Use builtin functions.

* Array.prototype.forEach
* Array.prototype.filter
* Array.prototype.find
* Array.prototype.map
* Array.prototype.some
* Array.isArray
* Number.isNaN
* String.prototype.includes

Signed-off-by: Eric Wang <skygragon@gmail.com>

Author: skygragon

lib/chalk.js

@@ -53,7 +53,7 @@ chalk.wrap = function(pre, post) {
 function bgName(s) { return 'bg' + s[0].toUpperCase() + s.substr(1); }
 
 chalk.init = function() {
-  _.each(require('./helper').getCodeDirData('colors'), function(f) {
+  require('./helper').getCodeDirData('colors').forEach(function(f) {
     var o = {};
     _.pairs(f.data).forEach(function(x) {
       var k = x[0];

lib/commands/cache.js

@@ -42,7 +42,7 @@ cmd.handler = function(argv) {
   } else {
     _.sortBy(caches, function(f) {
       var x = parseInt(f.name.split('.')[0], 10);
-      if (_.isNaN(x)) x = 0;
+      if (Number.isNaN(x)) x = 0;
       return x;
     })
     .forEach(function(f) {

lib/commands/list.js

@@ -51,8 +51,8 @@ cmd.handler = function(argv) {
       if (word.endsWith(word.substr(-1).repeat(6))) {
         log.warn('Hmmm...you might need a new keyboard?');
       }
-      problems = _.filter(problems, function(x) {
-        return x.name.toLowerCase().indexOf(word) >= 0;
+      problems = problems.filter(function(x) {
+        return x.name.toLowerCase().includes(word);
       });
     }
 

lib/commands/show.js

@@ -88,7 +88,7 @@ function showProblem(problem, argv) {
   var code;
   var needcode = argv.gen || argv.codeonly;
   if (needcode) {
-    var template = _.find(problem.templates, function(x) {
+    var template = problem.templates.find(function(x) {
       return x.value === argv.lang;
     });
     if (!template) {
@@ -166,14 +166,14 @@ cmd.handler = function(argv) {
 
       // random select one that not AC-ed yet
       var user = session.getUser();
-      problems = _.filter(problems, function(x) {
+      problems = problems.filter(function(x) {
         if (x.state === 'ac') return false;
         if (!user.paid && x.locked) return false;
         return true;
       });
       if (problems.length === 0) return cb('Problem not found!');
 
-      var problem = problems[_.random(problems.length - 1)];
+      var problem = _.sample(problems);
       core.getProblem(problem, function(e, problem) {
         if (e) return log.fail(e);
         showProblem(problem, argv);

lib/commands/stat.js

@@ -109,7 +109,7 @@ function showGraph(problems) {
   log.info('    ' + header);
 
   var graph = [];
-  _.each(problems, function(problem) {
+  problems.forEach(function(problem) {
     graph[problem.id] = ICONS[problem.state] || ICONS.none;
   });
 
@@ -214,7 +214,7 @@ cmd.handler = function(argv) {
     if (e) return log.fail(e);
 
     if (!argv.lock)
-      problems = _.reject(problems, function(x) { return x.locked; });
+      problems = problems.filter(function(x) { return !x.locked; });
 
     log.info();
     if (argv.graph)    showGraph(problems);

lib/commands/submission.js

@@ -1,6 +1,5 @@
 var fs = require('fs');
 
-var _ = require('underscore');
 var sprintf = require('sprintf-js').sprintf;
 
 var h = require('../helper');
@@ -81,14 +80,14 @@ function exportSubmission(problem, argv, cb) {
       return cb('No submissions?');
 
     // get obj list contain required filetype
-    submissions = _.filter(submissions, function(x) {
+    submissions = submissions.filter(function(x) {
       return argv.lang === 'all' || argv.lang === x.lang;
     });
     if (submissions.length === 0)
       return cb('No submissions in required language.');
 
     // if no accepted, use the latest non-accepted one
-    var submission = _.find(submissions, function(x) {
+    var submission = submissions.find(function(x) {
       return x.status_display === 'Accepted';
     }) || submissions[0];
     submission.ac = (submission.status_display === 'Accepted');

lib/commands/submit.js

@@ -28,7 +28,7 @@ function printResult(actual, k) {
   if (!actual.hasOwnProperty(k)) return;
 
   var v = actual[k] || '';
-  var lines = _.isArray(v) ? v : [v];
+  var lines = Array.isArray(v) ? v : [v];
   lines.forEach(function(line) {
     if (k !== 'state') line = k + ': ' + line;
     log.info('  ' + h.prettyText(' ' + line, actual.ok));

lib/commands/test.js

@@ -44,7 +44,7 @@ function printResult(actual, expect, k) {
   var ok = actual.ok;
   if (expect && !_.isEqual(actual[k], expect[k])) ok = false;
 
-  var lines = _.isArray(v) ? v : [v];
+  var lines = Array.isArray(v) ? v : [v];
   lines.forEach(function(line) {
     if (k !== 'state') line = k + ': ' + line;
     log.info('  ' + h.prettyText(' ' + line, ok));

lib/commands/version.js

@@ -70,7 +70,7 @@ cmd.handler = function(argv) {
   printLine('Icons', _.keys(icon.themes));
 
   log.info('\n[Plugins]');
-  _.each(Plugin.plugins, function(p, k) {
+  Plugin.plugins.forEach(function(p, k) {
     printLine(p.name, p.ver);
   });
 };

lib/core.js

@@ -34,8 +34,8 @@ core.filters = {
 };
 
 function hasTag(o, tag) {
-  return _.isArray(o) &&
-    _.some(o, function(x) { return x.indexOf(tag.toLowerCase()) >= 0; });
+  return Array.isArray(o) &&
+    o.some(function(x) { return x.indexOf(tag.toLowerCase()) >= 0; });
 }
 
 function isLevel(x, q) { return x.level[0].toLowerCase() === q.toLowerCase(); }
@@ -65,11 +65,11 @@ core.filterProblems = function(opts, cb) {
     (opts.query || '').split('').forEach(function(q) {
       var f = QUERY_HANDLERS[q];
       if (!f) return;
-      problems = _.filter(problems, function(x) { return f(x, q); });
+      problems = problems.filter(function(x) { return f(x, q); });
     });
 
     (opts.tag || []).forEach(function(t) {
-      problems = _.filter(problems, function(x) {
+      problems = problems.filter(function(x) {
         return x.category === t ||
           hasTag(x.companies, t) ||
           hasTag(x.tags, t);
@@ -88,7 +88,7 @@ core.getProblem = function(keyword, cb) {
     if (e) return cb(e);
 
     keyword = Number(keyword) || keyword;
-    var problem = _.find(problems, function(x) {
+    var problem = problems.find(function(x) {
       return x.id === keyword || x.name === keyword || x.slug === keyword;
     });
     if (!problem) return cb('Problem not found!');