From 45318ab7289df3e73a46b62ce93adc5f505d2f3f Mon Sep 17 00:00:00 2001
From: Ehsan Akhgari <ehsan@mozilla.com>
Date: Sat, 6 Nov 2010 18:49:26 -0400
Subject: [PATCH] Bug 551704 - Part 3: Don't copy invisible BR nodes to the
 clipboard for editable elements, to make us more compatible with WebKit and
 Opera; r=bzbarsky a=blocking-betaN+

---
 content/base/src/nsHTMLContentSerializer.cpp  | 44 +++++++++++
 editor/idl/nsIHTMLEditor.idl                  |  7 +-
 editor/libeditor/html/nsHTMLEditor.cpp        | 10 +++
 .../libeditor/html/tests/test_bug551704.html  | 77 ++++++++++++++++++-
 4 files changed, 135 insertions(+), 3 deletions(-)

diff --git a/content/base/src/nsHTMLContentSerializer.cpp b/content/base/src/nsHTMLContentSerializer.cpp
index 23a8b68ce346..550ddb9e31cb 100644
--- a/content/base/src/nsHTMLContentSerializer.cpp
+++ b/content/base/src/nsHTMLContentSerializer.cpp
@@ -68,6 +68,10 @@
 #include "nsLWBrkCIID.h"
 #include "nsIScriptElement.h"
 #include "nsAttrName.h"
+#include "nsIDocShell.h"
+#include "nsIEditorDocShell.h"
+#include "nsIEditor.h"
+#include "nsIHTMLEditor.h"
 
 static const PRInt32 kLongLineLen = 128;
 
@@ -81,6 +85,40 @@ nsresult NS_NewHTMLContentSerializer(nsIContentSerializer** aSerializer)
   return CallQueryInterface(it, aSerializer);
 }
 
+static
+PRBool
+IsInvisibleBreak(nsIContent *aNode, nsIAtom *aTag) {
+  // xxxehsan: we should probably figure out a way to determine
+  // if a BR node is visible without using the editor.
+  if (aTag != nsGkAtoms::br || !aNode->IsEditable()) {
+    return PR_FALSE;
+  }
+
+  // Grab the editor associated with the document
+  nsIDocument *doc = aNode->GetCurrentDoc();
+  if (doc) {
+    nsPIDOMWindow *window = doc->GetWindow();
+    if (window) {
+      nsIDocShell *docShell = window->GetDocShell();
+      if (docShell) {
+        nsCOMPtr<nsIEditorDocShell> editorDocShell = do_QueryInterface(docShell);
+        if (editorDocShell) {
+          nsCOMPtr<nsIEditor> editor;
+          editorDocShell->GetEditor(getter_AddRefs(editor));
+          nsCOMPtr<nsIHTMLEditor> htmlEditor = do_QueryInterface(editor);
+          if (htmlEditor) {
+            PRBool isVisible = PR_FALSE;
+            nsCOMPtr<nsIDOMNode> domNode = do_QueryInterface(aNode);
+            htmlEditor->BreakIsVisible(domNode, &isVisible);
+            return !isVisible;
+          }
+        }
+      }
+    }
+  }
+  return PR_FALSE;
+}
+
 nsHTMLContentSerializer::nsHTMLContentSerializer()
 {
     mIsHTMLSerializer = PR_TRUE;
@@ -204,6 +242,12 @@ nsHTMLContentSerializer::AppendElementStart(nsIContent *aElement,
   }
 
   nsIAtom *name = content->Tag();
+
+  if ((mFlags & nsIDocumentEncoder::OutputPreformatted) &&
+      IsInvisibleBreak(content, name)) {
+    return NS_OK;
+  }
+
   PRBool lineBreakBeforeOpen = LineBreakBeforeOpen(content->GetNameSpaceID(), name);
 
   if ((mDoFormat || forceFormat) && !mPreLevel && !mDoRaw) {
diff --git a/editor/idl/nsIHTMLEditor.idl b/editor/idl/nsIHTMLEditor.idl
index 6550065e6379..a9ba99250b2f 100644
--- a/editor/idl/nsIHTMLEditor.idl
+++ b/editor/idl/nsIHTMLEditor.idl
@@ -51,7 +51,7 @@ interface nsIContentFilter;
   NS_ERROR_GENERATE_SUCCESS(NS_ERROR_MODULE_EDITOR, 1)
 
 %}
-[scriptable, uuid(afc36593-5787-4420-93d9-b2c0ccbf0cad)]
+[scriptable, uuid(c964b8b0-e9e8-11df-9492-0800200c9a66)]
 
 interface nsIHTMLEditor : nsISupports
 {
@@ -608,5 +608,10 @@ interface nsIHTMLEditor : nsISupports
    * @return    true if CR in a paragraph creates a new paragraph
    */
   attribute boolean returnInParagraphCreatesNewParagraph;
+
+  /**
+   * Checks whether a BR node is visible to the user.
+   */
+  boolean breakIsVisible(in nsIDOMNode aNode);
 };
 
diff --git a/editor/libeditor/html/nsHTMLEditor.cpp b/editor/libeditor/html/nsHTMLEditor.cpp
index 5dbb92fd17a8..5617dbcb7335 100644
--- a/editor/libeditor/html/nsHTMLEditor.cpp
+++ b/editor/libeditor/html/nsHTMLEditor.cpp
@@ -1342,6 +1342,16 @@ PRBool nsHTMLEditor::IsVisBreak(nsIDOMNode *aNode)
   return PR_TRUE;
 }
 
+NS_IMETHODIMP
+nsHTMLEditor::BreakIsVisible(nsIDOMNode *aNode, PRBool *aIsVisible)
+{
+  NS_ENSURE_ARG_POINTER(aNode && aIsVisible);
+
+  *aIsVisible = IsVisBreak(aNode);
+
+  return NS_OK;
+}
+
 
 NS_IMETHODIMP
 nsHTMLEditor::GetIsDocumentEditable(PRBool *aIsDocumentEditable)
diff --git a/editor/libeditor/html/tests/test_bug551704.html b/editor/libeditor/html/tests/test_bug551704.html
index 5d106f94054d..937fd27230a7 100644
--- a/editor/libeditor/html/tests/test_bug551704.html
+++ b/editor/libeditor/html/tests/test_bug551704.html
@@ -15,17 +15,90 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=551704
 <p id="display"></p>
 <div id="content">
   <div id="preformatted" style="white-space: pre" contenteditable>a&#10;b</div>
+  <div id="test1" contenteditable><br></div>
+  <div id="test2" contenteditable>a<br></div>
+  <div id="test3" contenteditable style="white-space: pre"><br></div>
+  <div id="test4" contenteditable style="white-space: pre">a<br></div>
+  <div id="test5" contenteditable></div>
+  <div id="test6" contenteditable>a</div>
+  <div id="test7" contenteditable style="white-space: pre"></div>
+  <div id="test8" contenteditable style="white-space: pre">a</div>
 </div>
 <pre id="test">
 <script type="application/javascript">
 
+function testLineBreak(div, type, expectedText, expectedHTML, callback)
+{
+  div.focus();
+  getSelection().collapse(div, 0);
+  type();
+  is(div.innerHTML, expectedHTML, "The expected HTML after editing should be correct");
+  SimpleTest.waitForClipboard(expectedText,
+    function() {
+      getSelection().selectAllChildren(div);
+      synthesizeKey("C", {accelKey: true});
+    },
+    function() {
+      var t = document.createElement("textarea");
+      document.body.appendChild(t);
+      t.focus();
+      synthesizeKey("V", {accelKey: true});
+      is(t.value, expectedText, "The expected text should be copied to the clipboard");
+      callback();
+    },
+    function() {
+      SimpleTest.finish();
+    }
+  );
+}
+
+function typeABCDEF() {
+  synthesizeKey("a", {});
+  typeBCDEF_chars();
+}
+
+function typeBCDEF() {
+  synthesizeKey("VK_RIGHT", {});
+  typeBCDEF_chars();
+}
+
+function typeBCDEF_chars() {
+  synthesizeKey("b", {});
+  synthesizeKey("c", {});
+  synthesizeKey("VK_ENTER", {});
+  synthesizeKey("d", {});
+  synthesizeKey("e", {});
+  synthesizeKey("f", {});
+}
+
 /** Test for Bug 551704 **/
 SimpleTest.waitForExplicitFinish();
-addLoadEvent(function() {
+SimpleTest.waitForFocus(function() {
   var preformatted = document.getElementById("preformatted");
   is(preformatted.innerHTML, "a\nb", "No BR node should be injected for preformatted editable fields");
 
-  SimpleTest.finish();
+  var divs = [];
+  for (var i = 0; i < 8; ++i) {
+    divs[i] = document.getElementById("test" + (i+1));
+  }
+  var current = 0;
+  function doNextTest() {
+    if (current == divs.length) {
+      SimpleTest.finish();
+      return;
+    }
+    var div = divs[current++];
+    if (div.textContent == "a") {
+      var type = typeBCDEF;
+    } else {
+      var type = typeABCDEF;
+    }
+    var expectedHTML = "abc<br>def<br>";
+    var expectedText = "abc\ndef";
+    testLineBreak(div, type, expectedText, expectedHTML, doNextTest);
+  }
+
+  doNextTest();
 });
 
 </script>