Bug 751744 - Add a Revert to Saved menu item to the scratchpad; r=harth

browser/devtools/scratchpad/scratchpad.js

@@ -35,6 +35,7 @@ const PREF_RECENT_FILES_MAX = "devtools.scratchpad.recentFilesMax";
 const BUTTON_POSITION_SAVE = 0;
 const BUTTON_POSITION_CANCEL = 1;
 const BUTTON_POSITION_DONT_SAVE = 2;
+const BUTTON_POSITION_REVERT=0;
 
 let keysbundle = Services.strings.createBundle("chrome://global-platform/locale/platformKeys.properties");
 
@@ -922,6 +923,72 @@ var Scratchpad = {
     }
   },
 
+  /**
+   * Restore content from saved version of current file.
+   *
+   * @param function aCallback
+   *        Optional function you want to call when file is saved
+   */
+  revertFile: function SP_revertFile(aCallback)
+  {
+    
+    let file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);
+    file.initWithPath(this.filename);
+
+    if (!file.exists()) {
+      return;
+    }
+
+    this.importFromFile(file, false, function(aStatus, aContent) {
+      if (aCallback) {
+        aCallback(aStatus);
+      }
+    });
+  },
+
+  /**
+   * Prompt to revert scratchpad if it has unsaved changes.
+   *
+   * @param function aCallback
+   *        Optional function you want to call when file is saved. The callback
+   *        receives three arguments:
+   *          - aRevert (boolean) - tells if the file has been reverted.
+   *          - status (number) - the file revert status result (if the file was
+   *          saved).
+   */
+  promptRevert: function SP_promptRervert(aCallback)
+  {
+    if (this.filename) {
+      let ps = Services.prompt;
+      let flags = ps.BUTTON_POS_0 * ps.BUTTON_TITLE_REVERT +
+                  ps.BUTTON_POS_1 * ps.BUTTON_TITLE_CANCEL;
+
+      let button = ps.confirmEx(window,
+                          this.strings.GetStringFromName("confirmRevert.title"),
+                          this.strings.GetStringFromName("confirmRevert"),
+                          flags, null, null, null, null, {});
+      if (button == BUTTON_POSITION_CANCEL) {
+        if (aCallback) {
+          aCallback(false);
+        }
+
+        return;
+      }
+      if (button == BUTTON_POSITION_REVERT) {
+        this.revertFile(function(aStatus) {
+          if(aCallback){
+            aCallback(true, aStatus);
+          }
+        });
+
+        return;
+      }
+    }
+    if (aCallback) {
+      aCallback(false);
+    }
+  },
+
   /**
    * Open the Error Console.
    */
@@ -1107,6 +1174,14 @@ var Scratchpad = {
   _onDirtyChanged: function SP__onDirtyChanged(aEvent)
   {
     Scratchpad._updateTitle();
+    if (Scratchpad.filename) {
+      if (Scratchpad.editor.dirty) {
+        document.getElementById("sp-cmd-revert").removeAttribute("disabled");
+      }
+      else {
+        document.getElementById("sp-cmd-revert").setAttribute("disabled", true);
+      }
+    }
   },
 
   /**

browser/devtools/scratchpad/scratchpad.xul

@@ -33,6 +33,7 @@
   <command id="sp-cmd-clearRecentFiles" oncommand="Scratchpad.clearRecentFiles();"/>
   <command id="sp-cmd-save" oncommand="Scratchpad.saveFile();"/>
   <command id="sp-cmd-saveas" oncommand="Scratchpad.saveFileAs();"/>
+  <command id="sp-cmd-revert" oncommand="Scratchpad.promptRevert();" disabled="true"/>
 
   <!-- TODO: bug 650340 - implement printFile()
   <command id="sp-cmd-printFile" oncommand="Scratchpad.printFile();" disabled="true"/>
@@ -132,6 +133,10 @@
                 label="&saveFileAsCmd.label;"
                 accesskey="&saveFileAsCmd.accesskey;"
                 command="sp-cmd-saveas"/>
+      <menuitem id="sp-menu-revert"
+                label="&revertCmd.label;"
+                accesskey="&revertCmd.accesskey;"
+                command="sp-cmd-revert"/>
       <menuseparator/>
 
       <!-- TODO: bug 650340 - implement printFile

browser/devtools/scratchpad/test/Makefile.in

@@ -33,6 +33,7 @@ MOCHITEST_BROWSER_FILES = \
 		browser_scratchpad_bug_650760_help_key.js \
 		browser_scratchpad_bug_651942_recent_files.js \
 		browser_scratchpad_bug756681_display_non_error_exceptions.js \
+		browser_scratchpad_bug_751744_revert_to_saved.js \
 		head.js \
 
 include $(topsrcdir)/config/rules.mk

browser/devtools/scratchpad/test/browser_scratchpad_bug_751744_revert_to_saved.js

@@ -0,0 +1,137 @@
+/* vim: set ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+let tempScope = {};
+Cu.import("resource://gre/modules/NetUtil.jsm", tempScope);
+Cu.import("resource://gre/modules/FileUtils.jsm", tempScope);
+let NetUtil = tempScope.NetUtil;
+let FileUtils = tempScope.FileUtils;
+
+// Reference to the Scratchpad object.
+let gScratchpad;
+
+// Reference to the temporary nsIFiles.
+let gFile;
+
+// Temporary file name.
+let gFileName = "testFileForBug751744.tmp"
+
+
+// Content for the temporary file.
+let gFileContent = "/* this file is already saved */\n" +
+                   "function foo() { alert('bar') }";
+let gLength = gFileContent.length;
+
+// Reference to the menu entry.
+let menu;
+
+function startTest()
+{
+  gScratchpad = gScratchpadWindow.Scratchpad;
+  menu = gScratchpadWindow.document.getElementById("sp-menu-revert");
+  createAndLoadTemporaryFile();
+}
+
+function testAfterSaved() {
+  // Check if the revert menu is disabled as the file is at saved state.
+  ok(menu.hasAttribute("disabled"), "The revert menu entry is disabled.");
+
+  // chancging the text in the file
+  gScratchpad.setText("\nfoo();", gLength, gLength);
+  // Checking the text got changed
+  is(gScratchpad.getText(), gFileContent + "\nfoo();",
+     "The text changed the first time.");
+
+  // Revert menu now should be enabled.
+  ok(!menu.hasAttribute("disabled"),
+     "The revert menu entry is enabled after changing text first time");
+
+  // reverting back to last saved state.
+  gScratchpad.revertFile(testAfterRevert);
+}
+
+function testAfterRevert() {
+  // Check if the file's text got reverted
+  is(gScratchpad.getText(), gFileContent,
+     "The text reverted back to original text.");
+  // The revert menu should be disabled again.
+  ok(menu.hasAttribute("disabled"),
+     "The revert menu entry is disabled after reverting.");
+
+  // chancging the text in the file again
+  gScratchpad.setText("\nalert(foo.toSource());", gLength, gLength);
+  // Saving the file.
+  gScratchpad.saveFile(testAfterSecondSave);
+}
+
+function testAfterSecondSave() {
+  // revert menu entry should be disabled.
+  ok(menu.hasAttribute("disabled"),
+     "The revert menu entry is disabled after saving.");
+
+  // changing the text.
+  gScratchpad.setText("\nfoo();", gLength + 23, gLength + 23);
+
+  // revert menu entry should get enabled yet again.
+  ok(!menu.hasAttribute("disabled"),
+     "The revert menu entry is enabled after changing text third time");
+
+  // reverting back to last saved state.
+  gScratchpad.revertFile(testAfterSecondRevert);
+}
+
+function testAfterSecondRevert() {
+  // Check if the file's text got reverted
+  is(gScratchpad.getText(), gFileContent + "\nalert(foo.toSource());",
+     "The text reverted back to the changed saved text.");
+  // The revert menu should be disabled again.
+  ok(menu.hasAttribute("disabled"),
+     "Revert menu entry is disabled after reverting to changed saved state.");
+  gFile.remove(false);
+  gFile = null;
+  gScratchpad = null;
+}
+
+function createAndLoadTemporaryFile()
+{
+  // Create a temporary file.
+  gFile = FileUtils.getFile("TmpD", [gFileName]);
+  gFile.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, 0666);
+
+  // Write the temporary file.
+  let fout = Cc["@mozilla.org/network/file-output-stream;1"].
+             createInstance(Ci.nsIFileOutputStream);
+  fout.init(gFile.QueryInterface(Ci.nsILocalFile), 0x02 | 0x08 | 0x20,
+            0644, fout.DEFER_OPEN);
+
+  let converter = Cc["@mozilla.org/intl/scriptableunicodeconverter"].
+                  createInstance(Ci.nsIScriptableUnicodeConverter);
+  converter.charset = "UTF-8";
+  let fileContentStream = converter.convertToInputStream(gFileContent);
+
+  NetUtil.asyncCopy(fileContentStream, fout, tempFileSaved);
+}
+
+function tempFileSaved(aStatus)
+{
+  ok(Components.isSuccessCode(aStatus),
+     "the temporary file was saved successfully");
+
+  // Import the file into Scratchpad.
+  gScratchpad.setFilename(gFile.path);
+  gScratchpad.importFromFile(gFile.QueryInterface(Ci.nsILocalFile),  true,
+                             testAfterSaved);
+}
+
+function test()
+{
+  gBrowser.selectedTab = gBrowser.addTab();
+  gBrowser.selectedBrowser.addEventListener("load", function onLoad() {
+    gBrowser.selectedBrowser.removeEventListener("load", onLoad, true);
+    openScratchpad(startTest);
+  }, true);
+
+  content.location = "data:text/html,<p>test reverting to last saved state of" +
+                     " a file </p>";
+}

browser/locales/en-US/chrome/browser/devtools/scratchpad.dtd

@@ -36,6 +36,9 @@
 <!ENTITY openRecentMenu.label         "Open Recent">
 <!ENTITY openRecentMenu.accesskey     "R">
 
+<!ENTITY revertCmd.label              "Revert…">
+<!ENTITY revertCmd.accesskey          "t">
+
 <!ENTITY saveFileCmd.label            "Save">
 <!ENTITY saveFileCmd.accesskey        "S">
 <!ENTITY saveFileCmd.commandkey       "s">

browser/locales/en-US/chrome/browser/devtools/scratchpad.properties

@@ -54,6 +54,14 @@ confirmClose=Do you want to save the changes you made to this scratchpad?
 # you try to close a scratchpad with unsaved changes.
 confirmClose.title=Unsaved Changes
 
+# LOCALIZATION NOTE  (confirmRevert): This is message in the prompt dialog when
+# you try to revert unsaved content of scratchpad.
+confirmRevert=Do you want to revert the changes you made to this scratchpad?
+
+# LOCALIZATION NOTE  (confirmRevert.title): This is title of the prompt dialog when
+# you try to revert unsaved content of scratchpad.
+confirmRevert.title=Revert Changes
+
 # LOCALIZATION NOTE  (scratchpadIntro): This is a multi-line comment explaining
 # how to use the Scratchpad. Note that this should be a valid JavaScript
 # comment inside /* and */.