Logger should subscribe to updates, not be told what to do

lib/cylon.js

@@ -120,18 +120,7 @@ Cylon.start = function start() {
 //
 // Returns the current config
 Cylon.config = function(opts) {
-  var loggingChanged = (
-    opts.logging && Config.logging !== _.extend(Config.logging, opts.logging)
-  );
-
-  if (_.isObject(opts)) {
-    Config = _.extend(Config, opts);
-  }
-
-  if (loggingChanged) {
-    Logger.setup();
-  }
-
+  if (_.isObject(opts)) { Config.update(opts); }
   return Config;
 };
 

lib/logger.js

@@ -9,9 +9,7 @@ var BasicLogger = require("./logger/basic_logger"),
 
 var Logger = module.exports = {
   setup: function(opts) {
-    if (_.isObject(opts)) {
-      Config.logging = _.extend(Config.logging, opts);
-    }
+    if (_.isObject(opts)) { _.extend(Config.logging, opts); }
 
     var logger = Config.logging.logger,
         level = Config.logging.level || "info";
@@ -23,18 +21,19 @@ var Logger = module.exports = {
 
     logger = (logger == null) ? BasicLogger : logger;
 
-    this.logger = logger || NullLogger;
-    this.level = level;
+    Logger.logger = logger || NullLogger;
+    Logger.level = level;
 
-    return this;
+    return Logger;
   },
 
   toString: function() {
-    return this.logger.toString();
+    return Logger.logger.toString();
   }
 };
 
 Logger.setup();
+Config.subscribe(Logger.setup);
 
 levels.forEach(function(level) {
   Logger[level] = function() {

spec/lib/cylon.spec.js

@@ -111,15 +111,8 @@ describe("Cylon", function() {
 
   describe("#config", function() {
     beforeEach(function() {
-      for (var c in Config) {
-        delete Config[c];
-      }
-
-      stub(Logger, "setup");
-    });
-
-    afterEach(function() {
-      Logger.setup.restore();
+      delete Config.a;
+      delete Config.b;
     });
 
     it("sets config variables", function() {
@@ -146,14 +139,6 @@ describe("Cylon", function() {
       Cylon.config("hello world");
       expect(Config).to.be.eql(config);
     });
-
-    it("updates the Logger setup if that changed", function() {
-      Cylon.config({ a: 1 });
-      expect(Logger.setup).to.not.be.called;
-
-      Cylon.config({ a: 1, logging: { logger: false } });
-      expect(Logger.setup).to.be.called;
-    });
   });
 
   describe("#halt", function() {

spec/lib/logger.spec.js

@@ -1,7 +1,8 @@
 "use strict";
 
 var Logger = lib("logger"),
-    Config = lib("config");
+    Config = lib("config"),
+    NullLogger = lib("logger/null_logger");
 
 describe("Logger", function() {
   afterEach(function() {
@@ -146,4 +147,11 @@ describe("Logger", function() {
       expect(logger.info).to.be.calledWith("info message");
     });
   });
+
+  it("automatically updates if configuration changed", function() {
+    var custom = spy();
+    expect(Logger.logger).to.be.eql(NullLogger);
+    Config.update({ logging: { logger: custom } });
+    expect(Logger.logger).to.be.eql(custom);
+  });
 });