bug 379165: [sd90] Reindex using accurate list of affected resources

after LSE change event

core/org.eclipse.cdt.core.tests/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsListenersTests.java

@@ -13,6 +13,7 @@ package org.eclipse.cdt.core.language.settings.providers;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Set;
 
 import junit.framework.TestSuite;
 
@@ -25,7 +26,10 @@ import org.eclipse.cdt.core.testplugin.ResourceHelper;
 import org.eclipse.cdt.core.testplugin.util.BaseTestCase;
 import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsProvidersSerializer;
 import org.eclipse.cdt.internal.core.settings.model.CProjectDescriptionManager;
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.resources.IFolder;
 import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IResource;
 import org.eclipse.core.runtime.jobs.Job;
 
 /**
@@ -1131,5 +1135,371 @@ public class LanguageSettingsListenersTests extends BaseTestCase {
 			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
 		}
 	}
+
+	/**
+	 * Test case when a project is present in the list of resources in delta.
+	 */
+	public void testDelta_AffectedResources_Project() throws Exception {
+		// create project
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		ScannerDiscoveryLegacySupport.setLanguageSettingsProvidersFunctionalityEnabled(project, true);
+
+		// create a mock provider and add to cfgDescription
+		{
+			// get project descriptions
+			ICProjectDescription prjDescriptionWritable = CProjectDescriptionManager.getInstance().getProjectDescription(project, true);
+			assertNotNull(prjDescriptionWritable);
+			ICConfigurationDescription[] cfgDescriptions = prjDescriptionWritable.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+
+			// add mock provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			MockLanguageSettingsEditableProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			providers.add(mockProvider);
+			((ILanguageSettingsProvidersKeeper) cfgDescription).setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = ((ILanguageSettingsProvidersKeeper) cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, prjDescriptionWritable);
+		}
+
+		// register mock listener to inspect the notifications
+		{
+			LanguageSettingsManager.registerLanguageSettingsChangeListener(mockLseListener);
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+		}
+
+		// trigger an event on the project
+		ICConfigurationDescription cfgDescription;
+		{
+			// get project descriptions
+			ICProjectDescription prjDescription = CProjectDescriptionManager.getInstance().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+			List<ILanguageSettingsProvider> providers = ((ILanguageSettingsProvidersKeeper)cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			mockProvider.setSettingEntries(cfgDescription, project, null, entries);
+			mockProvider.serializeLanguageSettings(cfgDescription);
+		}
+
+		// inspect event
+		{
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			assertEquals(event.getProjectName(), project.getName());
+
+			Set<IResource> resources = event.getAffectedResources(cfgDescription.getId());
+			assertNotNull(resources);
+			assertEquals(project, resources.toArray()[0]);
+			assertEquals(1, resources.size());
+		}
+	}
+
+	/**
+	 * Test case when a default resource (null) is represented in the list of resources in delta.
+	 */
+	public void testDelta_AffectedResources_DefaultResource() throws Exception {
+		// create project
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		ScannerDiscoveryLegacySupport.setLanguageSettingsProvidersFunctionalityEnabled(project, true);
+
+		// create a mock provider and add to cfgDescription
+		{
+			// get project descriptions
+			ICProjectDescription prjDescriptionWritable = CProjectDescriptionManager.getInstance().getProjectDescription(project, true);
+			assertNotNull(prjDescriptionWritable);
+			ICConfigurationDescription[] cfgDescriptions = prjDescriptionWritable.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+
+			// add mock provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			MockLanguageSettingsEditableProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			providers.add(mockProvider);
+			((ILanguageSettingsProvidersKeeper) cfgDescription).setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = ((ILanguageSettingsProvidersKeeper) cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, prjDescriptionWritable);
+		}
+
+		// register mock listener to inspect the notifications
+		{
+			LanguageSettingsManager.registerLanguageSettingsChangeListener(mockLseListener);
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+		}
+
+		// trigger an event on the project
+		ICConfigurationDescription cfgDescription;
+		{
+			// get project descriptions
+			ICProjectDescription prjDescription = CProjectDescriptionManager.getInstance().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+			List<ILanguageSettingsProvider> providers = ((ILanguageSettingsProvidersKeeper)cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			mockProvider.setSettingEntries(cfgDescription, null, null, entries);
+			mockProvider.serializeLanguageSettings(cfgDescription);
+		}
+
+		// inspect event
+		{
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			assertEquals(event.getProjectName(), project.getName());
+
+			Set<IResource> resources = event.getAffectedResources(cfgDescription.getId());
+			assertNotNull(resources);
+			assertEquals(project, resources.toArray()[0]);
+			assertEquals(1, resources.size());
+		}
+	}
+
+	/**
+	 * Test case when a folder is present in the list of resources in delta.
+	 */
+	public void testDelta_AffectedResources_Folder() throws Exception {
+		// create project
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		IFolder folder = ResourceHelper.createFolder(project, "Folder");
+		ScannerDiscoveryLegacySupport.setLanguageSettingsProvidersFunctionalityEnabled(project, true);
+
+		// create a mock provider and add to cfgDescription
+		{
+			// get project descriptions
+			ICProjectDescription prjDescriptionWritable = CProjectDescriptionManager.getInstance().getProjectDescription(project, true);
+			assertNotNull(prjDescriptionWritable);
+			ICConfigurationDescription[] cfgDescriptions = prjDescriptionWritable.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+
+			// add mock provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			MockLanguageSettingsEditableProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			providers.add(mockProvider);
+			((ILanguageSettingsProvidersKeeper) cfgDescription).setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = ((ILanguageSettingsProvidersKeeper) cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, prjDescriptionWritable);
+		}
+
+		// register mock listener to inspect the notifications
+		{
+			LanguageSettingsManager.registerLanguageSettingsChangeListener(mockLseListener);
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+		}
+
+		// trigger an event on the project
+		ICConfigurationDescription cfgDescription;
+		{
+			// get project descriptions
+			ICProjectDescription prjDescription = CProjectDescriptionManager.getInstance().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+			List<ILanguageSettingsProvider> providers = ((ILanguageSettingsProvidersKeeper)cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			mockProvider.setSettingEntries(cfgDescription, folder, null, entries);
+			mockProvider.serializeLanguageSettings(cfgDescription);
+		}
+
+		// inspect event
+		{
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			assertEquals(event.getProjectName(), project.getName());
+
+			Set<IResource> resources = event.getAffectedResources(cfgDescription.getId());
+			assertNotNull(resources);
+			assertEquals(folder, resources.toArray()[0]);
+			assertEquals(1, resources.size());
+		}
+	}
+
+	/**
+	 * Test case when a file is present in the list of resources in delta.
+	 */
+	public void testDelta_AffectedResources_File() throws Exception {
+		// create project
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		IFile file = ResourceHelper.createFile(project, "file.cpp");
+		ScannerDiscoveryLegacySupport.setLanguageSettingsProvidersFunctionalityEnabled(project, true);
+
+		// create a mock provider and add to cfgDescription
+		{
+			// get project descriptions
+			ICProjectDescription prjDescriptionWritable = CProjectDescriptionManager.getInstance().getProjectDescription(project, true);
+			assertNotNull(prjDescriptionWritable);
+			ICConfigurationDescription[] cfgDescriptions = prjDescriptionWritable.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+
+			// add mock provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			MockLanguageSettingsEditableProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			providers.add(mockProvider);
+			((ILanguageSettingsProvidersKeeper) cfgDescription).setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = ((ILanguageSettingsProvidersKeeper) cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, prjDescriptionWritable);
+		}
+
+		// register mock listener to inspect the notifications
+		{
+			LanguageSettingsManager.registerLanguageSettingsChangeListener(mockLseListener);
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+		}
+
+		// trigger an event on the project
+		ICConfigurationDescription cfgDescription;
+		{
+			// get project descriptions
+			ICProjectDescription prjDescription = CProjectDescriptionManager.getInstance().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+			List<ILanguageSettingsProvider> providers = ((ILanguageSettingsProvidersKeeper)cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			mockProvider.setSettingEntries(cfgDescription, file, null, entries);
+			mockProvider.serializeLanguageSettings(cfgDescription);
+		}
+
+		// inspect event
+		{
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			assertEquals(event.getProjectName(), project.getName());
+
+			Set<IResource> resources = event.getAffectedResources(cfgDescription.getId());
+			assertNotNull(resources);
+			assertEquals(file, resources.toArray()[0]);
+			assertEquals(1, resources.size());
+		}
+	}
+
+	/**
+	 * Test case when a mix of files and folders is present in the list of resources in delta.
+	 */
+	public void testDelta_AffectedResources_Mix() throws Exception {
+		// create project
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		IFolder folder = ResourceHelper.createFolder(project, "Folder");
+		IFile file1 = ResourceHelper.createFile(project, "file1.cpp");
+		IFile file2 = ResourceHelper.createFile(project, "file2.cpp");
+		IFile file3 = ResourceHelper.createFile(project, "file3.cpp");
+		ScannerDiscoveryLegacySupport.setLanguageSettingsProvidersFunctionalityEnabled(project, true);
+
+		// create a mock provider and add to cfgDescription
+		{
+			// get project descriptions
+			ICProjectDescription prjDescriptionWritable = CProjectDescriptionManager.getInstance().getProjectDescription(project, true);
+			assertNotNull(prjDescriptionWritable);
+			ICConfigurationDescription[] cfgDescriptions = prjDescriptionWritable.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+
+			// add mock provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			MockLanguageSettingsEditableProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			providers.add(mockProvider);
+			((ILanguageSettingsProvidersKeeper) cfgDescription).setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = ((ILanguageSettingsProvidersKeeper) cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, prjDescriptionWritable);
+		}
+
+		// register mock listener to inspect the notifications
+		{
+			LanguageSettingsManager.registerLanguageSettingsChangeListener(mockLseListener);
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+		}
+
+		// trigger an event on the project
+		ICConfigurationDescription cfgDescription;
+		{
+			// get project descriptions
+			ICProjectDescription prjDescription = CProjectDescriptionManager.getInstance().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			cfgDescription = cfgDescriptions[0];
+			assertTrue(cfgDescription instanceof ILanguageSettingsProvidersKeeper);
+			List<ILanguageSettingsProvider> providers = ((ILanguageSettingsProvidersKeeper)cfgDescription).getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			mockProvider.setSettingEntries(cfgDescription, folder, null, entries);
+			mockProvider.setSettingEntries(cfgDescription, file1, null, entries);
+			mockProvider.setSettingEntries(cfgDescription, file2, null, entries);
+			mockProvider.serializeLanguageSettings(cfgDescription);
+		}
+
+		// inspect event
+		{
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			assertEquals(event.getProjectName(), project.getName());
+
+			Set<IResource> resources = event.getAffectedResources(cfgDescription.getId());
+			assertNotNull(resources);
+			assertTrue(resources.contains(folder));
+			assertTrue(resources.contains(file1));
+			assertTrue(resources.contains(file2));
+			assertFalse(resources.contains(file3));
+			assertEquals(3, resources.size());
+		}
+	}
 }
 

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/language/settings/providers/ILanguageSettingsChangeEvent.java

@@ -10,7 +10,10 @@
  *******************************************************************************/
 package org.eclipse.cdt.core.language.settings.providers;
 
+import java.util.Set;
+
 import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
+import org.eclipse.core.resources.IResource;
 
 /**
  * Contains the details of changes that occurred as a result of modifying
@@ -21,7 +24,7 @@ import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
  * <p>
  * <strong>EXPERIMENTAL</strong>. This class interface is not stable yet as
  * it is not currently clear how it may need to be used in future. Only bare
- * minimum is provided here at this point (CDT 9.0, Juno).
+ * minimum is provided here at this point (CDT 8.1, Juno).
  * There is no guarantee that this API will work or that it will remain the same.
  * Please do not use this API without consulting with the CDT team.
  * </p>
@@ -38,8 +41,12 @@ public interface ILanguageSettingsChangeEvent {
 	public String getProjectName();
 
 	/**
-	 * @return configuration IDs which are affected by the language settings changes.
+	 * @return configuration IDs which are affected by the language settings entries changes.
 	 */
 	public String[] getConfigurationDescriptionIds();
 
+	/**
+	 * @return list of resources affected by the language settings entries changes.
+	 */
+	public Set<IResource> getAffectedResources(String cfgId);
 }

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsStorage.java

@@ -14,6 +14,7 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -91,8 +92,10 @@ public class LanguageSettingsStorage implements Cloneable {
 	/**
 	 * Sets language settings entries for the resource and language.
 	 *
-	 * @param rcProjectPath - path to the resource relative to the project.
-	 * @param languageId - language id.
+	 * @param rcProjectPath - path to the resource relative to the project. If {@code null} the entries are
+	 *    considered to be being defined as default entries for resources.
+	 * @param languageId - language id. If {@code null}, then entries are considered
+	 *    to be defined for the language scope.
 	 * @param entries - language settings entries to set.
 	 */
 	public void setSettingEntries(String rcProjectPath, String languageId, List<ICLanguageSettingEntry> entries) {
@@ -134,6 +137,31 @@ public class LanguageSettingsStorage implements Cloneable {
 		}
 	}
 
+	/**
+	 * @return set of all languages associated with the entries.
+	 * Note that the storage can keep default entries for the language scope
+	 * of the provider, so the set can contain {@code null}.
+	 */
+	public Set<String> getLanguages() {
+		return new HashSet<String>(fStorage.keySet());
+	}
+
+	/**
+	 * Returns set of paths for all resources associated with entries for given language.
+	 * The paths are project relative.
+	 *
+	 * @param languageId - language ID.
+	 * @return the set of resource paths associated with entries for the given language or empty set.
+	 * Note that the storage can keep default entries for resources, so the set can contain {@code null}.
+	 */
+	public Set<String> getResourcePaths(String languageId) {
+		Map<String, List<ICLanguageSettingEntry>> rcPathsMap = fStorage.get(languageId);
+		if (rcPathsMap == null) {
+			return new HashSet<String>();
+		}
+		return new HashSet<String>(rcPathsMap.keySet());
+	}
+
 	/**
 	 * Find and return the equal list of entries from the pool.
 	 *

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsDelta.java

@@ -11,6 +11,9 @@
 package org.eclipse.cdt.internal.core.language.settings.providers;
 
 import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
 
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsStorage;
 import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
@@ -24,7 +27,7 @@ import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
  * <p>
  * <strong>EXPERIMENTAL</strong>. This class interface is not stable yet as
  * it is not currently clear how it may need to be used in future. Only bare
- * minimum is provided here at this point (CDT 9.0, Juno).
+ * minimum is provided here at this point (CDT 8.1, Juno).
  * There is no guarantee that this API will work or that it will remain the same.
  * Please do not use this API without consulting with the CDT team.
  * </p>
@@ -33,12 +36,12 @@ import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
  * @noinstantiate This class is not intended to be instantiated by clients.
  */
 public class LanguageSettingsDelta {
-	// maps need to be ordered by providers
-	@SuppressWarnings("unused")
+	// maps are ordered by providers
 	private LinkedHashMap<String/*providerId*/, LanguageSettingsStorage> oldLanguageSettingsState;
-	@SuppressWarnings("unused")
 	private LinkedHashMap<String/*providerId*/, LanguageSettingsStorage> newLanguageSettingsState;
 
+	private Set<String> paths = null;
+
 	/**
 	 * Constructor.
 	 *
@@ -50,4 +53,64 @@ public class LanguageSettingsDelta {
 		newLanguageSettingsState = newState;
 	}
 
+	/**
+	 * @return resource paths affected by changes represented by this delta.
+	 */
+	public Set<String> getAffectedResourcePaths() {
+		if (paths != null) {
+			return paths;
+		}
+
+		paths = new TreeSet<String>();
+
+		LanguageSettingsStorage oldCombinedStorage = combineStorage(oldLanguageSettingsState);
+		LanguageSettingsStorage newCombinedStorage = combineStorage(newLanguageSettingsState);
+
+		for (String lang : oldCombinedStorage.getLanguages()) {
+			for (String path : oldCombinedStorage.getResourcePaths(lang)) {
+				if (oldCombinedStorage.getSettingEntries(path, lang) != newCombinedStorage.getSettingEntries(path, lang)) {
+					if (path == null) {
+						// add path of the project
+						path = ""; //$NON-NLS-1$
+					}
+					paths.add(path);
+				}
+			}
+		}
+
+		for (String lang : newCombinedStorage.getLanguages()) {
+			for (String path : newCombinedStorage.getResourcePaths(lang)) {
+				if (newCombinedStorage.getSettingEntries(path, lang) != oldCombinedStorage.getSettingEntries(path, lang)) {
+					if (path == null) {
+						// add path of the project
+						path = ""; //$NON-NLS-1$
+					}
+					paths.add(path);
+				}
+			}
+		}
+
+		return paths;
+	}
+
+	/**
+	 * Language settings entries from different providers can overlap. This method resolves all overlapping
+	 * ones combining entries into one aggregate storage.
+	 */
+	private LanguageSettingsStorage combineStorage(LinkedHashMap<String, LanguageSettingsStorage> state) {
+		LanguageSettingsStorage combinedStore = new LanguageSettingsStorage();
+		for (LanguageSettingsStorage providerStore : state.values()) {
+			for (String lang : providerStore.getLanguages()) {
+				for (String path : providerStore.getResourcePaths(lang)) {
+					// provider (store) higher on the list overrides others below
+					if (combinedStore.getSettingEntries(path, lang) == null) {
+						List<ICLanguageSettingEntry> entries = providerStore.getSettingEntries(path, lang);
+						combinedStore.setSettingEntries(path, lang, entries);
+					}
+				}
+			}
+		}
+
+		return combinedStore;
+	}
 }

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsProvidersSerializer.java

@@ -14,8 +14,10 @@ import java.net.URI;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import org.eclipse.cdt.core.CCorePlugin;
 import org.eclipse.cdt.core.language.settings.providers.ICListenerAgent;
@@ -305,6 +307,26 @@ public class LanguageSettingsProvidersSerializer {
 			return "LanguageSettingsChangeEvent for project=[" + getProjectName() + "]"
 					+ ", configurations=" + deltaMap.keySet();
 		}
+
+		@Override
+		public Set<IResource> getAffectedResources(String cfgId) {
+			LanguageSettingsDelta delta = deltaMap.get(cfgId);
+			if (delta != null) {
+				Set<String> paths = delta.getAffectedResourcePaths();
+				if (!paths.isEmpty()) {
+					IProject project = ResourcesPlugin.getWorkspace().getRoot().getProject(projectName);
+					Set<IResource> resources = new HashSet<IResource>();
+					for (String path : paths) {
+						IResource rc = project.findMember(path);
+						if (rc != null) {
+							resources.add(rc);
+						}
+					}
+					return resources;
+				}
+			}
+			return null;
+		}
 	}
 
 	/** static initializer */

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/LanguageSettingsChangeListener.java

@@ -10,14 +10,23 @@
  *******************************************************************************/
 package org.eclipse.cdt.internal.core.pdom;
 
+import java.util.HashSet;
+import java.util.Set;
+
 import org.eclipse.cdt.core.CCorePlugin;
+import org.eclipse.cdt.core.index.IIndexManager;
 import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsChangeEvent;
 import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsChangeListener;
+import org.eclipse.cdt.core.model.ICElement;
+import org.eclipse.cdt.core.model.ICProject;
 import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
 import org.eclipse.cdt.core.settings.model.ICProjectDescription;
+import org.eclipse.cdt.internal.core.model.CModelManager;
 import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IResource;
 import org.eclipse.core.resources.IWorkspaceRoot;
 import org.eclipse.core.resources.ResourcesPlugin;
+import org.eclipse.core.runtime.CoreException;
 
 /**
  *	This class handles changes in language settings for the PDOM.
@@ -42,16 +51,36 @@ public class LanguageSettingsChangeListener implements ILanguageSettingsChangeLi
 		if (project != null) {
 			ICProjectDescription prjDescription = CCorePlugin.getDefault().getProjectDescription(project);
 			if (prjDescription != null) {
-				ICConfigurationDescription indexedCfgDescription = prjDescription.getDefaultSettingConfiguration();
-				String indexedCfgId = indexedCfgDescription.getId();
+				// cfgDescription being indexed
+				ICConfigurationDescription cfgDescription = prjDescription.getDefaultSettingConfiguration();
+				String indexedId = cfgDescription.getId();
 
-				for (String cfgId : event.getConfigurationDescriptionIds()) {
-					if (cfgId.equals(indexedCfgId)) {
-						fManager.handlePostBuildEvent();
+				for (String id : event.getConfigurationDescriptionIds()) {
+					if (id.equals(indexedId)) {
+						reindex(id, event);
 						return;
 					}
 				}
 			}
 		}
 	}
+
+	private void reindex(String cfgId, ILanguageSettingsChangeEvent event) {
+		CModelManager manager = CModelManager.getDefault();
+		ICProject cProject = manager.getCModel().getCProject(event.getProjectName());
+		Set<ICElement> tuSelection = new HashSet<ICElement>();
+
+		Set<IResource> resources = event.getAffectedResources(cfgId);
+		if (resources != null && !resources.isEmpty()) {
+			for (IResource rc : resources) {
+				tuSelection.add(manager.create(rc, cProject));
+			}
+
+			try {
+				fManager.update(tuSelection.toArray(new ICElement[tuSelection.size()]), IIndexManager.UPDATE_ALL);
+			} catch (CoreException e) {
+				CCorePlugin.log(e);
+			}
+		}
+	}
 }