diff -r 000000000000 -r 6474c204b198 browser/devtools/commandline/test/browser_cmd_screenshot.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/commandline/test/browser_cmd_screenshot.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,183 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that screenshot command works properly
+const TEST_URI = "http://example.com/browser/browser/devtools/commandline/" +
+                 "test/browser_cmd_screenshot.html";
+
+let FileUtils = (Cu.import("resource://gre/modules/FileUtils.jsm", {})).FileUtils;
+
+function test() {
+  return Task.spawn(spawnTest).then(finish, helpers.handleError);
+}
+
+function spawnTest() {
+  waitForExplicitFinish();
+
+  info("RUN TEST: non-private window");
+  let normWin = yield addWindow({ private: false });
+  yield addTabWithToolbarRunTests(normWin);
+  normWin.close();
+
+  info("RUN TEST: private window");
+  let pbWin = yield addWindow({ private: true });
+  yield addTabWithToolbarRunTests(pbWin);
+  pbWin.close();
+}
+
+function addTabWithToolbarRunTests(win) {
+  let options = yield helpers.openTab(TEST_URI, { chromeWindow: win });
+  yield helpers.openToolbar(options);
+
+  // Test input status
+  yield helpers.audit(options, [
+    {
+      setup: 'screenshot',
+      check: {
+        input:  'screenshot',
+        markup: 'VVVVVVVVVV',
+        status: 'VALID',
+        args: {
+        }
+      },
+    },
+    {
+      setup: 'screenshot abc.png',
+      check: {
+        input:  'screenshot abc.png',
+        markup: 'VVVVVVVVVVVVVVVVVV',
+        status: 'VALID',
+        args: {
+          filename: { value: "abc.png"},
+        }
+      },
+    },
+    {
+      setup: 'screenshot --fullpage',
+      check: {
+        input:  'screenshot --fullpage',
+        markup: 'VVVVVVVVVVVVVVVVVVVVV',
+        status: 'VALID',
+        args: {
+          fullpage: { value: true},
+        }
+      },
+    },
+    {
+      setup: 'screenshot abc --delay 5',
+      check: {
+        input:  'screenshot abc --delay 5',
+        markup: 'VVVVVVVVVVVVVVVVVVVVVVVV',
+        status: 'VALID',
+        args: {
+          filename: { value: "abc"},
+          delay: { value: 5 },
+        }
+      },
+    },
+    {
+      setup: 'screenshot --selector img#testImage',
+      check: {
+        input:  'screenshot --selector img#testImage',
+        markup: 'VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV',
+        status: 'VALID',
+        args: {
+          selector: {
+            value: options.window.document.getElementById("testImage")
+          },
+        }
+      },
+    },
+  ]);
+
+  // Test capture to file
+  let file = FileUtils.getFile("TmpD", [ "TestScreenshotFile.png" ]);
+
+  yield helpers.audit(options, [
+    {
+      setup: 'screenshot ' + file.path,
+      check: {
+        args: {
+          filename: { value: "" + file.path },
+          fullpage: { value: false },
+          clipboard: { value: false },
+          chrome: { value: false },
+        },
+      },
+      exec: {
+        output: new RegExp("^Saved to "),
+      },
+      post: function() {
+        // Bug 849168: screenshot command tests fail in try but not locally
+        // ok(file.exists(), "Screenshot file exists");
+
+        if (file.exists()) {
+          file.remove(false);
+        }
+      }
+    },
+  ]);
+
+  // Test capture to clipboard
+  let clipid = Ci.nsIClipboard;
+  let clip = Cc["@mozilla.org/widget/clipboard;1"].getService(clipid);
+  let trans = Cc["@mozilla.org/widget/transferable;1"]
+                .createInstance(Ci.nsITransferable);
+  trans.init(null);
+  trans.addDataFlavor("image/png");
+
+  yield helpers.audit(options, [
+    {
+      setup: 'screenshot --fullpage --clipboard',
+      check: {
+        args: {
+          fullpage: { value: true },
+          clipboard: { value: true },
+          chrome: { value: false },
+        },
+      },
+      exec: {
+        output: new RegExp("^Copied to clipboard.$"),
+      },
+      post: function() {
+        try {
+          clip.getData(trans, clipid.kGlobalClipboard);
+          let str = new Object();
+          let strLength = new Object();
+          trans.getTransferData("image/png", str, strLength);
+
+          ok(str.value, "screenshot exists");
+          ok(strLength.value > 0, "screenshot has length");
+        }
+        finally {
+          Services.prefs.setBoolPref("browser.privatebrowsing.keep_current_session", true);
+
+          // Recent PB changes to the test I'm modifying removed the 'pb'
+          // variable, but left this line in tact. This seems so obviously
+          // wrong that I'm leaving this in in case the analysis is wrong
+          // pb.privateBrowsingEnabled = true;
+        }
+      }
+    },
+  ]);
+
+  yield helpers.closeToolbar(options);
+  yield helpers.closeTab(options);
+}
+
+function addWindow(windowOptions) {
+  let deferred = promise.defer();
+
+  let win = OpenBrowserWindow(windowOptions);
+
+  // This feels hacky, we should refactor it
+  whenDelayedStartupFinished(win, function() {
+    // Would like to get rid of this executeSoon, but without it the url
+    // (TEST_URI) provided in addTabWithToolbarRunTests hasn't loaded
+    executeSoon(function() {
+      deferred.resolve(win);
+    });
+  });
+
+  return deferred.promise;
+}