Bug 16979 - StringBuilder.AppendFormat != string.Format
Summary: StringBuilder.AppendFormat != string.Format
Alias: None
Product: Class Libraries
Classification: Mono
Component: General ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Marek Safar
Depends on:
Reported: 2013-12-28 21:03 UTC by alex
Modified: 2014-01-01 09:35 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description alex 2013-12-28 21:03:10 UTC
var sb = new StringBuilder();

// This fails:
sb.AppendFormat ("<span color=\"#{0:x2}{1:x2}{2:x2}\">", 123, 1, 16);

// This works:
sb.Append(string.Format("<span color=\"#{0:x2}{1:x2}{2:x2}\">", 123, 1, 16));

Null-ref exception
  at System.String.FormatHelper (System.Text.StringBuilder result, IFormatProvider provider, System.String format, System.Object[] args) [0x00000] in <filename unknown>:0 
  at System.Text.StringBuilder.AppendFormat (IFormatProvider provider, System.String format, System.Object[] args) [0x00000] in <filename unknown>:0 
  at System.Text.StringBuilder.AppendFormat (System.String format, System.Object arg0, System.Object arg1, System.Object arg2) [0x00000] in <filename unknown>:0 
  at MonoDevelop.D.Gui.DToolTipProvider.DCodeToMarkup (Mono.TextEditor.Highlighting.ColorScheme st, System.String code) [0x000f3] in /home/lx/Dokumente/Projects/Mono-D/MonoDevelop.DBinding/Gui/DToolTipProvider.cs:170 
  at MonoDevelop.D.Gui.DToolTipProvider.CreateTooltip (Mono.TextEditor.TextEditor editor, D_Parser.Resolver.AbstractType t, Int32 offset, ModifierType modifierState) [0x00021] in /home/lx/Dokumente/Projects/Mono-D/MonoDevelop.DBinding/Gui/DToolTipProvider.cs:136 
  at MonoDevelop.D.Gui.DToolTipProvider.CreateTooltipWindow (Mono.TextEditor.TextEditor editor, Int32 offset, ModifierType modifierState, Mono.TextEditor.TooltipItem item) [0x00063] in /home/lx/Dokumente/Projects/Mono-D/MonoDevelop.DBinding/Gui/DToolTipProvider.cs:68 
  at MonoDevelop.D.Gui.DToolTipProvider.ShowTooltipWindow (Mono.TextEditor.TextEditor editor, Int32 offset, ModifierType modifierState, Int32 mouseX, Int32 mouseY, Mono.TextEditor.TooltipItem item) [0x0002b] in /home/lx/Dokumente/Projects/Mono-D/MonoDevelop.DBinding/Gui/DToolTipProvider.cs:90 
  at Mono.TextEditor.TextArea.TooltipTimer () [0x00185] in /run/media/lx/Home.alt/lx/Dokumente/Projects/monodevelop/main/src/core/Mono.Texteditor/Mono.TextEditor/Gui/TextArea.cs:2750
Comment 1 Marek Safar 2014-01-01 09:35:57 UTC
Works for me with Mono 3.2.5