From d8ab6b738ebd46d572aca8aec1c3adef86d4c56d Mon Sep 17 00:00:00 2001
From: skalogryz <skalogryz@8e941d3f-bd1b-0410-a28a-d453659cc2b4>
Date: Sun, 26 Jul 2020 17:50:22 +0000
Subject: [PATCH] richmemo: fix font matching logic, preventing infinite loop.
 updating GetTextAttribute policy for cases when there's no text

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@7570 8e941d3f-bd1b-0410-a28a-d453659cc2b4
---
 components/richmemo/cocoa/cocoarichmemo.pas | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/components/richmemo/cocoa/cocoarichmemo.pas b/components/richmemo/cocoa/cocoarichmemo.pas
index b76e1aacf..ed1cab4f0 100644
--- a/components/richmemo/cocoa/cocoarichmemo.pas
+++ b/components/richmemo/cocoa/cocoarichmemo.pas
@@ -247,6 +247,16 @@ begin
   if not Assigned(view) then Exit;
 
   txt:=view.textStorage;
+  if (txt.length = 0) then begin
+    // there's no text! using the control information
+    Params.Name := txt.font.displayName.UTF8String;
+    Params.Size := Round(txt.font.pointSize);
+    Params.HasBkClr := false;
+    exit;
+  end;
+
+  if (TextStart >= txt.length) then
+    TextStart := txt.length;
   dict:=GetDict(txt, textStart);
   ReadNSFontParams(dict, prm);
   if Assigned(prm.font) then begin
@@ -335,6 +345,7 @@ begin
       trt:=trt and (not fallback[i]);
       fd:=fd.fontDescriptorWithSymbolicTraits(trt);
       fdd:=fd.matchingFontDescriptorWithMandatoryKeys(nil);
+      inc(i);
     end;
     Result:=fdd;
   finally