Cleanup

lib/package-managers/npm.js

@@ -2,8 +2,8 @@
 const _ = require('lodash');
 const cint = require('cint');
 const semver = require('semver');
-const versionUtil  = require('../version-util.js');
-const spawn        = require('spawn-please');
+const versionUtil = require('../version-util.js');
+const spawn = require('spawn-please');
 const pacote = require('pacote');
 
 const TIME_FIELDS = ['modified', 'created'];
@@ -45,19 +45,19 @@ function parseJson(result, data) {
 }
 
 /**
+ * Returns the value of one of the properties retrieved by npm view.
  * @param {string} packageName   Name of the package
  * @param {string} field         Field such as "versions" or "dist-tags.latest" are parsed from the pacote result (https://www.npmjs.com/package/pacote#packument)
  * @param {string} currentVersion
  * @returns {Promise}            Promised result
  */
 function viewOne(packageName, field, currentVersion) {
     return viewMany(packageName, [field], currentVersion)
-        .then(result => {
-            return result && result[field];
-        });
+        .then(result => result && result[field]);
 }
 
 /**
+ * Returns an object of specified values retrieved by npm view.
  * @param {string} packageName   Name of the package
  * @param {string[]} fields      Array of fields like versions, time, version
  * @param {string} currentVersion
@@ -70,20 +70,16 @@ function viewMany(packageName, fields, currentVersion) {
 
     npmConfig['full-metadata'] = _.includes(fields, 'time');
 
-    return pacote.packument(packageName, npmConfig).then(result => {
-        const resultObject = {};
-        _.each(fields, (field) => {
-            if (field.startsWith('dist-tags.')) {
-                const [tagName, version] = field.split('.');
-                if (result[tagName]) {
-                    resultObject[field] = result.versions[result[tagName][version]];
-                }
-            } else {
-                resultObject[field] = result[field];
+    return pacote.packument(packageName, npmConfig).then(result =>
+        fields.reduce((accum, field) => Object.assign(
+            accum,
+            {
+                [field]: field.startsWith('dist-tags.') ?
+                    result.versions[_.get(result, field)] :
+                    result[field]
             }
-        });
-        return resultObject;
-    });
+        ), {})
+    );
 }
 
 /**
@@ -92,9 +88,7 @@ function viewMany(packageName, fields, currentVersion) {
  * @returns {Array}         An array of versions with the release versions filtered out
  */
 function filterOutPrereleaseVersions(versions, pre) {
-    return _.filter(versions, (version) => {
-        return pre || _.negate(isPre)(version);
-    });
+    return _.filter(versions, version => pre || !isPre(version));
 }
 
 /**
@@ -118,7 +112,7 @@ function doesSatisfyEnginesNode(versions, enginesNode) {
     if (!minVersion) {
         return _.keys(versions);
     }
-    return _.keys(versions).filter((version) => {
+    return _.keys(versions).filter(version => {
         let versionEnginesNode = _.get(versions[version], 'engines.node');
         return versionEnginesNode && semver.satisfies(minVersion, versionEnginesNode);
     });
@@ -203,13 +197,10 @@ module.exports = {
     latest(packageName, currentVersion, options) {
         return viewOne(packageName, 'dist-tags.latest', currentVersion)
             .then(latest => {
-                // if latest exists and latest not satisfies min version of engines.node, set null to it
-                if (latest && !doesSatisfyEnginesNode({[latest.version]: latest}, options.enginesNode).length) {
-                    latest = null;
-                }
                 // if latest exists and latest is not a prerelease version, return it
                 // if latest exists and latest is a prerelease version and --pre is specified, return it
-                if (latest && (!isPre(latest.version) || options.pre)) {
+                // if latest exists and latest not satisfies min version of engines.node
+                if (latest && (!isPre(latest.version) || options.pre) && doesSatisfyEnginesNode({[latest.version]: latest}, options.enginesNode).length) {
                     return latest.version;
                 // if latest is a prerelease version and --pre is not specified, find the next
                 // version that is not a prerelease
@@ -231,19 +222,16 @@ module.exports = {
      */
     newest(packageName, currentVersion, options) {
         return viewMany(packageName, ['time', 'versions'], currentVersion)
-            .then((result) => {
+            .then(result => {
                 const versions = doesSatisfyEnginesNode(result.versions, options.enginesNode);
-                _.keys(result.time).forEach((key) => {
-                    if (!_.includes(TIME_FIELDS, key) && !_.includes(versions, key)) {
-                        delete result.time[key];
-                    }
-                });
-                return _.keys(result.time);
+                return Object.keys(result.time).reduce((accum, key) =>
+                    accum.concat(_.includes(TIME_FIELDS, key) || _.includes(versions, key) ? key : []), []
+                );
             })
             .then(_.partialRight(_.pullAll, TIME_FIELDS))
-            .then(versions => {
-                return _.last(filterOutPrereleaseVersions(versions, options.pre));
-            });
+            .then(versions =>
+                _.last(filterOutPrereleaseVersions(versions, options.pre))
+            );
     },
 
     /**
@@ -254,10 +242,12 @@ module.exports = {
      */
     greatest(packageName, currentVersion, options) {
         return viewOne(packageName, 'versions', currentVersion)
-            .then(versions => {
-                versions = doesSatisfyEnginesNode(versions, options.enginesNode);
-                return _.last(filterOutPrereleaseVersions(versions, options.pre));
-            });
+            .then(versions =>
+                _.last(filterOutPrereleaseVersions(
+                    doesSatisfyEnginesNode(versions, options.enginesNode),
+                    options.pre
+                ))
+            );
     },
 
     /**
@@ -268,11 +258,16 @@ module.exports = {
      */
     greatestMajor(packageName, currentVersion, options) {
         return viewOne(packageName, 'versions', currentVersion)
-            .then(versions => {
-                versions = doesSatisfyEnginesNode(versions, options.enginesNode);
-                versions = filterOutPrereleaseVersions(versions, options.pre);
-                return versionUtil.findGreatestByLevel(versions, currentVersion, 'major');
-            });
+            .then(versions =>
+                versionUtil.findGreatestByLevel(
+                    filterOutPrereleaseVersions(
+                        doesSatisfyEnginesNode(versions, options.enginesNode),
+                        options.pre
+                    ),
+                    currentVersion,
+                    'major'
+                )
+            );
     },
 
     /**
@@ -283,11 +278,16 @@ module.exports = {
      */
     greatestMinor(packageName, currentVersion, options) {
         return viewOne(packageName, 'versions', currentVersion)
-            .then(versions => {
-                versions = doesSatisfyEnginesNode(versions, options.enginesNode);
-                versions = filterOutPrereleaseVersions(versions, options.pre);
-                return versionUtil.findGreatestByLevel(versions, currentVersion, 'minor');
-            });
+            .then(versions =>
+                versionUtil.findGreatestByLevel(
+                    filterOutPrereleaseVersions(
+                        doesSatisfyEnginesNode(versions, options.enginesNode),
+                        options.pre
+                    ),
+                    currentVersion,
+                    'minor'
+                )
+            );
     },
 
     defaultPrefix