From 0f45a4808764ba3bbe4b7fdc13d63c146d01edfc Mon Sep 17 00:00:00 2001
From: Rene Gollent <rene@gollent.com>
Date: Sun, 28 Dec 2014 17:20:05 -0500
Subject: [PATCH] Debugger: Fix #11669.

SourceView:
- When calculating line widths for scrollbar calculation purposes, tabstop
  offsets weren't being correctly taken into account, which would result
  in lines being computed as shorter than they actually were. Depending
  on the content of the file, the horizontal scrollbar would consequently
  be configured improperly in some cases.
---
 .../gui/team_window/SourceView.cpp            | 24 +++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/src/apps/debugger/user_interface/gui/team_window/SourceView.cpp b/src/apps/debugger/user_interface/gui/team_window/SourceView.cpp
index 88d8ddc1b1..0beeaf7347 100644
--- a/src/apps/debugger/user_interface/gui/team_window/SourceView.cpp
+++ b/src/apps/debugger/user_interface/gui/team_window/SourceView.cpp
@@ -330,6 +330,8 @@ private:
 			};
 
 			float				_MaxLineWidth();
+	inline	float				_FormattedLineWidth(const char* line) const;
+
 			void				_DrawLineSyntaxSection(const char* line,
 									int32 length, int32& _column,
 									BPoint& _offset);
@@ -1523,16 +1525,30 @@ SourceView::TextView::_MaxLineWidth()
 
 	fMaxLineWidth = 0;
 	if (fSourceCode != NULL) {
-		for (int32 i = 0; const char* line = fSourceCode->LineAt(i); i++) {
-			fMaxLineWidth = std::max(fMaxLineWidth,
-				fFontInfo->font.StringWidth(line));
-		}
+		for (int32 i = 0; const char* line = fSourceCode->LineAt(i); i++)
+			fMaxLineWidth = std::max(fMaxLineWidth, _FormattedLineWidth(line));
 	}
 
 	return fMaxLineWidth;
 }
 
 
+float
+SourceView::TextView::_FormattedLineWidth(const char* line) const
+{
+	int32 column = 0;
+	int32 i = 0;
+	for (; line[i] != '\0'; i++) {
+		if (line[i] == '\t')
+			column = _NextTabStop(column);
+		else
+			++column;
+	}
+
+	return column * fCharacterWidth;
+}
+
+
 void
 SourceView::TextView::_DrawLineSyntaxSection(const char* line, int32 length,
 	int32& _column, BPoint& _offset)