support a JS config file (#1351)

Thanks to @BrandonOCasey for implementing this feature.

cli.js

@@ -54,6 +54,7 @@ cli.loadConfig = function() {
     var _ = require('underscore');
     var args = require('jsdoc/opts/args');
     var Config = require('jsdoc/config');
+    var config;
     var fs = require('jsdoc/fs');
     var path = require('jsdoc/path');
 
@@ -88,8 +89,19 @@ cli.loadConfig = function() {
     }
 
     try {
-        env.conf = new Config( stripJsonComments(fs.readFileSync(confPath, 'utf8')) )
-            .get();
+        switch ( path.extname(confPath) ) {
+            case '.js':
+                config = require(confPath) || {};
+                break;
+            case '.json':
+            case '.EXAMPLE':
+                config = fs.readFileSync(confPath, 'utf8');
+                break;
+            default:
+                cli.exit(1, 'Cannot use config file ' + confPath + '. Only .js and .json files ' +
+                    'are supported.\n' + FATAL_ERROR_MESSAGE);
+        }
+        env.conf = new Config(config).get();
     }
     catch (e) {
         cli.exit(1, 'Cannot parse the config file ' + confPath + ': ' + e + '\n' +

lib/jsdoc/config.js

@@ -10,6 +10,7 @@
 'use strict';
 
 var stripBom = require('jsdoc/util/stripbom');
+var stripJsonComments = require('strip-json-comments');
 
 function mergeRecurse(target, source) {
     Object.keys(source).forEach(function(p) {
@@ -47,11 +48,23 @@ var defaults = {
 /**
     @class
     @classdesc Represents a JSDoc application configuration.
-    @param {string} [json] - The contents of config.json.
+    @param {(string|object)} [jsonOrObject] - The contents of config.json, or a JavaScript object
+    exported from a .js config file.
  */
-function Config(json) {
-    json = JSON.parse( (stripBom.strip(json) || '{}') );
-    this._config = mergeRecurse(defaults, json);
+function Config(jsonOrObject) {
+    if (typeof jsonOrObject === 'undefined') {
+        jsonOrObject = {};
+    }
+
+    if (typeof jsonOrObject === 'string') {
+        jsonOrObject = JSON.parse( (stripJsonComments(stripBom.strip(jsonOrObject)) || '{}') );
+    }
+
+    if (typeof jsonOrObject !== 'object') {
+        jsonOrObject = {};
+    }
+
+    this._config = mergeRecurse(defaults, jsonOrObject);
 }
 
 module.exports = Config;

test/specs/jsdoc/config.js

@@ -34,6 +34,13 @@ describe('jsdoc/config', function() {
             expect( Array.isArray(config.plugins) ).toBe(true);
             expect(config.plugins.length).toBe(0);
         });
+
+        it('should be possible to construct a Config with an empty JavaScript object', function() {
+            var config = new Config({}).get();
+
+            expect( Array.isArray(config.plugins) ).toBe(true);
+            expect(config.plugins.length).toBe(0);
+        });
     });
 
     describe('constructor with leading BOM', function() {
@@ -46,6 +53,16 @@ describe('jsdoc/config', function() {
         });
     });
 
+    describe('constructor with comments', function() {
+        it('should be possible to construct a Config with JSON that includes comments', function() {
+            function getConfig() {
+                return new Config('{\n// comment\n}').get();
+            }
+
+            expect(getConfig).not.toThrow();
+        });
+    });
+
     describe('constructor with plugins value', function() {
         it('should be possible to construct a Config with JSON of an object literal that has a plugin value', function() {
             var config = new Config('{"plugins":[42]}').get();
@@ -54,6 +71,14 @@ describe('jsdoc/config', function() {
             expect(config.plugins.length).toBe(1);
             expect(config.plugins[0]).toBe(42);
         });
+
+        it('should be possible to construct a Config with a JavaScript object that has a plugin value', function() {
+            var config = new Config({'plugins': [42]}).get();
+
+            expect( Array.isArray(config.plugins) ).toBe(true);
+            expect(config.plugins.length).toBe(1);
+            expect(config.plugins[0]).toBe(42);
+        });
     });
 
     describe('constructor with source value', function() {
@@ -62,5 +87,11 @@ describe('jsdoc/config', function() {
 
             expect(config.source.includePattern).toBe('hello');
         });
+
+        it('should be possible to construct a Config with a JavaScript object that has a source value', function() {
+            var config = new Config({'source': {'includePattern': 'hello'}}).get();
+
+            expect(config.source.includePattern).toBe('hello');
+        });
     });
 });

test/specs/jsdoc/opts/args.js

@@ -39,20 +39,34 @@ describe('jsdoc/opts/args', function() {
             expect(r.template).toBe('mytemplate');
         });
 
-        it('should accept a "-c" option and return an object with a "configure" property', function() {
+        it('should accept a "-c" option with a JSON file and return an object with a "configure" property', function() {
             args.parse(['-c', 'myconf.json']);
             var r = args.get();
 
             expect(r.configure).toBe('myconf.json');
         });
 
-        it('should accept a "--configure" option and return an object with a "configure" property', function() {
+        it('should accept a "-c" option with a JS file and return an object with a "configure" property', function() {
+            args.parse(['-c', 'myconf.js']);
+            var r = args.get();
+
+            expect(r.configure).toBe('myconf.js');
+        });
+
+        it('should accept a "--configure" option with a JSON file and return an object with a "configure" property', function() {
             args.parse(['--configure', 'myconf.json']);
             var r = args.get();
 
             expect(r.configure).toBe('myconf.json');
         });
 
+        it('should accept a "--configure" option with a JS file and return an object with a "configure" property', function() {
+            args.parse(['--configure', 'myconf.js']);
+            var r = args.get();
+
+            expect(r.configure).toBe('myconf.js');
+        });
+
         it('should accept an "-e" option and return an object with a "encoding" property', function() {
             args.parse(['-e', 'ascii']);
             var r = args.get();