From 7d86c6e5b1a5ed510da6fe784193eb4df43c3113 Mon Sep 17 00:00:00 2001
From: Roy Qu <royqh1979@gmail.com>
Date: Sun, 3 Apr 2022 11:54:07 +0800
Subject: [PATCH] - fix: crash when editing txt file and input symbol at the
 beginning of a line

---
 NEWS.md                |  1 +
 RedPandaIDE/editor.cpp | 52 ++++++++++++++++++++++--------------------
 2 files changed, 28 insertions(+), 25 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 0da4ce31..4203d188 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -5,6 +5,7 @@ Red Panda C++ Version 1.0.3
   - enhancement: shift+ctrl+down/up to move currenlt selection lines up / down
   - fix: can't compile under linux
   - enhancement: support Devcie Pixel Ratio ( for linux )
+  - fix: crash when editing txt file and input symbol at the beginning of a line
 
 Red Panda C++ Version 1.0.2
   - enhancement: press tab in column mode won't exit column mode
diff --git a/RedPandaIDE/editor.cpp b/RedPandaIDE/editor.cpp
index 956028b2..41724ce5 100644
--- a/RedPandaIDE/editor.cpp
+++ b/RedPandaIDE/editor.cpp
@@ -2001,31 +2001,33 @@ bool Editor::handleSymbolCompletion(QChar key)
         return false;
 
     //todo: better methods to detect current caret type
-    if (caretX() <= 1) {
-        if (caretY()>1) {
-            if (highlighter()->isLastLineCommentNotFinished(lines()->ranges(caretY() - 2).state))
-                return false;
-            if (highlighter()->isLastLineStringNotFinished(lines()->ranges(caretY() - 2).state)
-                    && (key!='\"') && (key!='\''))
-                return false;
-        }
-    } else {
-        BufferCoord  HighlightPos = BufferCoord{caretX()-1, caretY()};
-        // Check if that line is highlighted as  comment
-        PSynHighlighterAttribute Attr;
-        QString Token;
-        bool tokenFinished;
-        SynHighlighterTokenType tokenType;
-        if (getHighlighterAttriAtRowCol(HighlightPos, Token, tokenFinished, tokenType,Attr)) {
-            if ((tokenType == SynHighlighterTokenType::Comment) && (!tokenFinished))
-                return false;
-            if ((tokenType == SynHighlighterTokenType::String) && (!tokenFinished)
-                    && (key!='\'') && (key!='\"') && (key!='(') && (key!=')'))
-                return false;
-            if (( key=='<' || key =='>') && (mParser && !mParser->isIncludeLine(lineText())))
-                return false;
-            if ((key == '\'') && (Attr->name() == "SYNS_AttrNumber"))
-                return false;
+    if (highlighter()) {
+        if (caretX() <= 1) {
+            if (caretY()>1) {
+                if (highlighter()->isLastLineCommentNotFinished(lines()->ranges(caretY() - 2).state))
+                    return false;
+                if (highlighter()->isLastLineStringNotFinished(lines()->ranges(caretY() - 2).state)
+                        && (key!='\"') && (key!='\''))
+                    return false;
+            }
+        } else {
+            BufferCoord  HighlightPos = BufferCoord{caretX()-1, caretY()};
+            // Check if that line is highlighted as  comment
+            PSynHighlighterAttribute Attr;
+            QString Token;
+            bool tokenFinished;
+            SynHighlighterTokenType tokenType;
+            if (getHighlighterAttriAtRowCol(HighlightPos, Token, tokenFinished, tokenType,Attr)) {
+                if ((tokenType == SynHighlighterTokenType::Comment) && (!tokenFinished))
+                    return false;
+                if ((tokenType == SynHighlighterTokenType::String) && (!tokenFinished)
+                        && (key!='\'') && (key!='\"') && (key!='(') && (key!=')'))
+                    return false;
+                if (( key=='<' || key =='>') && (mParser && !mParser->isIncludeLine(lineText())))
+                    return false;
+                if ((key == '\'') && (Attr->name() == "SYNS_AttrNumber"))
+                    return false;
+            }
         }
     }