bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/DirectoryProposalContentAssist.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2018 vogella GmbH and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     Fabian Pfaff <fabian.pfaff@vogella.com> - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.ide;

 import static java.util.stream.Collectors.toList;

 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.InvalidPathException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 import java.util.regex.Pattern;
 import java.util.stream.Stream;

 import org.eclipse.jface.bindings.keys.KeyStroke;
 import org.eclipse.jface.bindings.keys.ParseException;
 import org.eclipse.jface.fieldassist.ComboContentAdapter;
 import org.eclipse.jface.fieldassist.ContentProposal;
 import org.eclipse.jface.fieldassist.ContentProposalAdapter;
 import org.eclipse.jface.fieldassist.ControlDecoration;
 import org.eclipse.jface.fieldassist.FieldDecoration;
 import org.eclipse.jface.fieldassist.FieldDecorationRegistry;
 import org.eclipse.jface.fieldassist.IContentProposal;
 import org.eclipse.jface.fieldassist.IContentProposalListener2;
 import org.eclipse.jface.fieldassist.IContentProposalProvider;
 import org.eclipse.jface.fieldassist.IControlContentAdapter;
 import org.eclipse.osgi.util.NLS;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.KeyEvent;
 import org.eclipse.swt.events.KeyListener;
 import org.eclipse.swt.events.MouseListener;
 import org.eclipse.swt.widgets.Combo;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.ui.internal.WorkbenchMessages;

 /**
  * Adds content assist to a Combo, that is intended to be used to choose a
  * directory.
  */
 public class DirectoryProposalContentAssist {

 	private static class FileNameSubstringMatchContentProposalProvider implements IContentProposalProvider {

 		private List<String> proposals = Collections.emptyList();

 		/**
 		 * Returns an array of valid proposals filtered by substring matching of the
 		 * fileName.
 		 *
 		 * @param contents the current contents of the text field
 		 * @param position the current position of the cursor in the contents
 		 *
 		 * @return the array of {@link IContentProposal} that represent valid proposals
 		 *         for the field.
 		 */
 		@Override
 		public IContentProposal[] getProposals(String contents, int position) {
 			String substring = contents.substring(0, position);
 			// only match fileName as the folder part will be equal anyway and this makes
 			// substring matching easier
 			Pattern pattern = Pattern.compile(substring,
 					Pattern.LITERAL | Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
 			return proposals.stream()
 					.filter(proposal -> proposal.length() >= substring.length() && pattern.matcher(proposal).find())
 					.map(ContentProposal::new)
 					.toArray(IContentProposal[]::new);
 		}

 		/**
 		 * Set the Strings to be used as content proposals.
 		 *
 		 * @param proposals the Strings to be used as proposals.
 		 */
 		public void setProposals(List<String> proposals) {
 			this.proposals = proposals;
 		}

 	}

 	private static class OpenableContentProposalAdapter extends ContentProposalAdapter {

 		private static final String CONTENT_ASSIST_DECORATION_ID = "org.eclipse.ui.internal.ide.DirectoryProposalContentAssist$ReopenableContentProposalAdapter"; //$NON-NLS-1$

 		public OpenableContentProposalAdapter(Control control, IControlContentAdapter controlContentAdapter,
 				IContentProposalProvider proposalProvider, KeyStroke keyStroke, char[] autoActivationCharacters) {
 			super(control, controlContentAdapter, proposalProvider, keyStroke, autoActivationCharacters);
 			installContentProposalFieldDecoration(control, keyStroke);
 		}

 		/**
 		 * Installs a field decoration that shows the user that the control supports
 		 * content assist.
 		 *
 		 * @param control   the control that supports content assist
 		 * @param keyStroke the key stroke to be shown in the field decoration hover
 		 *                  text
 		 */
 		private void installContentProposalFieldDecoration(Control control, KeyStroke keyStroke) {
 			ControlDecoration decoration = new ControlDecoration(control, SWT.TOP | SWT.LEFT);
 			decoration.setShowOnlyOnFocus(true);
 			FieldDecoration dec = getContentAssistFieldDecoration(keyStroke);
 			decoration.setImage(dec.getImage());
 			decoration.setDescriptionText(dec.getDescription());
 		}

 		/**
 		 * Return the field decoration that should be used to indicate that content
 		 * assist is available for a field. Ensure that the decoration text includes the
 		 * correct key binding.
 		 *
 		 * @param keyStroke the key stroke to be shown in the hover text
 		 * @return the {@link FieldDecoration} that should be used to show content
 		 *         assist.
 		 **/
 		private FieldDecoration getContentAssistFieldDecoration(KeyStroke keyStroke) {
 			FieldDecorationRegistry registry = FieldDecorationRegistry.getDefault();
 			String decId = CONTENT_ASSIST_DECORATION_ID + keyStroke;
 			FieldDecoration dec = registry.getFieldDecoration(decId);

 			// If there is not one, base ours on the standard JFace one.
 			if (dec == null) {
 				FieldDecoration originalDec = registry.getFieldDecoration(FieldDecorationRegistry.DEC_CONTENT_PROPOSAL);

 				registry.registerFieldDecoration(decId, null, originalDec.getImage());
 				dec = registry.getFieldDecoration(decId);
 			}
 			dec.setDescription(NLS.bind(WorkbenchMessages.ContentAssist_Cue_Description_Key, keyStroke));
 			return dec;
 		}

 		@Override
 		public void openProposalPopup() {
 			super.openProposalPopup();
 		}

 	}

 	private class DirectoryProposalAutoCompleteField {

 		private FileNameSubstringMatchContentProposalProvider proposalProvider;
 		private OpenableContentProposalAdapter adapter;

 		public DirectoryProposalAutoCompleteField(Control control, IControlContentAdapter controlContentAdapter) {
 			proposalProvider = new FileNameSubstringMatchContentProposalProvider();
 			KeyStroke triggeringKeyStroke = safeKeyStroke("Ctrl+Space"); //$NON-NLS-1$
 			String backspace = "\b"; //$NON-NLS-1$
 			String delete = "\u007F"; //$NON-NLS-1$
 			char[] autoactivationChars = ("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789" + backspace //$NON-NLS-1$
 					+ delete).toCharArray();
 			adapter = new OpenableContentProposalAdapter(control, controlContentAdapter, proposalProvider,
 					triggeringKeyStroke, autoactivationChars);
 			adapter.setPropagateKeys(true);
 			adapter.setProposalAcceptanceStyle(ContentProposalAdapter.PROPOSAL_REPLACE);
 		}

 		private KeyStroke safeKeyStroke(String keyStrokePattern) {
 			try {
 				return KeyStroke.getInstance(keyStrokePattern);
 			} catch (ParseException e) {
 				return null;
 			}
 		}

 		/**
 		 * Sets the given proposals on the content provider and forces the proposal
 		 * pop-up to refresh its content.
 		 *
 		 * @param proposals         the proposals to set
 		 * @param openProposalPopup if the proposal pop-up should be opened
 		 */
 		public void refreshProposals(List<String> proposals, boolean openProposalPopup) {
 			proposalProvider.setProposals(proposals);
 			adapter.refresh();
 			if (openProposalPopup) {
 				adapter.openProposalPopup();
 			}
 		}

 	}

 	private Path lastDir;
 	private DirectoryProposalAutoCompleteField autoCompleteField;
 	private Combo directoryCombo;
 	/**
 	 * The {@link ContentProposalAdapter} closes the proposal pop-up when the
 	 * proposals are empty. This remembers the popup state and reopen the popup
 	 * after the proposals have been updated by the asynchronous job.
 	 */
 	private boolean popupActivated = false;
 	private List<CompletableFuture<Void>> proposalUpdateFutures = Collections.synchronizedList(new ArrayList<>());

 	/**
 	 * Applies auto-completion to a Combo that is intended to be used to choose a
 	 * directory. Proposals are triggered automatically, but can also be triggered
 	 * by pressing Ctrl+Space.
 	 *
 	 * @param combo the Combo that gets the auto-completion applied
 	 */
 	public void apply(Combo combo) {
 		directoryCombo = combo;
 		autoCompleteField = new DirectoryProposalAutoCompleteField(directoryCombo, new ComboContentAdapter());

 		getContentProposalAdapter().addContentProposalListener(e -> updateProposals(directoryCombo.getText(), false));
 		getContentProposalAdapter().addContentProposalListener(new IContentProposalListener2() {

 			@Override
 			public void proposalPopupOpened(ContentProposalAdapter adapter) {
 				popupActivated = true;
 			}

 			@Override
 			public void proposalPopupClosed(ContentProposalAdapter adapter) {
 				// do nothing on purpose
 			}
 		});

 		directoryCombo.addModifyListener(
 				e -> updateProposals(directoryCombo.getText().substring(0, directoryCombo.getCaretPosition()), true));

 		directoryCombo.addKeyListener(KeyListener.keyPressedAdapter(e -> {
 			if (e.keyCode == SWT.ESC) {
 				popupActivated = false;
 			}
 		}));
 		// use key release because otherwise the caret position is not yet updated
 		directoryCombo.addKeyListener(KeyListener.keyReleasedAdapter(e -> {
 			if (isTraverse(e)) {
 				int caretPosition = directoryCombo.getCaretPosition();
 				updateProposals(directoryCombo.getText().substring(0, caretPosition), popupActivated);
 			}
 		}));

 		directoryCombo.addMouseListener(MouseListener.mouseUpAdapter(e -> {
 			int caretPosition = ((Combo) e.getSource()).getCaretPosition();
 			updateProposals(directoryCombo.getText().substring(0, caretPosition), false);
 		}));
 	}

 	private boolean isTraverse(KeyEvent e) {
 		return e.keyCode == SWT.ARROW_LEFT || e.keyCode == SWT.ARROW_RIGHT
 				 || e.keyCode == SWT.HOME || e.keyCode == SWT.END;
 	}

 	/**
 	 * Checks if the directory in the combo has changed. If the directory has
 	 * changed the proposals get asynchronously updated with the subfolders of the
 	 * new directory. If the current content of the combo is not a valid directory
 	 * the proposals get cleared.
 	 */
 	private void updateProposals(String textFromCombo, boolean openProposalPopup) {
 		Path dir = pathWithoutFileName(textFromCombo);
 		if (dir != null && dir.equals(lastDir)) {
 			if (openProposalPopup) {
 				autoCompleteField.adapter.openProposalPopup();
 			}
 			return;
 		}
 		if (dir == null || !safeIsDirectory(dir)) {
 			updateProposals(Collections.emptyList(), false);
 			lastDir = null;
 			return;
 		}

 		lastDir = dir;

 		CompletableFuture<Void> completableFuture = CompletableFuture
 				.runAsync(() -> updateProposals(retrieveDirectoriesIn(dir), openProposalPopup));

 		proposalUpdateFutures.add(completableFuture);
 		proposalUpdateFutures.removeIf(CompletableFuture::isDone);
 	}

 	private List<String> retrieveDirectoriesIn(Path dir) {
 		try (Stream<Path> files = Files.list(dir)) {
 			return filterPaths(files).sorted().collect(toList());
 		} catch (IOException ex) {
 			return new ArrayList<>();
 		}
 	}

 	private void updateProposals(List<String> proposals, boolean openProposalPopup) {
 		directoryCombo.getDisplay().syncExec(() -> autoCompleteField.refreshProposals(proposals, openProposalPopup));
 	}

 	private Path pathWithoutFileName(String inputPath) {
 		int lastIndex = inputPath.lastIndexOf(File.separatorChar);
 		if (separatorNotFound(lastIndex)) {
 			return null;
 		}
 		return safeGetPath(removeFileName(inputPath, lastIndex));
 	}

 	private boolean separatorNotFound(int lastIndex) {
 		return lastIndex < 0;
 	}

 	private String removeFileName(String text, int lastIndex) {
 		if (lastIndex == 0) {
 			return File.separator;
 		}
 		return text.substring(0, lastIndex + 1);
 	}

 	private Path safeGetPath(String text) {
 		try {
 			return Paths.get(text);
 		} catch (InvalidPathException ex) {
 			return null;
 		}
 	}

 	private boolean safeIsDirectory(Path dir) {
 		try {
 			return dir.toFile().isDirectory();
 		} catch (SecurityException ex) {
 			return false;
 		}
 	}

 	/**
 	 * Filters out files and hidden directories.
 	 *
 	 * @param paths the Paths to filter
 	 * @return the filtered paths
 	 */
 	private Stream<String> filterPaths(Stream<Path> paths) {
 		return paths.filter(path -> {
 			try {
 				return safeIsDirectory(path) && !Files.isHidden(path);
 			} catch (IOException e) {
 				return false;
 			}
 		}).map(path -> path.toString() + File.separator);
 	}

 	public DirectoryProposalAutoCompleteField getAutoCompleteField() {
 		return autoCompleteField;
 	}

 	public ContentProposalAdapter getContentProposalAdapter() {
 		return autoCompleteField.adapter;
 	}

 	/**
 	 * Wait until the asynchronous proposal refresh is finished. This method is
 	 * intended to by used by tests.
 	 *
 	 * @param timeout timeout in milliseconds
 	 * @throws TimeoutException     if the wait timed out
 	 * @throws ExecutionException   if the future completed exceptionally
 	 * @throws InterruptedException if the current thread was interrupted while
 	 *                              waiting
 	 */
 	protected void wait(int timeout) throws InterruptedException, ExecutionException, TimeoutException {
 		CompletableFuture.allOf(proposalUpdateFutures.toArray(new CompletableFuture[proposalUpdateFutures.size()]))
 				.get(timeout, TimeUnit.MILLISECONDS);
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2018 vogella GmbH and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* Fabian Pfaff <fabian.pfaff@vogella.com> - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ui.internal.ide;

	import static java.util.stream.Collectors.toList;

	import java.io.File;
	import java.io.IOException;
	import java.nio.file.Files;
	import java.nio.file.InvalidPathException;
	import java.nio.file.Path;
	import java.nio.file.Paths;
	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.List;
	import java.util.concurrent.CompletableFuture;
	import java.util.concurrent.ExecutionException;
	import java.util.concurrent.TimeUnit;
	import java.util.concurrent.TimeoutException;
	import java.util.regex.Pattern;
	import java.util.stream.Stream;

	import org.eclipse.jface.bindings.keys.KeyStroke;
	import org.eclipse.jface.bindings.keys.ParseException;
	import org.eclipse.jface.fieldassist.ComboContentAdapter;
	import org.eclipse.jface.fieldassist.ContentProposal;
	import org.eclipse.jface.fieldassist.ContentProposalAdapter;
	import org.eclipse.jface.fieldassist.ControlDecoration;
	import org.eclipse.jface.fieldassist.FieldDecoration;
	import org.eclipse.jface.fieldassist.FieldDecorationRegistry;
	import org.eclipse.jface.fieldassist.IContentProposal;
	import org.eclipse.jface.fieldassist.IContentProposalListener2;
	import org.eclipse.jface.fieldassist.IContentProposalProvider;
	import org.eclipse.jface.fieldassist.IControlContentAdapter;
	import org.eclipse.osgi.util.NLS;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.KeyEvent;
	import org.eclipse.swt.events.KeyListener;
	import org.eclipse.swt.events.MouseListener;
	import org.eclipse.swt.widgets.Combo;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.ui.internal.WorkbenchMessages;

	/**
	* Adds content assist to a Combo, that is intended to be used to choose a
	* directory.
	*/
	public class DirectoryProposalContentAssist {

	private static class FileNameSubstringMatchContentProposalProvider implements IContentProposalProvider {

	private List<String> proposals = Collections.emptyList();

	/**
	* Returns an array of valid proposals filtered by substring matching of the
	* fileName.
	*
	* @param contents the current contents of the text field
	* @param position the current position of the cursor in the contents
	*
	* @return the array of {@link IContentProposal} that represent valid proposals
	* for the field.
	*/
	@Override
	public IContentProposal[] getProposals(String contents, int position) {
	String substring = contents.substring(0, position);
	// only match fileName as the folder part will be equal anyway and this makes
	// substring matching easier
	Pattern pattern = Pattern.compile(substring,
	Pattern.LITERAL \| Pattern.CASE_INSENSITIVE \| Pattern.UNICODE_CASE);
	return proposals.stream()
	.filter(proposal -> proposal.length() >= substring.length() && pattern.matcher(proposal).find())
	.map(ContentProposal::new)
	.toArray(IContentProposal[]::new);
	}

	/**
	* Set the Strings to be used as content proposals.
	*
	* @param proposals the Strings to be used as proposals.
	*/
	public void setProposals(List<String> proposals) {
	this.proposals = proposals;
	}

	}

	private static class OpenableContentProposalAdapter extends ContentProposalAdapter {

	private static final String CONTENT_ASSIST_DECORATION_ID = "org.eclipse.ui.internal.ide.DirectoryProposalContentAssist$ReopenableContentProposalAdapter"; //$NON-NLS-1$

	public OpenableContentProposalAdapter(Control control, IControlContentAdapter controlContentAdapter,
	IContentProposalProvider proposalProvider, KeyStroke keyStroke, char[] autoActivationCharacters) {
	super(control, controlContentAdapter, proposalProvider, keyStroke, autoActivationCharacters);
	installContentProposalFieldDecoration(control, keyStroke);
	}

	/**
	* Installs a field decoration that shows the user that the control supports
	* content assist.
	*
	* @param control the control that supports content assist
	* @param keyStroke the key stroke to be shown in the field decoration hover
	* text
	*/
	private void installContentProposalFieldDecoration(Control control, KeyStroke keyStroke) {
	ControlDecoration decoration = new ControlDecoration(control, SWT.TOP \| SWT.LEFT);
	decoration.setShowOnlyOnFocus(true);
	FieldDecoration dec = getContentAssistFieldDecoration(keyStroke);
	decoration.setImage(dec.getImage());
	decoration.setDescriptionText(dec.getDescription());
	}

	/**
	* Return the field decoration that should be used to indicate that content
	* assist is available for a field. Ensure that the decoration text includes the
	* correct key binding.
	*
	* @param keyStroke the key stroke to be shown in the hover text
	* @return the {@link FieldDecoration} that should be used to show content
	* assist.
	**/
	private FieldDecoration getContentAssistFieldDecoration(KeyStroke keyStroke) {
	FieldDecorationRegistry registry = FieldDecorationRegistry.getDefault();
	String decId = CONTENT_ASSIST_DECORATION_ID + keyStroke;
	FieldDecoration dec = registry.getFieldDecoration(decId);

	// If there is not one, base ours on the standard JFace one.
	if (dec == null) {
	FieldDecoration originalDec = registry.getFieldDecoration(FieldDecorationRegistry.DEC_CONTENT_PROPOSAL);

	registry.registerFieldDecoration(decId, null, originalDec.getImage());
	dec = registry.getFieldDecoration(decId);
	}
	dec.setDescription(NLS.bind(WorkbenchMessages.ContentAssist_Cue_Description_Key, keyStroke));
	return dec;
	}

	@Override
	public void openProposalPopup() {
	super.openProposalPopup();
	}

	}

	private class DirectoryProposalAutoCompleteField {

	private FileNameSubstringMatchContentProposalProvider proposalProvider;
	private OpenableContentProposalAdapter adapter;

	public DirectoryProposalAutoCompleteField(Control control, IControlContentAdapter controlContentAdapter) {
	proposalProvider = new FileNameSubstringMatchContentProposalProvider();
	KeyStroke triggeringKeyStroke = safeKeyStroke("Ctrl+Space"); //$NON-NLS-1$
	String backspace = "\b"; //$NON-NLS-1$
	String delete = "\u007F"; //$NON-NLS-1$
	char[] autoactivationChars = ("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789" + backspace //$NON-NLS-1$
	+ delete).toCharArray();
	adapter = new OpenableContentProposalAdapter(control, controlContentAdapter, proposalProvider,
	triggeringKeyStroke, autoactivationChars);
	adapter.setPropagateKeys(true);
	adapter.setProposalAcceptanceStyle(ContentProposalAdapter.PROPOSAL_REPLACE);
	}

	private KeyStroke safeKeyStroke(String keyStrokePattern) {
	try {
	return KeyStroke.getInstance(keyStrokePattern);
	} catch (ParseException e) {
	return null;
	}
	}

	/**
	* Sets the given proposals on the content provider and forces the proposal
	* pop-up to refresh its content.
	*
	* @param proposals the proposals to set
	* @param openProposalPopup if the proposal pop-up should be opened
	*/
	public void refreshProposals(List<String> proposals, boolean openProposalPopup) {
	proposalProvider.setProposals(proposals);
	adapter.refresh();
	if (openProposalPopup) {
	adapter.openProposalPopup();
	}
	}

	}

	private Path lastDir;
	private DirectoryProposalAutoCompleteField autoCompleteField;
	private Combo directoryCombo;
	/**
	* The {@link ContentProposalAdapter} closes the proposal pop-up when the
	* proposals are empty. This remembers the popup state and reopen the popup
	* after the proposals have been updated by the asynchronous job.
	*/
	private boolean popupActivated = false;
	private List<CompletableFuture<Void>> proposalUpdateFutures = Collections.synchronizedList(new ArrayList<>());

	/**
	* Applies auto-completion to a Combo that is intended to be used to choose a
	* directory. Proposals are triggered automatically, but can also be triggered
	* by pressing Ctrl+Space.
	*
	* @param combo the Combo that gets the auto-completion applied
	*/
	public void apply(Combo combo) {
	directoryCombo = combo;
	autoCompleteField = new DirectoryProposalAutoCompleteField(directoryCombo, new ComboContentAdapter());

	getContentProposalAdapter().addContentProposalListener(e -> updateProposals(directoryCombo.getText(), false));
	getContentProposalAdapter().addContentProposalListener(new IContentProposalListener2() {

	@Override
	public void proposalPopupOpened(ContentProposalAdapter adapter) {
	popupActivated = true;
	}

	@Override
	public void proposalPopupClosed(ContentProposalAdapter adapter) {
	// do nothing on purpose
	}
	});

	directoryCombo.addModifyListener(
	e -> updateProposals(directoryCombo.getText().substring(0, directoryCombo.getCaretPosition()), true));

	directoryCombo.addKeyListener(KeyListener.keyPressedAdapter(e -> {
	if (e.keyCode == SWT.ESC) {
	popupActivated = false;
	}
	}));
	// use key release because otherwise the caret position is not yet updated
	directoryCombo.addKeyListener(KeyListener.keyReleasedAdapter(e -> {
	if (isTraverse(e)) {
	int caretPosition = directoryCombo.getCaretPosition();
	updateProposals(directoryCombo.getText().substring(0, caretPosition), popupActivated);
	}
	}));

	directoryCombo.addMouseListener(MouseListener.mouseUpAdapter(e -> {
	int caretPosition = ((Combo) e.getSource()).getCaretPosition();
	updateProposals(directoryCombo.getText().substring(0, caretPosition), false);
	}));
	}

	private boolean isTraverse(KeyEvent e) {
	return e.keyCode == SWT.ARROW_LEFT \|\| e.keyCode == SWT.ARROW_RIGHT
	\|\| e.keyCode == SWT.HOME \|\| e.keyCode == SWT.END;
	}

	/**
	* Checks if the directory in the combo has changed. If the directory has
	* changed the proposals get asynchronously updated with the subfolders of the
	* new directory. If the current content of the combo is not a valid directory
	* the proposals get cleared.
	*/
	private void updateProposals(String textFromCombo, boolean openProposalPopup) {
	Path dir = pathWithoutFileName(textFromCombo);
	if (dir != null && dir.equals(lastDir)) {
	if (openProposalPopup) {
	autoCompleteField.adapter.openProposalPopup();
	}
	return;
	}
	if (dir == null \|\| !safeIsDirectory(dir)) {
	updateProposals(Collections.emptyList(), false);
	lastDir = null;
	return;
	}

	lastDir = dir;

	CompletableFuture<Void> completableFuture = CompletableFuture
	.runAsync(() -> updateProposals(retrieveDirectoriesIn(dir), openProposalPopup));

	proposalUpdateFutures.add(completableFuture);
	proposalUpdateFutures.removeIf(CompletableFuture::isDone);
	}

	private List<String> retrieveDirectoriesIn(Path dir) {
	try (Stream<Path> files = Files.list(dir)) {
	return filterPaths(files).sorted().collect(toList());
	} catch (IOException ex) {
	return new ArrayList<>();
	}
	}

	private void updateProposals(List<String> proposals, boolean openProposalPopup) {
	directoryCombo.getDisplay().syncExec(() -> autoCompleteField.refreshProposals(proposals, openProposalPopup));
	}

	private Path pathWithoutFileName(String inputPath) {
	int lastIndex = inputPath.lastIndexOf(File.separatorChar);
	if (separatorNotFound(lastIndex)) {
	return null;
	}
	return safeGetPath(removeFileName(inputPath, lastIndex));
	}

	private boolean separatorNotFound(int lastIndex) {
	return lastIndex < 0;
	}

	private String removeFileName(String text, int lastIndex) {
	if (lastIndex == 0) {
	return File.separator;
	}
	return text.substring(0, lastIndex + 1);
	}

	private Path safeGetPath(String text) {
	try {
	return Paths.get(text);
	} catch (InvalidPathException ex) {
	return null;
	}
	}

	private boolean safeIsDirectory(Path dir) {
	try {
	return dir.toFile().isDirectory();
	} catch (SecurityException ex) {
	return false;
	}
	}

	/**
	* Filters out files and hidden directories.
	*
	* @param paths the Paths to filter
	* @return the filtered paths
	*/
	private Stream<String> filterPaths(Stream<Path> paths) {
	return paths.filter(path -> {
	try {
	return safeIsDirectory(path) && !Files.isHidden(path);
	} catch (IOException e) {
	return false;
	}
	}).map(path -> path.toString() + File.separator);
	}

	public DirectoryProposalAutoCompleteField getAutoCompleteField() {
	return autoCompleteField;
	}

	public ContentProposalAdapter getContentProposalAdapter() {
	return autoCompleteField.adapter;
	}

	/**
	* Wait until the asynchronous proposal refresh is finished. This method is
	* intended to by used by tests.
	*
	* @param timeout timeout in milliseconds
	* @throws TimeoutException if the wait timed out
	* @throws ExecutionException if the future completed exceptionally
	* @throws InterruptedException if the current thread was interrupted while
	* waiting
	*/
	protected void wait(int timeout) throws InterruptedException, ExecutionException, TimeoutException {
	CompletableFuture.allOf(proposalUpdateFutures.toArray(new CompletableFuture[proposalUpdateFutures.size()]))
	.get(timeout, TimeUnit.MILLISECONDS);
	}

	}