Support for "latest version" of a vendor/OS combo

.gitignore

@@ -2,6 +2,8 @@
 logs
 *.log
 
+.idea
+
 # Runtime data
 pids
 *.pid

README.md

@@ -111,6 +111,13 @@ $ ./node_modules/.bin/guacamole --id=firefox_38_OS_X_10_9_Desktop
 { browserName: 'firefox', version: '38', platform: 'OS X 10.9' }
 ```
 
+Fetch the latest version of a browser/OS combination with `--id` and `latest`:
+
+```console
+$ ./node_modules/.bin/guacamole --id=firefox_latest_OS_X_10_9_Desktop
+{ browserName: 'firefox', version: '40', platform: 'OS X 10.9' }
+```
+
 Amend screenResolution with `--screenResolution`. If the API supports that screen resolution, you'll get a result:
 ```console
 $ ./bin/guacamole --id=firefox_38_OS_X_10_9_Desktop --screenResolution=1024x768

src/browsers.js

@@ -3,6 +3,7 @@ var _ = require("lodash");
 var request = require("request");
 var syncRequest = require("sync-request");
 var browsers = [];
+var latest = {};
 var fs = require("fs");
 var path = require("path");
 
@@ -66,6 +67,8 @@ var SauceBrowsers = {
     return browsers.filter(fn);
   },
 
+  latest: latest,
+
   // Return a list of browser desiredCapabilities objects if they exist in our browser list.
   //
   // Match by:
@@ -82,10 +85,23 @@ var SauceBrowsers = {
   // with id, family, and a supported resolutions array (i.e. guacamole's raw internal representation)
   //
   get: function (specs, wrapped) {
+
+    if (specs.id && specs.id.indexOf("latest") > -1) {
+      var splitId = specs.id.split("latest");
+      if (splitId.length === 2) {
+        var browserId = splitId[0].replace("_", "");
+        var osId = splitId[1].replace("_", "");
+        if (latest[browserId] && latest[browserId][osId]) {
+          var latestVersion = latest[browserId][osId];
+          var newId = splitId[0] + latestVersion + splitId[1];
+          specs.id = newId;
+        }
+      }
+    }
+
     return browsers.filter(function (browser) {
       // Match specs. Ignore orientation, and special case screenResolution
       var matching = true;
-
       // Match by id (only if id has been specified)
       if (specs.id && browser.id !== specs.id) {
         var matchesTranslated = false;
@@ -296,12 +312,20 @@ var SauceBrowsers = {
             + "_" + cleanPlatformName(hostOSName)
           )
         } else {
+          var osKey = cleanPlatformName(osName) + "_" + cleanPlatformName(deviceName);
           guacamoleId = (
             cleanPlatformName(name)
             + "_" + cleanPlatformName(browser.short_version)
-            + "_" + cleanPlatformName(osName)
-            + "_" + cleanPlatformName(deviceName)
-          )
+            + "_" + osKey
+          );
+
+          if (!latest[browser.api_name]) {
+            latest[browser.api_name] = {};
+          }
+
+          if(!latest[browser.api_name][osKey] || latest[browser.api_name][osKey] < browser.short_version) {
+            latest[browser.api_name][osKey] = parseInt(browser.short_version, 10);
+          }
         }
 
         var result = {

test/normalize.js

@@ -23,8 +23,20 @@ describe("normalizer", function () {
     });
   });
 
-  it("normalizes Chrome43 on Windows correctly", function () {
-    var id = "chrome_43_Windows_2012_R2_Desktop";
+  it("normalizes Chrome42 on Windows correctly", function () {
+    var id = "chrome_42_Windows_2012_R2_Desktop";
+    var result = Browsers.get({ id: id });
+    expect(result).to.have.length(1);
+
+    var chrome43 = result[0];
+    expect(chrome43).to.have.property("browserName", "chrome");
+    expect(chrome43).to.have.property("platform", "Windows 2012 R2");
+    expect(chrome43).to.have.property("version", "42");
+    expect(chrome43).to.have.property("browserName", "chrome");
+  });
+
+  it("normalizes latest Chrome version on Windows correctly", function () {
+    var id = "chrome_latest_Windows_2012_R2_Desktop";
     var result = Browsers.get({ id: id });
     expect(result).to.have.length(1);