lib/plugins/resolveVersion.js
function resolveVersion(plugin) {
    var npmId = Plugin.nameToNpmID(plugin.getName());
    var requiredVersion = plugin.getVersion();

    if (plugin.isGitDependency()) {
        return Promise.resolve(requiredVersion);
    }

    return initNPM()
    .then(function() {
        return Promise.nfcall(npm.commands.view, [npmId + '@' + requiredVersion, 'engines'], true);
    })
    .then(function(versions) {
        versions = Immutable.Map(versions).entrySeq();

        var result = versions
            .map(function(entry) {
                return {
                    version: entry[0],
                    gitbook: (entry[1].engines || {}).gitbook
                };
            })
            .filter(function(v) {
                return v.gitbook && gitbook.satisfies(v.gitbook);
            })
            .sort(function(v1, v2) {
                return semver.lt(v1.version, v2.version)? 1 : -1;
            })
            .get(0);

        if (!result) {
            return undefined;
        } else {
            return result.version;
        }
    });
}
function resolveVersion(plugin) {
    var npmId = Plugin.nameToNpmID(plugin.getName());
    var requiredVersion = plugin.getVersion();

    if (plugin.isGitDependency()) {
        return Promise.resolve(requiredVersion);
    }

    return initNPM()
    .then(function() {
        return Promise.nfcall(npm.commands.view, [npmId + '@' + requiredVersion, 'engines'], true);
    })
    .then(function(versions) {
        versions = Immutable.Map(versions).entrySeq();

        var result = versions
            .map(function(entry) {
                return {
                    version: entry[0],
                    gitbook: (entry[1].engines || {}).gitbook
                };
            })
            .filter(function(v) {
                return v.gitbook && gitbook.satisfies(v.gitbook);
            })
            .sort(function(v1, v2) {
                return semver.lt(v1.version, v2.version)? 1 : -1;
            })
            .get(0);

        if (!result) {
            return undefined;
        } else {
            return result.version;
        }
    });
}
function resolveVersion ( plugin ) { var npmId = Plugin . nameToNpmID ( plugin . getName ( ) ) ; var requiredVersion = plugin . getVersion ( ) ; if ( plugin . isGitDependency ( ) ) { return Promise . resolve ( requiredVersion ) ; } return initNPM ( ) . then ( function ( ) { return Promise . nfcall ( npm . commands . view , [ npmId + '@' + requiredVersion , 'engines' ] , true ) ; } ) . then ( function ( versions ) { versions = Immutable . Map ( versions ) . entrySeq ( ) ; var result = versions . map ( function ( entry ) { return { version : entry [ 0 ] , gitbook : ( entry [ 1 ] . engines || { } ) . gitbook } ; } ) . filter ( function ( v ) { return v . gitbook && gitbook . satisfies ( v . gitbook ) ; } ) . sort ( function ( v1 , v2 ) { return semver . lt ( v1 . version , v2 . version ) ? 1 : - 1 ; } ) . get ( 0 ) ; if ( ! result ) { return undefined ; } else { return result . version ; } } ) ; }
Resolve a plugin dependency to a version

@param {PluginDependency} plugin
@return {Promise<String>}
Resolve a plugin dependency to a version