        }
        opts = Object.assign({}, options, {
            cli_variables: install.filtered_variables,
            is_top_level: false
        });
        return module.exports.runInstall(install.actions, install.platform, install.project_dir, dep.install_dir, install.plugins_dir, opts);
    } else {
        events.emit('verbose', 'Plugin dependency "' + dep.id + '" not fetched, retrieving then installing.');

        opts = Object.assign({}, options, {
            cli_variables: install.filtered_variables,
            is_top_level: false,
            subdir: dep.subdir,
            git_ref: dep.git_ref,
            expected_id: dep.id
        });

        const dep_src = dep.url.length ? dep.url : (dep.version ? dep.id + '@' + dep.version : dep.id);
        return possiblyFetch(dep_src, install.plugins_dir, opts)
            .then(
                function (plugin_dir) {
                    return module.exports.runInstall(install.actions, install.platform, install.project_dir, plugin_dir, install.plugins_dir, opts);
                }
            );
    }
}