Fix for 216437: [Formatter] Shift left/right incorrect in Mixed tab policy/indentation mode

7 files changed, 408 insertions, 49 deletions

diff --git a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/ShiftActionTest.java b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/ShiftActionTest.java
new file mode 100644
index 00000000000..70e91f7b9d5
--- /dev/null
+++ b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/ShiftActionTest.java
@@ -0,0 +1,157 @@
+/*******************************************************************************
+ * Copyright (c) 2008 Wind River Systems, Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Anton Leherbauer (Wind River Systems) - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.ui.tests.text;
+
+import java.util.ListResourceBundle;
+
+import junit.extensions.TestSetup;
+import junit.framework.Test;
+import junit.framework.TestSuite;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.resources.ResourcesPlugin;
+import org.eclipse.core.runtime.NullProgressMonitor;
+import org.eclipse.core.runtime.Path;
+import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.source.SourceViewer;
+import org.eclipse.ui.texteditor.ShiftAction;
+
+import org.eclipse.cdt.core.formatter.DefaultCodeFormatterConstants;
+import org.eclipse.cdt.core.model.ICProject;
+import org.eclipse.cdt.core.testplugin.CProjectHelper;
+import org.eclipse.cdt.ui.tests.BaseUITestCase;
+import org.eclipse.cdt.ui.tests.text.MarkOccurrenceTest.MarkOccurrenceTestSetup;
+
+import org.eclipse.cdt.internal.ui.editor.CEditor;
+
+/**
+ * Test the Shift left/right actions.
+ * 
+ * @since 5.0
+ */
+public class ShiftActionTest extends BaseUITestCase {
+	private static final String PROJECT= "ShiftTests";
+	private static final String FILE = "shiftTest.c";
+
+	private static final class EmptyBundle extends ListResourceBundle {
+		protected Object[][] getContents() {
+			return new Object[0][];
+		}
+	}
+
+	protected static class ShiftTestSetup extends TestSetup {
+
+		private ICProject fCProject;
+
+		public ShiftTestSetup(Test test) {
+			super(test);
+		}
+		
+		protected void setUp() throws Exception {
+			super.setUp();
+			
+			fCProject= CProjectHelper.createCProject(PROJECT, null);
+			fCProject.setOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR, DefaultCodeFormatterConstants.MIXED);
+			fCProject.setOption(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE, String.valueOf(8));
+			fCProject.setOption(DefaultCodeFormatterConstants.FORMATTER_INDENTATION_SIZE, String.valueOf(4));
+			IFile file= EditorTestHelper.createFile(fCProject.getProject(), FILE, "", new NullProgressMonitor());
+		}
+
+		protected void tearDown () throws Exception {
+			EditorTestHelper.closeAllEditors();
+			if (fCProject != null) {
+				CProjectHelper.delete(fCProject);
+			}
+			super.tearDown();
+		}
+	}
+	
+	private static final Class THIS= ShiftActionTest.class;
+	public static Test suite() {
+		return new ShiftTestSetup(new TestSuite(THIS));
+	}
+
+	private CEditor fEditor;
+	private SourceViewer fSourceViewer;
+	private IDocument fDocument;
+	private MarkOccurrenceTestSetup fProjectSetup;
+
+	/*
+	 * @see junit.framework.TestCase#setUp()
+	 */
+	protected void setUp() throws Exception {
+		if (!ResourcesPlugin.getWorkspace().getRoot().exists(new Path(PROJECT))) {
+			fProjectSetup= new MarkOccurrenceTestSetup(this);
+			fProjectSetup.setUp();
+		}
+		fEditor= (CEditor) EditorTestHelper.openInEditor(ResourceTestHelper.findFile(PROJECT + '/' + FILE), true);
+		fSourceViewer= EditorTestHelper.getSourceViewer(fEditor);
+		fDocument= fSourceViewer.getDocument();
+		super.setUp();
+	}
+	
+	/*
+	 * @see junit.framework.TestCase#tearDown()
+	 */
+	protected void tearDown() throws Exception {
+		if (fProjectSetup != null) {
+			fProjectSetup.tearDown();
+		}
+		super.tearDown();
+	}
+	
+	private void shiftLeft() throws Exception {
+		new ShiftAction(new EmptyBundle(), "prefix", fEditor, SourceViewer.SHIFT_LEFT).run();
+	}
+
+	private void shiftRight() throws Exception {
+		new ShiftAction(new EmptyBundle(), "prefix", fEditor, SourceViewer.SHIFT_RIGHT).run();
+	}
+
+	private void selectAll() {
+		fSourceViewer.setSelectedRange(0, fDocument.getLength());
+	}
+
+	//void f() {
+	//    for(;;) {
+	//}
+	
+	//    void f() {
+	//	for(;;) {
+	//    }
+	public void testShiftRight() throws Exception {
+		StringBuffer[] contents= getContentsForTest(2);
+		String before= contents[0].toString();
+		String after= contents[1].toString();
+		fDocument.set(before);
+		selectAll();
+		shiftRight();
+		assertEquals(after, fDocument.get());
+	}
+
+	//    void f() {
+	//	for(;;) {
+	//    }
+
+	//void f() {
+	//    for(;;) {
+	//}
+	public void testShiftLeft() throws Exception {
+		StringBuffer[] contents= getContentsForTest(2);
+		String before= contents[0].toString();
+		String after= contents[1].toString();
+		fDocument.set(before);
+		selectAll();
+		shiftLeft();
+		assertEquals(after, fDocument.get());
+	}
+
+}
diff --git a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/TextTestSuite.java b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/TextTestSuite.java
index d794ea94819..e19bb822035 100644
--- a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/TextTestSuite.java
+++ b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/TextTestSuite.java
@@ -33,6 +33,7 @@ public class TextTestSuite extends TestSuite {
 		addTest(BracketInserterTest.suite());
 		addTest(IndentActionTest.suite());
 		addTest(FormatActionTest.suite());
+		addTest(ShiftActionTest.suite());
 		addTest(CodeFormatterTest.suite());
 		addTest(CIndenterTest.suite());
 		
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/actions/IndentAction.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/actions/IndentAction.java
index e1d414ba23a..547bb9437ac 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/actions/IndentAction.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/actions/IndentAction.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2007 IBM Corporation and others.
+ * Copyright (c) 2000, 2008 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -269,11 +269,12 @@ public class IndentAction extends TextEditorAction {
 		String currentIndent= document.get(offset, length);
 		
 		// if we are right before the text start / line end, and already after the insertion point
-		// then just insert a tab.
+		// then just shift to the right
 		if (fIsTabAction && caret == end && whiteSpaceLength(currentIndent) >= whiteSpaceLength(indent)) {
-			String tab= getTabEquivalent();
-			document.replace(caret, 0, tab);
-			fCaretOffset= caret + tab.length();
+			int indentWidth= whiteSpaceLength(currentIndent) + getIndentSize();
+			String replacement= IndentUtil.changePrefix(currentIndent.trim(), indentWidth, getTabSize(), useSpaces());
+			document.replace(offset, length, replacement);
+			fCaretOffset= offset + replacement.length();
 			return true;
 		}
 		
@@ -329,36 +330,17 @@ public class IndentAction extends TextEditorAction {
 	private int whiteSpaceLength(String indent) {
 		if (indent == null)
 			return 0;
-		else {
-			int size= 0;
-			int l= indent.length();
-			int tabSize= getTabSize();
-			
-			for (int i= 0; i < l; i++)
-				size += indent.charAt(i) == '\t' ? tabSize : 1;
-			return size;
-		}
+		return IndentUtil.computeVisualLength(indent, getTabSize());
 	}
 
 	/**
-	 * Returns a tab equivalent, either as a tab character or as spaces, depending on the editor and
+	 * Returns whether spaces should be used exclusively for indentation, depending on the editor and
 	 * formatter preferences.
 	 * 
-	 * @return a string representing one tab in the editor, never <code>null</code>
+	 * @return <code>true</code> if only spaces should be used
 	 */
-	private String getTabEquivalent() {
-		String tab;
-		if (CCorePlugin.SPACE.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR))) {
-			int size= getTabSize();
-			StringBuffer buf= new StringBuffer();
-			for (int i= 0; i< size; i++)
-				buf.append(' ');
-			tab= buf.toString();
-		} else {
-			tab= "\t"; //$NON-NLS-1$
-		}
-	
-		return tab;
+	private boolean useSpaces() {
+		return CCorePlugin.SPACE.equals(getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR));
 	}
 	
 	/**
@@ -372,6 +354,16 @@ public class IndentAction extends TextEditorAction {
 	}
 
 	/**
+	 * Returns the indent size used by the editor, which is deduced from the
+	 * formatter preferences.
+	 * 
+	 * @return the indent size as defined in the current formatter preferences
+	 */
+	private int getIndentSize() {
+		return getCoreFormatterOption(DefaultCodeFormatterConstants.FORMATTER_INDENTATION_SIZE, 4);
+	}
+
+	/**
 	 * Returns <code>true</code> if empty lines should be indented, <code>false</code> otherwise.
 	 * 
 	 * @return <code>true</code> if empty lines should be indented, <code>false</code> otherwise
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CEditor.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CEditor.java
index 5de7312cb03..133c728683e 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CEditor.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CEditor.java
@@ -175,6 +175,7 @@ import org.eclipse.cdt.ui.text.ICPartitions;
 import org.eclipse.cdt.ui.text.folding.ICFoldingStructureProvider;
 
 import org.eclipse.cdt.internal.core.model.ASTCache.ASTRunnable;
+import org.eclipse.cdt.internal.corext.util.CodeFormatterUtil;
 
 import org.eclipse.cdt.internal.ui.CPluginImages;
 import org.eclipse.cdt.internal.ui.ICHelpContextIds;
@@ -1093,8 +1094,6 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IC
 	public static final String INACTIVE_CODE_ENABLE = "inactiveCodeEnable"; //$NON-NLS-1$
 	/** Preference key for inactive code painter color */
 	public static final String INACTIVE_CODE_COLOR = "inactiveCodeColor"; //$NON-NLS-1$
-	/** Preference key for inserting spaces rather than tabs */
-	public final static String SPACES_FOR_TABS = DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR;
 	/** Preference key for automatically closing strings */
 	private final static String CLOSE_STRINGS = PreferenceConstants.EDITOR_CLOSE_STRINGS;
 	/** Preference key for automatically closing brackets and parenthesis */
@@ -1211,6 +1210,13 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IC
 		if (fCEditorErrorTickUpdater != null) {
 			fCEditorErrorTickUpdater.updateEditorImage(getInputCElement());
 		}
+		
+		ICElement element= getInputCElement();
+		if (element instanceof ITranslationUnit) {
+			fBracketMatcher.configure(((ITranslationUnit)element).getLanguage());
+		} else {
+			fBracketMatcher.configure(null);
+		}
 	}
 
 	/**
@@ -1342,14 +1348,6 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IC
 					return;
 				}
 
-				if (SPACES_FOR_TABS.equals(property)) {
-					if (isTabsToSpacesConversionEnabled())
-						installTabsToSpacesConverter();
-					else
-						uninstallTabsToSpacesConverter();
-					return;
-				}
-
 				if (PreferenceConstants.EDITOR_TEXT_HOVER_MODIFIERS.equals(property))
 					updateHoverBehavior();
 
@@ -1392,7 +1390,7 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IC
 						uninstallTabsToSpacesConverter();
 						installTabsToSpacesConverter();
 					} else {
-						updateIndentPrefixes();
+						updateIndentationMode();
 					}
 					return;
 				}
@@ -1723,8 +1721,21 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IC
 			} else
 				tabToSpacesConverter.setLineTracker(new DefaultLineTracker());
 			((ITextViewerExtension7)sourceViewer).setTabsToSpacesConverter(tabToSpacesConverter);
-			updateIndentPrefixes();
+			updateIndentationMode();
+		}
+	}
+
+	private void updateIndentationMode() {
+		ISourceViewer sourceViewer= getSourceViewer();
+		if (sourceViewer instanceof CSourceViewer) {
+			CSourceViewer cSourceVieer= (CSourceViewer) sourceViewer;
+			ICElement element= getInputCElement();
+			ICProject project= element == null ? null : element.getCProject();
+			final int indentWidth= CodeFormatterUtil.getIndentWidth(project);
+			final boolean useSpaces= isTabsToSpacesConversionEnabled();
+			cSourceVieer.configureIndentation(indentWidth, useSpaces);
 		}
+		super.updateIndentPrefixes();
 	}
 
 	/*
@@ -1736,9 +1747,9 @@ public class CEditor extends TextEditor implements ISelectionChangedListener, IC
 		ICProject project= element == null ? null : element.getCProject();
 		String option;
 		if (project == null)
-			option= CCorePlugin.getOption(SPACES_FOR_TABS);
+			option= CCorePlugin.getOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR);
 		else
-			option= project.getOption(SPACES_FOR_TABS, true);
+			option= project.getOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR, true);
 		return CCorePlugin.SPACE.equals(option);
 	}
 
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CSourceViewer.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CSourceViewer.java
index 2ee2a2b5c44..006f736fc70 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CSourceViewer.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/CSourceViewer.java
@@ -18,7 +18,11 @@ import java.util.ArrayList;
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.jface.preference.PreferenceConverter;
+import org.eclipse.jface.text.BadLocationException;
+import org.eclipse.jface.text.DocumentRewriteSession;
+import org.eclipse.jface.text.DocumentRewriteSessionType;
 import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.IDocumentExtension4;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.ITextPresentationListener;
 import org.eclipse.jface.text.Region;
@@ -35,6 +39,7 @@ import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.StyleRange;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.graphics.Color;
+import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.RGB;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Display;
@@ -51,11 +56,11 @@ import org.eclipse.cdt.internal.ui.text.CSourceViewerConfiguration;
 public class CSourceViewer extends ProjectionViewer implements IPropertyChangeListener {
 
     /** Show outline operation id. */
-    public static final int SHOW_OUTLINE = 101;
+    public static final int SHOW_OUTLINE= 101;
     /** Show type hierarchy operation id. */
-    public static final int SHOW_HIERARCHY = 102;
+    public static final int SHOW_HIERARCHY= 102;
     /** Show macro explorer operation id. */
-    public static final int SHOW_MACRO_EXPLORER = 103;
+    public static final int SHOW_MACRO_EXPLORER= 103;
     
     /** Presents outline. */
     private IInformationPresenter fOutlinePresenter;
@@ -111,6 +116,15 @@ public class CSourceViewer extends ProjectionViewer implements IPropertyChangeLi
 	 * Workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=195808
 	 */
 	private boolean fWasProjectionMode;
+	
+	/**
+	 * The configured indent width.
+	 */
+	private int fIndentWidth= 4;
+	/**
+	 * Flag indicating whether to use spaces exclusively for indentation.
+	 */
+	private boolean fUseSpaces;
 
 	/**
      * Creates new source viewer. 
@@ -152,6 +166,7 @@ public class CSourceViewer extends ProjectionViewer implements IPropertyChangeLi
 		}
 
 		super.configure(configuration);
+
 		if (configuration instanceof CSourceViewerConfiguration) {
 			CSourceViewerConfiguration cConfiguration= (CSourceViewerConfiguration)configuration;
 			fOutlinePresenter= cConfiguration.getOutlinePresenter(this);
@@ -164,6 +179,12 @@ public class CSourceViewer extends ProjectionViewer implements IPropertyChangeLi
 			if (fMacroExplorationPresenter != null) {
 				fMacroExplorationPresenter.install(this);
 			}
+			String[] defaultIndentPrefixes= (String[])fIndentChars.get(IDocument.DEFAULT_CONTENT_TYPE);
+			if (defaultIndentPrefixes != null && defaultIndentPrefixes.length > 0) {
+				final int indentWidth= cConfiguration.getIndentWidth(this);
+				final boolean useSpaces= cConfiguration.useSpacesOnly(this);
+				configureIndentation(indentWidth, useSpaces);
+			}
 		}
 		if (fPreferenceStore != null) {
 			fPreferenceStore.addPropertyChangeListener(this);
@@ -290,7 +311,7 @@ public class CSourceViewer extends ProjectionViewer implements IPropertyChangeLi
 	 * @see org.eclipse.jface.util.IPropertyChangeListener#propertyChange(org.eclipse.jface.util.PropertyChangeEvent)
 	 */
 	public void propertyChange(PropertyChangeEvent event) {
-		String property = event.getProperty();
+		String property= event.getProperty();
 		if (AbstractTextEditor.PREFERENCE_COLOR_FOREGROUND.equals(property)
 				|| AbstractTextEditor.PREFERENCE_COLOR_FOREGROUND_SYSTEM_DEFAULT.equals(property)
 				|| AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND.equals(property)
@@ -468,4 +489,114 @@ public class CSourceViewer extends ProjectionViewer implements IPropertyChangeLi
 			enableProjection();
 		}
 	}
+
+
+	/**
+	 * Configure the indentation mode for this viewer.
+	 * 
+	 * @param indentWidth  the indentation width
+	 * @param useSpaces  if <code>true</code>, only spaces are used for indentation
+	 */
+	public void configureIndentation(int indentWidth, boolean useSpaces) {
+		fIndentWidth= indentWidth;
+		fUseSpaces= useSpaces;
+	}
+
+	/*
+	 * @see org.eclipse.jface.text.TextViewer#shift(boolean, boolean, boolean)
+	 */
+	protected void shift(boolean useDefaultPrefixes, boolean right, boolean ignoreWhitespace) {
+		if (!useDefaultPrefixes) {
+			// simple shift case
+			adjustIndent(right, fIndentWidth, fUseSpaces);
+			return;
+		}
+		super.shift(useDefaultPrefixes, right, ignoreWhitespace);
+	}
+
+	/**
+	 * Increase/decrease indentation of current selection.
+	 * 
+	 * @param increase  if <code>true</code>, indent is increased by one unit
+	 * @param shiftWidth  width in spaces of one indent unit
+	 * @param useSpaces  if <code>true</code>, only spaces are used for indentation
+	 */
+	protected void adjustIndent(boolean increase, int shiftWidth, boolean useSpaces) {
+		if (fUndoManager != null) {
+			fUndoManager.beginCompoundChange();
+		}
+		IDocument d= getDocument();
+		DocumentRewriteSession rewriteSession= null;
+		try {
+			if (d instanceof IDocumentExtension4) {
+				IDocumentExtension4 extension= (IDocumentExtension4) d;
+				rewriteSession= extension.startRewriteSession(DocumentRewriteSessionType.SEQUENTIAL);
+			}
+
+			Point selection= getSelectedRange();
+
+			// perform the adjustment
+			int tabWidth= getTextWidget().getTabs();
+			int startLine= d.getLineOfOffset(selection.x);
+			int endLine= selection.y == 0 ? startLine : d.getLineOfOffset(selection.x + selection.y - 1);
+			for (int line= startLine; line <= endLine; ++line) {
+				IRegion lineRegion= d.getLineInformation(line);
+				String indent= IndentUtil.getCurrentIndent(d, line, false);
+				int indentWidth= IndentUtil.computeVisualLength(indent, tabWidth);
+				int newIndentWidth= Math.max(0, indentWidth + (increase ? shiftWidth : -shiftWidth));
+				String newIndent= IndentUtil.changePrefix(indent.trim(), newIndentWidth, tabWidth, useSpaces);
+				int commonLen= getCommonPrefixLength(indent, newIndent);
+				if (commonLen < Math.max(indent.length(), newIndent.length())) {
+					if (commonLen > 0) {
+						indent= indent.substring(commonLen);
+						newIndent= newIndent.substring(commonLen);
+					}
+					final int offset= lineRegion.getOffset() + commonLen;
+					if (!increase && newIndent.length() > indent.length() && indent.length() > 0) {
+						d.replace(offset, indent.length(), ""); //$NON-NLS-1$
+						d.replace(offset, 0, newIndent);
+					} else {
+						d.replace(offset, indent.length(), newIndent);
+					}
+				}
+			}
+			
+		} catch (BadLocationException x) {
+			// ignored
+		} finally {
+			if (rewriteSession != null) {
+				((IDocumentExtension4)d).stopRewriteSession(rewriteSession);
+			}
+			if (fUndoManager != null) {
+				fUndoManager.endCompoundChange();
+			}
+		}
+	}
+
+    /**
+     * Compute the length of the common prefix of two strings.
+     * 
+	 * @param s1
+	 * @param s2
+	 * @return the length of the common prefix
+	 */
+	private static int getCommonPrefixLength(String s1, String s2) {
+		final int l1= s1.length();
+		final int l2= s2.length();
+		int i= 0;
+		while (i < l1 && i < l2 && s1.charAt(i) == s2.charAt(i)) {
+			++i;
+		}
+		return i;
+	}
+
+	/*
+     * work around for memory leak in TextViewer$WidgetCommand
+     */
+    protected void updateTextListeners(WidgetCommand cmd) {
+        super.updateTextListeners(cmd);
+        cmd.preservedText= null;
+        cmd.event= null;
+        cmd.text= null;
+    }
 }
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/IndentUtil.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/IndentUtil.java
index d2093314ae4..75f44c92906 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/IndentUtil.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/editor/IndentUtil.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2005, 2007 IBM Corporation and others.
+ * Copyright (c) 2005, 2008 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -8,6 +8,7 @@
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *     Sergey Prigogin, Google
+ *     Anton Leherbauer (Wind River Systems)
  *******************************************************************************/
 package org.eclipse.cdt.internal.ui.editor;
 
@@ -618,4 +619,46 @@ public final class IndentUtil {
 		return computed.toString();
 	}
 
+	/**
+	 * Extends the string with whitespace to match displayed width.
+	 * @param prefix  add to this string
+	 * @param displayedWidth  the desired display width
+	 * @param tabWidth  the configured tab width
+	 * @param useSpaces  whether to use spaces only
+	 */
+	public static String changePrefix(String prefix, int displayedWidth, int tabWidth, boolean useSpaces) {
+		int column = computeVisualLength(prefix, tabWidth);
+		if (column > displayedWidth) {
+			return prefix;
+		}
+		final StringBuffer buffer = new StringBuffer(prefix);
+		appendIndent(buffer, displayedWidth, tabWidth, useSpaces, column);
+		return buffer.toString();
+	}
+
+	/**
+	 * Appends whitespace to given buffer such that its visual length equals the given width.
+	 * @param buffer  the buffer to add whitespace to
+	 * @param width  the desired visual indent width
+	 * @param tabWidth  the configured tab width
+	 * @param useSpaces  whether tabs should be substituted by spaces
+	 * @param startColumn  the column where to start measurement
+	 * @return StringBuffer
+	 */
+	private static StringBuffer appendIndent(StringBuffer buffer, int width, int tabWidth, boolean useSpaces, int startColumn) {
+		assert tabWidth > 0;
+		int tabStop = startColumn - startColumn % tabWidth;
+		int tabs = useSpaces ? 0 : (width-tabStop) / tabWidth;
+		for (int i = 0; i < tabs; ++i) {
+			buffer.append('\t');
+			tabStop += tabWidth;
+			startColumn = tabStop;
+		}
+		int spaces = width - startColumn;
+		for (int i = 0; i < spaces; ++i) {
+			buffer.append(' ');
+		}
+		return buffer;
+	}
+
 }
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/text/CSourceViewerConfiguration.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/text/CSourceViewerConfiguration.java
index fd83c63a055..7f0a8ca7f5f 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/text/CSourceViewerConfiguration.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/text/CSourceViewerConfiguration.java
@@ -531,6 +531,31 @@ public class CSourceViewerConfiguration extends TextSourceViewerConfiguration {
 	}
 
 	/**
+	 * Returns the configured indent width for this viewer.
+	 * @param sourceViewer
+	 * @return the indent width
+	 */
+	public int getIndentWidth(ISourceViewer sourceViewer) {
+		return CodeFormatterUtil.getIndentWidth(getProject());
+	}
+
+	/**
+	 * Returns whether spaces should be used exclusively for indentation.
+	 * 
+	 * @param sourceViewer
+	 * @return <code>true</code> if spaces should be used for indentation
+	 */
+	public boolean useSpacesOnly(ISourceViewer sourceViewer) {
+		ICProject project= getProject();
+		String option;
+		if (project == null)
+			option= CCorePlugin.getOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR);
+		else
+			option= project.getOption(DefaultCodeFormatterConstants.FORMATTER_TAB_CHAR, true);
+		return CCorePlugin.SPACE.equals(option);
+	}
+	
+	/**
 	 * @see SourceViewerConfiguration#getAnnotationHover(ISourceViewer)
 	 */
 	public IAnnotationHover getAnnotationHover(ISourceViewer sourceViewer) {
@@ -874,5 +899,4 @@ public class CSourceViewerConfiguration extends TextSourceViewerConfiguration {
         return conrolCreator;
     }
 
-
 }