More advanced Text pattern that will take quotes into account.

A more advanced pattern that tries to take quotes into account. In case
this pattern does not work, this commit can be reverted and instead a
simpler pattern is used that relies on html tags being opened and closed
with < and > brackets. It assumes that < and > are always part of HTML
tags so any textual (content) occurrence should be replaced with html
entities (escaping).

src/net/java/sip/communicator/impl/gui/main/chat/ChatConversationPanel.java

@@ -106,10 +106,39 @@ public class ChatConversationPanel
      * correctly escaped, such that there is no occurrence of the symbols <
      * and &gt;.</i>
      *
-     * <p>The first group matches any piece of text outside of HTML tags.</p>
+     * <pre>
+     * In essence this regexp pattern works as follows:
+     * 1. Find all the text that isn't the start of a tag. (so all chars != '<')
+     *    -> This is your actual result: textual content that is not part of a
+     *    tag.
+     * 2. Then, if you find a '<', find as much chars as you can until you find
+     *    '>' (if it is possible at all to find a closing '>')
+     *
+     *    In depth explanation of 2.:
+     *    The text between tags consists mainly of 2 parts:
+     *
+     *    A) a piece of text
+     *    B) some value "between quotes"
+     *
+     *    So everything up to the "quote" is part of a piece of text (A). Then
+     *    if we encounter a "quote" we consider the rest of the text part of the
+     *    value (B) until the value section is closed with a closing "quote".
+     *    (We tend to be rather greedy, so we even swallow '>' along the way
+     *    looking for the closing "quote".)
+     *
+     *    This subpattern is allowed any number of times, until eventually the
+     *    closing '>' is encountered. (Or not if the pattern is incomplete.)
+     *
+     * 3. And consider that 2. is optional, since it could also be that we only
+     *    find plain text, which would all be captured by 1.
+     * </pre>
+     *
+     * <p>The first group matches any piece of text outside of the &lt; and &gt;
+     * brackets that define the start and end of HTML tags.</p>
      */
-    public static final Pattern TEXT_TO_REPLACE_PATTERN = Pattern.compile(
-        "([^<]*+)(?:<[^>]*+>)?", Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
+    static final Pattern TEXT_TO_REPLACE_PATTERN = Pattern.compile(
+        "([^<]*+)(?:<(?:[^>\"]*(?:\"[^\"]*+\"?)*)*+>?)?",
+        Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
 
     /**
      * List for observing text messages.
@@ -206,8 +235,8 @@ public class ChatConversationPanel
         = new ShowPreviewDialog(ChatConversationPanel.this);
 
     /**
-     * The implementation of the routine which scrolls {@link #chatTextPane} to its
-     * bottom.
+     * The implementation of the routine which scrolls {@link #chatTextPane} to
+     * its bottom.
      */
     private final Runnable scrollToBottomRunnable = new Runnable()
     {

test/net/java/sip/communicator/impl/gui/main/chat/ChatConversationPanelTest.java

@@ -0,0 +1,111 @@
+/*
+ * Jitsi, the OpenSource Java VoIP and Instant Messaging client.
+ *
+ * Distributable under LGPL license.
+ * See terms of license at gnu.org.
+ */
+package net.java.sip.communicator.impl.gui.main.chat;
+
+import java.util.*;
+import java.util.Map.Entry;
+import java.util.regex.*;
+
+import junit.framework.*;
+
+/**
+ * Tests for functionality of the ChatConversationPanel.
+ *
+ * @author Danny van Heumen
+ */
+public class ChatConversationPanelTest
+    extends TestCase
+{
+
+    /**
+     * Test for various better and worse pieces of HTML to test the resilience
+     * of the pattern.
+     */
+    public void testHtmlSnippetsOnTextToReplacePattern()
+    {
+        final HashMap<String, String[]> tests = new HashMap<String, String[]>();
+        tests.put("just a piece of text",
+            new String[] {"just a piece of text", ""});
+        tests.put(">another piece of text",
+            new String[] {">another piece of text", ""});
+        tests.put("<another piece of text",
+            new String[] {"", ""});
+        tests.put("<another piece> of text",
+            new String[] {"", " of text", ""});
+        tests.put("<another attribute=\"piece\"> of text",
+            new String[] {"", " of text", ""});
+        tests.put("<another attribute=\"<\"> of text",
+            new String[] {"", " of text", ""});
+        tests.put("piece of text<tag>'nother piece</tag>stuff at the end",
+            new String[]
+            {"piece of text", "'nother piece", "stuff at the end", "" });
+        tests.put("<br />", new String[] {"", ""});
+        tests.put("<br />text", new String[] {"", "text", ""});
+        tests.put("some<br />text", new String[] {"some", "text", ""});
+        tests.put("<img src=\"blablabla.jpg\" />",
+            new String[] {"", ""});
+        tests.put("some<img src=\"blablabla.jpg\" />",
+            new String[] {"some", ""});
+        tests.put("some<img src=\"blablabla.jpg\" />foobar",
+            new String[] {"some", "foobar", ""});
+        tests.put(">some text between cut-off tags<",
+            new String[] {">some text between cut-off tags", ""});
+        tests.put("<some text between pointy brackets>",
+            new String[] {"", ""});
+        tests.put("fake &lt;br/&gt; tag",
+            new String[] {"fake &lt;br/&gt; tag", ""});
+        tests.put("fake &lt;br/> tag",
+            new String[] {"fake &lt;br/> tag", ""});
+        tests.put("fake <br/&gt; tag",
+            new String[] {"fake ", ""});
+        tests.put("a piece <b>of <u>formatted</u> text for </b>testing...",
+            new String[] {"a piece ", "of ", "formatted", " text for ",
+                "testing...", ""});
+        tests.put("a piece <a href=\"www.google.com?query=blabla#blabla\">"
+            + "www.google.com</a> hyperlinked text",
+            new String[] {"a piece ", "www.google.com", " hyperlinked text",
+                ""});
+        tests.put("<another attribute=\">\"> of text",
+            new String[] {"", " of text", ""});
+        tests.put("<a name=\"Click here ><\" href=\"www.google.com\">"
+            + "For a treat</a> or something ...",
+            new String[] {"", "For a treat", " or something ...", ""});
+        tests.put("and here is <a \"some weird syntax\"> to test",
+            new String[] {"and here is ", " to test", ""});
+        tests.put("and here <option name=\"opt\" checked> checked option",
+            new String[] {"and here ", " checked option", ""});
+        tests.put("incomplete <img href=\"www.goo",
+            new String[] {"incomplete ", ""});
+        tests.put("incomplete <img href=\"www.goo     >  <a href=\">test",
+            new String[] {"incomplete ", "test", ""});
+        tests.put("\"blablabla\">See if this text is ignored ...",
+            new String[] {"\"blablabla\">See if this text is ignored ...", ""});
+        tests.put("bla\">See if this<img src=\"test1\">test2</img>",
+            new String[] {"bla\">See if this", "test2", ""});
+        tests.put("<the-end", new String[] {"", ""});
+        tests.put("&lt;this-is-not-a-tag>",
+            new String[] {"&lt;this-is-not-a-tag>", ""});
+        tests.put("<this-is-a-tag>", new String[] {"", ""});
+
+        for (final Entry<String, String[]> entry : tests.entrySet())
+        {
+            final String input = entry.getKey();
+            int index = 0;
+            final Matcher matcher =
+                ChatConversationPanel.TEXT_TO_REPLACE_PATTERN.matcher(input);
+            while (matcher.find())
+            {
+                final String piece = matcher.group(1);
+                Assert.assertEquals("INPUT [[" + input + "]]:",
+                    entry.getValue()[index], piece);
+                index++;
+            }
+            // ensure that we have checked all predicted pieces
+            Assert.assertEquals(entry.getValue().length, index);
+        }
+    }
+}