Unify warnings for using v5.2 and <v0.12

Additionally add test coverage to ensure message is printed for invalid
versions.

.gitignore

@@ -1,3 +1,4 @@
 node_modules
 coverage
 npm-debug.log
+.DS_Store

README.md

@@ -13,7 +13,7 @@ This module provides Cloud Debug support for Node.js applications. [Google Cloud
 [![Cloud Debugger Intro](http://img.youtube.com/vi/tyHcK_kAOpw/0.jpg)](https://www.youtube.com/watch?v=tyHcK_kAOpw)
 
 ## Prerequisites
-* Your application will need to be using Node.js version 0.12 or greater. Node.js v5+ is recommended.
+* Your application will need to be using Node.js version 0.12 or greater. Node.js v5+ is recommended. (Node.js v5.2.0 is not supported on account of [this bug](https://github.com/nodejs/node/issues/4297))
 * The source of your application is uploaded to a [cloud source repository](https://cloud.google.com/tools/cloud-repositories/docs/). The Debugger UI needs the source to be available in order to set breakpoints.
 
 ## Quick Start (Node.js v4.x+)

index.js

@@ -22,7 +22,6 @@
 var config = require('./config.js');
 var logger = require('@google/cloud-diagnostics-common').logger;
 var Debuglet = require('./lib/debuglet.js');
-var semver = require('semver');
 
 // exports is populated by the agent
 module.exports = {};
@@ -39,11 +38,6 @@ if (process.env.hasOwnProperty('GCLOUD_DEBUG_REPO_APP_PATH')) {
 
 var log = logger.create(config.logLevel, '@google/cloud-debug');
 
-if (semver.satisfies(process.version, '5.2')) {
-  log.error('Debug is not supported on Node v5.2');
-  return;
-}
-
 if (config.enabled) {
   var debuglet = new Debuglet(config, log);
   debuglet.start();

lib/debuglet.js

@@ -18,8 +18,9 @@
 
 var fs = require('fs');
 var path = require('path');
-var EventEmitter = require('events');
+var EventEmitter = require('events').EventEmitter;
 var util = require('util');
+var semver = require('semver');
 
 var v8debugapi = require('./v8debugapi.js');
 var DebugletApi = require('./debugletapi.js');
@@ -30,9 +31,8 @@ var StatusMessage = require('./apiclasses.js').StatusMessage;
 
 var assert = require('assert');
 
-var NODE_VERSION_MESSAGE = 'V8 Debug API not available – make sure you are ' +
-    'running Node.js >=0.12. Cloud Debugger agent will not be able to take ' +
-    'snapshots.';
+var NODE_VERSION_MESSAGE = 'Node.js version not supported. Node.js 5.2.0 and ' +
+  ' versions older than 0.12 are not supported.';
 
 module.exports = Debuglet;
 
@@ -110,11 +110,11 @@ Debuglet.prototype.start = function() {
           return;
         }
 
-        if (!that.v8debug_) {
-          // V8 Debug API is missing. We report an error message about the Node.js
-          // version, but we keep on running. The idea is that the user may miss
-          // the error message on the console. This way we can report the error
-          // when the user tries to set a breakpoint.
+        if (semver.satisfies(process.version, '5.2 || <0.12')) {
+          // Using an unsupported version. We report an error message about the
+          // Node.js version, but we keep on running. The idea is that the user
+          // may miss the error message on the console. This way we can report the
+          // error when the user tries to set a breakpoint.
           that.logger_.error(NODE_VERSION_MESSAGE);
         }
 
@@ -299,18 +299,16 @@ Debuglet.prototype.removeBreakpoint_ = function(breakpoint) {
  */
 Debuglet.prototype.addBreakpoint_ = function(breakpoint, cb) {
   var that = this;
-  var message;
 
-  if (!that.v8debug_) {
-    message = NODE_VERSION_MESSAGE;
+  if (semver.satisfies(process.version, '5.2 || <0.12')) {
+    var message = NODE_VERSION_MESSAGE;
     that.logger_.error(message);
     breakpoint.status = new StatusMessage(StatusMessage.UNSPECIFIED,
       message, true);
     setImmediate(function() { cb(message); });
     return;
   }
 
-
   that.v8debug_.set(breakpoint, function(err) {
     if (err) {
       cb(err);

test/e2e/test-error-message.js

@@ -0,0 +1,74 @@
+/**
+ * Copyright 2016 Google Inc. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+'use strict';
+
+var assert = require('assert');
+var request = require('request');
+var logger = require('@google/cloud-diagnostics-common').logger;
+var config = require('../../config.js');
+var Debuglet = require('../../lib/debuglet.js');
+var semver = require('semver');
+
+var nock = require('nock');
+nock.disableNetConnect();
+
+describe(__filename, function() {
+  it('should re-fetch breakpoints on error', function(done) {
+    assert(semver.satisfies(process.version, '5.2.x'));
+    var debuglet = new Debuglet(
+      config, logger.create(config.logLevel, '@google/cloud-debug'));
+
+    process.env.GCLOUD_PROJECT_NUM=0;
+
+    var API = 'https://clouddebugger.googleapis.com';
+
+    var scope = nock(API)
+      .post('/v2/controller/debuggees/register')
+      .reply(200, {
+        debuggee: {
+          id: 'bar'
+        }
+      })
+      .get('/v2/controller/debuggees/bar/breakpoints')
+      .reply(200, {
+        breakpoints: [{
+          id: 'test',
+          location: { path: 'fixtures/foo.js', line: 2 }
+        }]
+      })
+      .put('/v2/controller/debuggees/bar/breakpoints/test', function(body) {
+        var status = body.breakpoint.status;
+        var partialMessage = 'Node.js version not supported.';
+        return status.isError &&
+          (status.description.format.indexOf(partialMessage) !== -1);
+      })
+      .reply(200);
+
+    debuglet.once('started', function() {
+      debuglet.debugletApi_.request_ = request; // Avoid authing.
+    });
+    debuglet.once('registered', function reg(id) {
+      assert(id === 'bar');
+      setTimeout(function() {
+        debuglet.stop();
+        scope.done();
+        done();
+      }, 200);
+    });
+
+    debuglet.start();
+  });
+});