Merge pull request #663 from eclipse/sz/bug361216

[361216] Improved logic that registers scope wrappers

org.eclipse.xtext.tests/src/org/eclipse/xtext/scoping/impl/DelegatingScopeProviderTest.java

@@ -0,0 +1,159 @@
+/*******************************************************************************
+ * Copyright (c) 2018 itemis AG (http://www.itemis.eu) 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
+ *******************************************************************************/
+package org.eclipse.xtext.scoping.impl;
+
+import org.eclipse.emf.ecore.EObject;
+import org.eclipse.emf.ecore.EReference;
+import org.eclipse.xtext.scoping.IScope;
+import org.eclipse.xtext.scoping.IScopeProvider;
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ * @author Sebastian Zarnekow - Initial contribution and API
+ */
+public class DelegatingScopeProviderTest implements IScopeWrapper {
+
+	static class TestableDelegatingScopeProvider implements IDelegatingScopeProvider {
+
+		private final IScopeProvider delegate;
+
+		private int invocationCount = 0;
+		
+		TestableDelegatingScopeProvider(IScopeProvider delegate) {
+			this.delegate = delegate;
+		}
+		
+		TestableDelegatingScopeProvider() {
+			this(new IScopeProvider() {
+				@Override
+				public IScope getScope(EObject context, EReference reference) {
+					return IScope.NULLSCOPE;
+				}
+			});
+		}
+		
+		@Override
+		public void setWrapper(IScopeWrapper wrapper) {
+			invocationCount++;
+			IDelegatingScopeProvider.super.setWrapper(wrapper);
+		}
+		
+		@Override
+		public IScope getScope(EObject context, EReference reference) {
+			Assert.fail("Unexpected invocation");
+			return null;
+		}
+
+		@Override
+		public IScopeProvider getDelegate() {
+			return delegate;
+		}
+		
+	}
+	
+	@Override
+	public IScope wrap(IScope scope) {
+		Assert.fail("Unexpected invocation");
+		return null;
+	}
+	
+	@Test
+	public void testNoSuitableDelegate() {
+		TestableDelegatingScopeProvider testMe = new TestableDelegatingScopeProvider();
+		testMe.setWrapper(this);
+		Assert.assertEquals(1, testMe.invocationCount);
+		
+		IDelegatingScopeProvider.setWrapper(testMe, null);
+		Assert.assertEquals(2, testMe.invocationCount);
+	}
+	
+	@Test
+	public void testOneSuitableDelegate_01() {
+		TestableDelegatingScopeProvider root = new TestableDelegatingScopeProvider();
+		TestableDelegatingScopeProvider delegating = new TestableDelegatingScopeProvider(root);
+		
+		delegating.setWrapper(this);
+		Assert.assertEquals(1, delegating.invocationCount);
+		Assert.assertEquals(1, root.invocationCount);
+		
+		IDelegatingScopeProvider.setWrapper(delegating, null);
+		Assert.assertEquals(2, delegating.invocationCount);
+		Assert.assertEquals(2, root.invocationCount);
+	}
+	
+	@Test
+	public void testOneSuitableDelegate_02() {
+		final int[] invocationCount = new int[] { 0 };
+		AbstractGlobalScopeDelegatingScopeProvider root = new AbstractGlobalScopeDelegatingScopeProvider() {
+			
+			@Override
+			public IScope getScope(EObject context, EReference reference) {
+				return IScope.NULLSCOPE;
+			}
+			
+			@Override
+			public void setWrapper(IScopeWrapper wrapper) {
+				invocationCount[0]++;
+				Assert.assertEquals(DelegatingScopeProviderTest.this, wrapper);
+				super.setWrapper(wrapper);
+			}
+		};
+		TestableDelegatingScopeProvider delegating = new TestableDelegatingScopeProvider(root);
+		
+		delegating.setWrapper(this);
+		Assert.assertEquals(1, delegating.invocationCount);
+		Assert.assertEquals(1, invocationCount[0]);
+	}
+	
+	@Test
+	public void testTwoSuitableDelegates_02() {
+		final int[] invocationCount = new int[] { 0 };
+		AbstractGlobalScopeDelegatingScopeProvider first = new AbstractGlobalScopeDelegatingScopeProvider() {
+			
+			@Override
+			public IScope getScope(EObject context, EReference reference) {
+				return IScope.NULLSCOPE;
+			}
+			
+			@Override
+			public void setWrapper(IScopeWrapper wrapper) {
+				invocationCount[0]++;
+				Assert.assertEquals(DelegatingScopeProviderTest.this, wrapper);
+				super.setWrapper(wrapper);
+			}
+		};
+		AbstractGlobalScopeDelegatingScopeProvider second = new AbstractGlobalScopeDelegatingScopeProvider() {
+			
+			@Override
+			public IScope getScope(EObject context, EReference reference) {
+				return IScope.NULLSCOPE;
+			}
+			
+			@Override
+			public void setWrapper(IScopeWrapper wrapper) {
+				invocationCount[0]++;
+				Assert.assertEquals(DelegatingScopeProviderTest.this, wrapper);
+				super.setWrapper(wrapper);
+			}
+		};
+		
+		TestableDelegatingScopeProvider delegating = new TestableDelegatingScopeProvider(first) {
+			@Override
+			public void setWrapper(IScopeWrapper wrapper) {
+				IDelegatingScopeProvider.setWrapper(second, wrapper);
+				super.setWrapper(wrapper);
+			};
+		};
+		
+		delegating.setWrapper(this);
+		Assert.assertEquals(1, delegating.invocationCount);
+		Assert.assertEquals(2, invocationCount[0]);
+	}
+
+}

org.eclipse.xtext/src/org/eclipse/xtext/linking/impl/DefaultLinkingService.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2008, 2017 itemis AG (http://www.itemis.eu) and others.
+ * Copyright (c) 2008, 2018 itemis AG (http://www.itemis.eu) 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
@@ -21,7 +21,6 @@ import org.eclipse.xtext.nodemodel.INode;
 import org.eclipse.xtext.resource.IEObjectDescription;
 import org.eclipse.xtext.scoping.IScope;
 import org.eclipse.xtext.scoping.IScopeProvider;
-import org.eclipse.xtext.scoping.impl.AbstractGlobalScopeDelegatingScopeProvider;
 import org.eclipse.xtext.scoping.impl.IDelegatingScopeProvider;
 
 import com.google.inject.Inject;
@@ -67,13 +66,7 @@ public class DefaultLinkingService extends AbstractLinkingService {
 	}
 	
 	protected void unRegisterImportedNamesAdapter(IScopeProvider scopeProvider) {
-		if (scopeProvider instanceof AbstractGlobalScopeDelegatingScopeProvider) {
-			AbstractGlobalScopeDelegatingScopeProvider provider = (AbstractGlobalScopeDelegatingScopeProvider) scopeProvider;
-			provider.setWrapper(null);
-		} else if (scopeProvider instanceof IDelegatingScopeProvider) {
-			IDelegatingScopeProvider delegatingScopeProvider = (IDelegatingScopeProvider) scopeProvider;
-			unRegisterImportedNamesAdapter(delegatingScopeProvider.getDelegate());
-		}
+		IDelegatingScopeProvider.setWrapper(scopeProvider, null);
 	}
 
 	protected void registerImportedNamesAdapter(EObject context) {
@@ -81,14 +74,8 @@ public class DefaultLinkingService extends AbstractLinkingService {
 	}
 	
 	protected void registerImportedNamesAdapter(IScopeProvider scopeProvider, EObject context) {
-		if (scopeProvider instanceof AbstractGlobalScopeDelegatingScopeProvider) {
-			AbstractGlobalScopeDelegatingScopeProvider provider = (AbstractGlobalScopeDelegatingScopeProvider) scopeProvider;
-			ImportedNamesAdapter adapter = getImportedNamesAdapter(context);
-			provider.setWrapper(adapter);
-		} else if (scopeProvider instanceof IDelegatingScopeProvider) {
-			IDelegatingScopeProvider delegatingScopeProvider = (IDelegatingScopeProvider) scopeProvider;
-			registerImportedNamesAdapter(delegatingScopeProvider.getDelegate(), context);
-		}
+		ImportedNamesAdapter adapter = getImportedNamesAdapter(context);
+		IDelegatingScopeProvider.setWrapper(scopeProvider, adapter);
 	}
 
 	protected ImportedNamesAdapter getImportedNamesAdapter(EObject context) {

org.eclipse.xtext/src/org/eclipse/xtext/scoping/impl/IDelegatingScopeProvider.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011 itemis AG (http://www.itemis.eu) and others.
+ * Copyright (c) 2011, 2018 itemis AG (http://www.itemis.eu) 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
@@ -29,4 +29,34 @@ public interface IDelegatingScopeProvider extends IScopeProvider {
 	 */
 	IScopeProvider getDelegate();
 	
+	/**
+	 * Set the wrapper this delegating scope provider. This encapsulates the traversal of the
+	 * delegate and allows clients to set the wrapper on multiple delegates if necessary.
+	 * 
+	 * The wrapper may be <code>null</code>
+	 * 
+	 * @since 2.14
+	 */
+	default void setWrapper(IScopeWrapper wrapper) {
+		setWrapper(getDelegate(), wrapper);
+	}
+	
+	/**
+	 * Set the given wrapper on the given {@link IScopeProvider} if the scope provider is either a
+	 * delegating scope provider or an {@link AbstractGlobalScopeDelegatingScopeProvider}.
+	 * 
+	 * The wrapper may be <code>null</code>
+	 * 
+	 * @since 2.14
+	 */
+	static void setWrapper(IScopeProvider scopeProvider, IScopeWrapper wrapper) {
+		if (scopeProvider instanceof AbstractGlobalScopeDelegatingScopeProvider) {
+			AbstractGlobalScopeDelegatingScopeProvider provider = (AbstractGlobalScopeDelegatingScopeProvider) scopeProvider;
+			provider.setWrapper(wrapper);
+		} else if (scopeProvider instanceof IDelegatingScopeProvider) {
+			IDelegatingScopeProvider delegatingScopeProvider = (IDelegatingScopeProvider) scopeProvider;
+			delegatingScopeProvider.setWrapper(wrapper);
+		}
+	}
+	
 }