TSynEdit crashes when loading text

[domasz]

When I click this button twice the program crashes. Might be something with highlighters (TSynMultiSyn, TSynPHPSyn, TSynHTMLSyn).

Code: Pascal  [Select][+][-]

1. procedure TForm1.Button1Click(Sender: TObject);
2. var Str: String;
3.     L: TStringList;
4. begin
5.   L := TStringList.Create;
6.   L.LoadFromFile('test.htm');
7.  
8.   Str := L.Text;
9.   L.Free;
10.  
11.  SynEdit1.Text:=Str; //crashes
12. end;
13.  

Code: Pascal  [Select][+][-]

1.   object SynMultiSyn1: TSynMultiSyn
2.     Enabled = False
3.     Schemes = <    
4.       item
5.         StartExpr = '<style>'
6.         EndExpr = '</style>'
7.         Highlighter = SynCssSyn1
8.         MarkerAttri.Background = clNone
9.         MarkerAttri.Foreground = 16744448
10.       end        
11.       item
12.         StartExpr = '<\?php'
13.         EndExpr = '\?>'
14.         Highlighter = SynPHPSyn1
15.         MarkerAttri.Background = clNone
16.         MarkerAttri.Foreground = 16512
17.       end>
18.     DefaultHighlighter = SynHTMLSyn1
19.     Left = 592
20.     Top = 40
21.   end

Attached is super simple demo.

[Martin_fr]

I can reproduce...

It seems something in the Multi-HL. Not sure yet

[Martin_fr]

Ideally report on the bug tracker please

[domasz]

Ideally report on the bug tracker please

Not sure if I did it right. Don't know how to post files there.
https://gitlab.com/freepascal.org/lazarus/lazarus/-/issues/40292

[Martin_fr]

ok, thanks

[Martin_fr]

A temporary patch. I still need to do some testing.

Code: Diff  [Select][+][-]

1. diff --git a/components/synedit/synhighlightermulti.pas b/components/synedit/synhighlightermulti.pas
2. index 1343e5d554..ca662dc37d 100644
3. --- a/components/synedit/synhighlightermulti.pas
4. +++ b/components/synedit/synhighlightermulti.pas
5. @@ -845,22 +845,22 @@ procedure TSynHLightMultiVirtualLines.RealLinesDeleted(AIndex, ACount: Integer);
6.      // Real-lines starting in the middle of the Section
7.      CountInSection := Min(AIndex + ACount, p^.EndPos.y + 1) - AIndex;
8.      FirstVLine := p^.VirtualLine + AIndex - p^.StartPos.y;
9. -    PrevEndVLine := p^.VirtualLine + p^.EndPos.y - p^.EndPos.y;
10. +    PrevEndVLine := p^.VirtualLine + p^.EndPos.y - p^.StartPos.y;
11.      p^.EndPos.y := p^.EndPos.y - CountInSection;
12.      inc(i);
13.      if i = FSectionList.Count then begin
14.        DelVLines;
15.        exit;
16.      end;
17.      p := FSectionList.PSections[i];
18.     VLineCount := CountInSection;
19.    end;
20.    while p^.EndPos.y < AIndex + ACount do begin
21.      // Completly delete node (All Real lines deleted)
22.      VLineCount := VLineCount + p^.EndPos.y - p^.StartPos.y + 1;
23.      if PrevEndVLine = p^.VirtualLine then
24.        dec(VLineCount);
25. -    PrevEndVLine := p^.VirtualLine + p^.EndPos.y - p^.EndPos.y;
26. +    PrevEndVLine := p^.VirtualLine + p^.EndPos.y - p^.StartPos.y;
27.      FSectionList.Delete(i);
28.      if i = FSectionList.Count then begin
29.        DelVLines;
30.  
31.  

[domasz]

Seems to work great, thank you for such a quick fix!

I tried it with hundreds of files from real websites and I found no problems.

[Martin_fr]

Found a few other issues too. For patch, see the commit mentioned in the reported issue.