Allow to register/unregister an array of plugins

The plugins service now accepts an array of plugin instances to register or unregister (for consistency, renamed `Chart.plugins.remove` to `unregister`). Also added a few methods to manipulate registered plugins, such as `count`, `getAll` and `clear` (mainly used by our unit tests).

src/core/core.plugin.js

@@ -7,25 +7,62 @@ module.exports = function(Chart) {
 	/**
 	 * The plugin service singleton
 	 * @namespace Chart.plugins
+	 * @since 2.1.0
 	 */
 	Chart.plugins = {
 		_plugins: [],
 
-		// Register a new plugin
-		register: function(plugin) {
+		/**
+		 * Registers the given plugin(s) if not already registered.
+		 * @param {Array|Object} plugins plugin instance(s).
+		 */
+		register: function(plugins) {
 			var p = this._plugins;
-			if (p.indexOf(plugin) === -1) {
-				p.push(plugin);
-			}
+			([]).concat(plugins).forEach(function(plugin) {
+				if (p.indexOf(plugin) === -1) {
+					p.push(plugin);
+				}
+			});
 		},
 
-		// Remove a registered plugin
-		remove: function(plugin) {
+		/**
+		 * Unregisters the given plugin(s) only if registered.
+		 * @param {Array|Object} plugins plugin instance(s).
+		 */
+		unregister: function(plugins) {
 			var p = this._plugins;
-			var idx = p.indexOf(plugin);
-			if (idx !== -1) {
-				p.splice(idx, 1);
-			}
+			([]).concat(plugins).forEach(function(plugin) {
+				var idx = p.indexOf(plugin);
+				if (idx !== -1) {
+					p.splice(idx, 1);
+				}
+			});
+		},
+
+		/**
+		 * Remove all registered p^lugins.
+		 * @since 2.1.5
+		 */
+		clear: function() {
+			this._plugins = [];
+		},
+
+		/**
+		 * Returns the number of registered plugins?
+		 * @returns {Number}
+		 * @since 2.1.5
+		 */
+		count: function() {
+			return this._plugins.length;
+		},
+
+		/**
+		 * Returns all registered plugin intances.
+		 * @returns {Array} array of plugin objects.
+		 * @since 2.1.5
+		 */
+		getAll: function() {
+			return this._plugins;
 		},
 
 		/**

test/core.plugin.tests.js

@@ -1,44 +1,72 @@
-// Plugin tests
-describe('Test the plugin system', function() {
+describe('Chart.plugins', function() {
 	var oldPlugins;
 
 	beforeAll(function() {
-		oldPlugins = Chart.plugins._plugins;
+		oldPlugins = Chart.plugins.getAll();
 	});
 
 	afterAll(function() {
-		Chart.plugins._plugins = oldPlugins;
+		Chart.plugins.register(oldPlugins);
 	});
 
 	beforeEach(function() {
-		Chart.plugins._plugins = [];
+		Chart.plugins.clear();
 	});
 
-	it ('Should register plugins', function() {
-		var myplugin = {};
-		Chart.plugins.register(myplugin);
-		expect(Chart.plugins._plugins.length).toBe(1);
+	describe('Chart.plugins.register', function() {
+		it('should register a plugin', function() {
+			Chart.plugins.register({});
+			expect(Chart.plugins.count()).toBe(1);
+			Chart.plugins.register({});
+			expect(Chart.plugins.count()).toBe(2);
+		});
 
-		// Should only add plugin once
-		Chart.plugins.register(myplugin);
-		expect(Chart.plugins._plugins.length).toBe(1);
+		it('should register an array of plugins', function() {
+			Chart.plugins.register([{}, {}, {}]);
+			expect(Chart.plugins.count()).toBe(3);
+		});
+
+		it('should succeed to register an already registered plugin', function() {
+			var plugin = {};
+			Chart.plugins.register(plugin);
+			expect(Chart.plugins.count()).toBe(1);
+			Chart.plugins.register(plugin);
+			expect(Chart.plugins.count()).toBe(1);
+			Chart.plugins.register([{}, plugin, plugin]);
+			expect(Chart.plugins.count()).toBe(2);
+		});
 	});
 
-	it ('Should allow unregistering plugins', function() {
-		var myplugin = {};
-		Chart.plugins.register(myplugin);
-		expect(Chart.plugins._plugins.length).toBe(1);
+	describe('Chart.plugins.unregister', function() {
+		it('should unregister a plugin', function() {
+			var plugin = {};
+			Chart.plugins.register(plugin);
+			expect(Chart.plugins.count()).toBe(1);
+			Chart.plugins.unregister(plugin);
+			expect(Chart.plugins.count()).toBe(0);
+		});
 
-		// Should only add plugin once
-		Chart.plugins.remove(myplugin);
-		expect(Chart.plugins._plugins.length).toBe(0);
+		it('should unregister an array of plugins', function() {
+			var plugins = [{}, {}, {}];
+			Chart.plugins.register(plugins);
+			expect(Chart.plugins.count()).toBe(3);
+			Chart.plugins.unregister(plugins.slice(0, 2));
+			expect(Chart.plugins.count()).toBe(1);
+		});
 
-		// Removing a plugin that doesn't exist should not error
-		Chart.plugins.remove(myplugin);
+		it('should succeed to unregister a plugin not registered', function() {
+			var plugin = {};
+			Chart.plugins.register(plugin);
+			expect(Chart.plugins.count()).toBe(1);
+			Chart.plugins.unregister({});
+			expect(Chart.plugins.count()).toBe(1);
+			Chart.plugins.unregister([{}, plugin]);
+			expect(Chart.plugins.count()).toBe(0);
+		});
 	});
 
 	describe('Chart.plugins.notify', function() {
-		it ('should call plugins with arguments', function() {
+		it('should call plugins with arguments', function() {
 			var myplugin = {
 				count: 0,
 				trigger: function(chart) {