isAvailableObject(): Exclude elements nested IProjectRoot elements

* E.g., elements in DSE ModelSnapshots

Issue-Ref: 4092
Issue-Url: af3#4092




Signed-off-by: Simon Barner <barner@fortiss.org>

org.fortiss.tooling.base/src/org/fortiss/tooling/base/annotation/valueprovider/.ratings

 AnnotationInstSpec.java 7a6cb55bfa9cafa9ead1f72089e554ee8142e8bf GREEN
 DerivedAnnotationValueProviderBase.java afedd21d3469127bbb20adb34c191b5c9c980f6c GREEN
-EStructuralFeatureDescriptor.java 9665d0d3040278243dd37591535e411a90fa63bf GREEN
+EStructuralFeatureDescriptor.java 169ece3fc0740c6ca1e5dde06a1be577d7cb9f80 YELLOW
 EStructuralFeatureValueProviderBase.java 287facbbce47c16d892bae82a214f64ceeef2263 GREEN
 IAnnotationValueProvider.java 08e0e5f66dc97865e9ac03e1ac646af332845e14 GREEN
 ValueProviderBase.java e4e866840845346ec99a4304048f5327c4890996 GREEN

org.fortiss.tooling.base/src/org/fortiss/tooling/base/annotation/valueprovider/EStructuralFeatureDescriptor.java

@@ -15,6 +15,8 @@
 +--------------------------------------------------------------------------*/
 package org.fortiss.tooling.base.annotation.valueprovider;
 
+import static org.fortiss.tooling.kernel.utils.KernelModelElementUtils.getParentElement;
+
 import java.util.HashMap;
 import java.util.Map;
 
@@ -29,6 +31,7 @@ import org.eclipse.emf.ecore.EStructuralFeature;
 import org.fortiss.tooling.base.model.element.IAnnotatedSpecification;
 import org.fortiss.tooling.base.model.element.IDerivedAnnotation;
 import org.fortiss.tooling.base.model.element.IModelElement;
+import org.fortiss.tooling.kernel.model.IProjectRootElement;
 
 /**
  * Description of a {@link EStructuralFeature} managed by a
@@ -150,9 +153,43 @@ public class EStructuralFeatureDescriptor {
 	 */
 	public boolean isAvailableObject(EObject obj, IAnnotatedSpecification specification,
 			EObject modelElement) {
+
+		// Prevent elements at are contained in nested IProjectRoot elements from being listed
+		// (e.g., elements in DSE ModelSnapshots).
+		boolean rootElementSeen = false;
+		while(obj != null) {
+			if(obj instanceof IProjectRootElement) {
+				if(rootElementSeen) {
+					return false;
+				}
+				rootElementSeen = true;
+			}
+			obj = obj.eContainer();
+		}
+
 		return true;
 	}
 
+	/**
+	 * For the given {@link IModelElement}, return the model element used as the scope to provide
+	 * reference values.
+	 */
+	public EObject getValueRootElement(IModelElement modelElement) {
+		switch(getEReferenceScope()) {
+			case PROJECT:
+				IProjectRootElement rootElement =
+						getParentElement(modelElement, IProjectRootElement.class, true);
+				return rootElement != null ? rootElement.eContainer() : null;
+			case MODEL:
+				return getParentElement(modelElement, IProjectRootElement.class, true);
+			case SUB_MODEL:
+			case STRICT_SUB_MODEL:
+				return modelElement;
+			default:
+				throw new RuntimeException("Unsupported reference scope: " + getEReferenceScope());
+		}
+	}
+
 	/**
 	 * Returns the type of the structural feature managed by this
 	 * {@link EStructuralFeatureDescriptor}.