From 82ef3d31a281985219919b20cfb4fccb84da98e0 Mon Sep 17 00:00:00 2001
From: Andrew Stewart <andrew@stwrt.ca>
Date: Thu, 19 Mar 2015 17:33:31 -0700
Subject: [PATCH] Add exploding interface functions for Driver/Adaptor

Explicit is better than implicit, and this causes errors to be more
specific
---
 lib/adaptor.js           | 28 ++++++++++++++++++++++++++++
 lib/driver.js            | 28 ++++++++++++++++++++++++++++
 spec/lib/adaptor.spec.js | 31 ++++++++++++++++++++++++++++++-
 spec/lib/driver.spec.js  | 31 ++++++++++++++++++++++++++++++-
 4 files changed, 116 insertions(+), 2 deletions(-)

diff --git a/lib/adaptor.js b/lib/adaptor.js
index bb393f4..2e2d03e 100644
--- a/lib/adaptor.js
+++ b/lib/adaptor.js
@@ -12,6 +12,10 @@ var Basestar = require("./basestar"),
     Utils = require("./utils"),
     _ = require("./utils/helpers");
 
+function formatErrorMessage(name, message) {
+  return ["Error in connection", "'" + name + "'", "- " + message].join(" ");
+}
+
 // Public: Creates a new Adaptor
 //
 // opts - hash of acceptable params
@@ -43,6 +47,30 @@ var Adaptor = module.exports = function Adaptor(opts) {
 
 Utils.subclass(Adaptor, Basestar);
 
+// Public: Basic #connect function. Must be overwritten by a descendent class
+//
+// Returns nothing, throws an error
+Adaptor.prototype.connect = function() {
+  var message = formatErrorMessage(
+    this.name,
+    "Adaptor#connect method must be overwritten by descendant classes."
+  );
+
+  throw new Error(message);
+};
+
+// Public: Basic #disconnect function. Must be overwritten by a descendent class
+//
+// Returns nothing, throws an error
+Adaptor.prototype.disconnect = function() {
+  var message = formatErrorMessage(
+    this.name,
+    "Adaptor#disconnect method must be overwritten by descendant classes."
+  );
+
+  throw new Error(message);
+};
+
 // Public: Expresses the Connection in JSON format
 //
 // Returns an Object containing Connection data
diff --git a/lib/driver.js b/lib/driver.js
index a574bfd..7b34109 100644
--- a/lib/driver.js
+++ b/lib/driver.js
@@ -12,6 +12,10 @@ var Basestar = require("./basestar"),
     Utils = require("./utils"),
     _ = require("./utils/helpers");
 
+function formatErrorMessage(name, message) {
+  return ["Error in driver", "'" + name + "'", "- " + message].join(" ");
+}
+
 // Public: Creates a new Driver
 //
 // opts - hash of acceptable params
@@ -47,6 +51,30 @@ var Driver = module.exports = function Driver(opts) {
 
 Utils.subclass(Driver, Basestar);
 
+// Public: Basic #start function. Must be overwritten by a descendent class
+//
+// Returns nothing, throws an error
+Driver.prototype.start = function() {
+  var message = formatErrorMessage(
+    this.name,
+    "Driver#start method must be overwritten by descendant classes."
+  );
+
+  throw new Error(message);
+};
+
+// Public: Basic #halt function. Must be overwritten by a descendent class
+//
+// Returns nothing, throws an error
+Driver.prototype.halt = function() {
+  var message = formatErrorMessage(
+    this.name,
+    "Driver#halt method must be overwritten by descendant classes."
+  );
+
+  throw new Error(message);
+};
+
 Driver.prototype.setupCommands = function(commands, proxy) {
   if (proxy == null) {
     proxy = this.connection;
diff --git a/spec/lib/adaptor.spec.js b/spec/lib/adaptor.spec.js
index 3498f7c..28fa930 100644
--- a/spec/lib/adaptor.spec.js
+++ b/spec/lib/adaptor.spec.js
@@ -1,7 +1,8 @@
 /* jshint expr:true */
 "use strict";
 
-var Adaptor = source("adaptor");
+var Adaptor = source("adaptor"),
+    Utils = source("utils");
 
 describe("Adaptor", function() {
   var adaptor;
@@ -15,4 +16,32 @@ describe("Adaptor", function() {
       expect(adaptor.name).to.be.eql("adaptor");
     });
   });
+
+  describe("#interface methods", function() {
+    var child;
+
+    var Child = function Child() {};
+
+    Utils.subclass(Child, Adaptor);
+
+    beforeEach(function() {
+      child = new Child();
+    });
+
+    describe("#connect", function() {
+      it("throws an error unless overwritten", function() {
+        expect(child.connect).to.throw();
+        child.connect = function() {};
+        expect(child.connect).to.not.throw();
+      });
+    });
+
+    describe("#disconnect", function() {
+      it("throws an error unless overwritten", function() {
+        expect(child.disconnect).to.throw();
+        child.disconnect = function() {};
+        expect(child.disconnect).to.not.throw();
+      });
+    });
+  });
 });
diff --git a/spec/lib/driver.spec.js b/spec/lib/driver.spec.js
index 207b5a4..391b069 100644
--- a/spec/lib/driver.spec.js
+++ b/spec/lib/driver.spec.js
@@ -1,7 +1,8 @@
 /* jshint expr:true */
 "use strict";
 
-var Driver = source("driver");
+var Driver = source("driver"),
+    Utils = source("utils");
 
 describe("Driver", function() {
   var connection, driver;
@@ -47,6 +48,34 @@ describe("Driver", function() {
     });
   });
 
+  describe("#interface methods", function() {
+    var child;
+
+    var Child = function Child() {};
+
+    Utils.subclass(Child, Driver);
+
+    beforeEach(function() {
+      child = new Child();
+    });
+
+    describe("#start", function() {
+      it("throws an error unless overwritten", function() {
+        expect(child.start).to.throw();
+        child.start = function() {};
+        expect(child.start).to.not.throw();
+      });
+    });
+
+    describe("#halt", function() {
+      it("throws an error unless overwritten", function() {
+        expect(child.halt).to.throw();
+        child.halt = function() {};
+        expect(child.halt).to.not.throw();
+      });
+    });
+  });
+
   describe("#toJSON", function() {
     var driver, json;