From 18d198f6b67633b8af1c6031a751a4d46d4c6d5b Mon Sep 17 00:00:00 2001
From: mrange <marten_range@hotmail.com>
Date: Thu, 3 May 2018 13:51:47 +0200
Subject: [PATCH] Node.Text optimization

Reuses existing TextNode if available.
---
 Ooui/Node.cs       |  8 ++++++++
 Tests/NodeTests.cs | 44 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/Ooui/Node.cs b/Ooui/Node.cs
index 4d9ad8c..d1d8960 100644
--- a/Ooui/Node.cs
+++ b/Ooui/Node.cs
@@ -35,6 +35,14 @@ namespace Ooui
                 return sb.ToString ();
             }
             set {
+                if (Children.Count == 1) {
+                    var textNode = Children[0] as TextNode;
+                    if (textNode != null) {
+                        textNode.Text = value;
+                        return;
+                    }
+                }
+
                 ReplaceAll (new TextNode (value ?? ""));
             }
         }
diff --git a/Tests/NodeTests.cs b/Tests/NodeTests.cs
index 20a480a..6050bed 100644
--- a/Tests/NodeTests.cs
+++ b/Tests/NodeTests.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Text;
 
 #if NUNIT
 using NUnit.Framework;
@@ -68,5 +69,48 @@ namespace Tests
             p.Receive (Message.Event (b.Id, "change", "please work"));
             Assert.AreEqual ("please work", b.Value);
         }
+
+        [TestMethod]
+        public void Text ()
+        {
+            var div = new Div ();
+
+            // Log tracks all messages sent due to updates
+            var log = new StringBuilder ();
+            log.AppendLine ();
+            void Parent_MessageSent (Message obj)
+            {
+                log.AppendLine (obj.ToString ());
+            }
+            div.MessageSent += Parent_MessageSent;
+
+            var divId = div.Id;
+
+            log.AppendLine ("#1 - Inserts new text node");
+            div.Text = "Hello";
+
+            Assert.AreEqual (1, div.Children.Count);
+            var text = div.Children[0];
+            var textId = text.Id;
+
+            Assert.AreEqual ("Hello", div.Text);
+            Assert.AreEqual ("Hello", text.Text);
+
+            log.AppendLine ("#2 - Sets text node text to There");
+            div.Text = "There";
+            Assert.AreEqual ("There", div.Text);
+            Assert.AreEqual ("There", text.Text);
+
+            var expected = string.Format(@"
+#1 - Inserts new text node
+{{""m"":""call"",""id"":""{0}"",""k"":""insertBefore"",""v"":[""{1}"",null]}}
+#2 - Sets text node text to There
+{{""m"":""set"",""id"":""{1}"",""k"":""data"",""v"":""There""}}
+", divId, textId).Replace ("\r\n", "\n");
+
+            var actual = log.ToString ().Replace ("\r\n", "\n");
+            Assert.AreEqual (expected, actual);
+        }
+
     }
 }