Three fixes in RichTextBox, one GenerateRTF, two ContentResized.

In GenerateRTF, check tag != null before trying to generate anything based on it. Not sure
why it hasn't been a problem before, but either way I was getting NullReferenceExceptions
because of it today.

Run ContentSizeChanged() when either width or height changes, irrespective of Multiline status.
This fixes various problems with stuff jumping around vertically.

Correct ContentSizeChanged to consider the left and right margins instead of the left margin twice.
Was probably a typo at an earlier stage, otherwise would have been a * 2.

1 files changed, 4 insertions, 6 deletions

diff --git a/mcs/class/System.Windows.Forms/System.Windows.Forms/RichTextBox.cs b/mcs/class/System.Windows.Forms/System.Windows.Forms/RichTextBox.cs
index 63eb9afa609..f553bc498b4 100644
--- a/mcs/class/System.Windows.Forms/System.Windows.Forms/RichTextBox.cs
+++ b/mcs/class/System.Windows.Forms/System.Windows.Forms/RichTextBox.cs
@@ -143,12 +143,10 @@ namespace System.Windows.Forms {
 		}
 
 		private void ContentWidthChanged (object sender, EventArgs e) {
-			if (!Multiline)
-				ContentSizeChanged();
+			ContentSizeChanged();
 		}
 		private void ContentHeightChanged (object sender, EventArgs e) {
-			if (Multiline)
-				ContentSizeChanged();
+			ContentSizeChanged();
 		}
 
 		private void ContentSizeChanged () {
@@ -160,7 +158,7 @@ namespace System.Windows.Forms {
 				if (Multiline) {
 					width = Width; // yes, this is the insanity that is the traditional .Net implementation...
 				} else {
-					width = document.Width + document.left_margin + document.left_margin + Width - ClientRectangle.Width;
+					width = document.Width + document.left_margin + document.right_margin + Width - ClientRectangle.Width;
 				}
 
 				ContentsResizedEventArgs args = new ContentsResizedEventArgs (new Rectangle (Left, Top, width, height));
@@ -2594,7 +2592,7 @@ namespace System.Windows.Forms {
 						sb.Append(" ");
 					}
 
-					while (pos < line_len) {
+					while (pos < line_len && tag != null) {
 						length = sb.Length;
 
 						if (tag.Font != font) {