Examples with ScopeBasedSelectable org.eclipse.xtext.scoping.impl.ScopeBasedSelectable used on opensource projects

Example 1 with ScopeBasedSelectable

use of org.eclipse.xtext.scoping.impl.ScopeBasedSelectable in project dsl-devkit by dsldevkit.

the class EPackageScopeProvider method scope_EPackage.

/**
 * Scope for {@link EPackage}. These are read from the registry as well as from the {@link Grammar Xtext grammar} corresponding
 * to the scope model (if any).
 *
 * @param context
 *          context scope DSL model (usually the root element, but any object will do)
 * @param reference
 *          context reference (unused for the time being)
 * @return scope with all available {@link EPackage EPackages} with {@link EPackage#getNsURI()} as name
 */
// CHECKSTYLE:OFF
public IScope scope_EPackage(final EObject context, final EReference reference) {
    // CHECKSTYLE:ON
    Resource rsc = context.eResource();
    IScope result = IScope.NULLSCOPE;
    // Add packages from the registry first.
    final Registry packageRegistry = EPackage.Registry.INSTANCE;
    result = new AbstractScope(result, false) {

        @Override
        protected IEObjectDescription getSingleLocalElementByName(final QualifiedName name) {
            return getEPackage(nameConverter.toString(name));
        }

        @Override
        protected Iterable<IEObjectDescription> getAllLocalElements() {
            return Iterables.filter(Iterables.transform(Sets.newHashSet(packageRegistry.keySet()), this::getEPackage), Predicates.notNull());
        }

        private IEObjectDescription getEPackage(final String nsURI) {
            try {
                EPackage ePackage = packageRegistry.getEPackage(nsURI);
                return ePackage != null ? EObjectDescription.create(QualifiedName.create(nsURI), ePackage) : null;
            // CHECKSTYLE:OFF
            } catch (Exception e) {
                // CHECKSTYLE:ON
                // $NON-NLS-1$
                LOG.warn("could not load package " + nsURI, e);
                return null;
            }
        }
    };
    // Add the index
    IResourceDescriptions descriptions = descriptionsProvider.getResourceDescriptions(context.eResource());
    if (descriptions != null) {
        result = SelectableBasedScope.createScope(result, descriptions, EcorePackage.Literals.EPACKAGE, false);
    }
    // Add the global scope
    result = SelectableBasedScope.createScope(result, new ScopeBasedSelectable(globalScopeProvider.getScope(rsc, reference, null)), EcorePackage.Literals.EPACKAGE, false);
    // Now add all packages from the grammar
    final URI grammarUri = rsc.getURI().trimFileExtension().appendFileExtension(XTEXT_EXTENSION);
    final ResourceSet resourceSet = rsc.getResourceSet();
    final URIConverter uriConverter = resourceSet.getURIConverter();
    if (uriConverter.exists(grammarUri, null)) {
        final Resource grammarResource = resourceSet.getResource(grammarUri, true);
        if (grammarResource != null && !grammarResource.getContents().isEmpty()) {
            final Grammar grammar = (Grammar) grammarResource.getContents().get(0);
            final IScope parent = result;
            result = new SimpleScope(parent, Iterables.transform(Iterables.filter(getGrammarEPackages(grammar), Predicates.notNull()), new Function<EPackage, IEObjectDescription>() {

                @Override
                public IEObjectDescription apply(final EPackage param) {
                    return EObjectDescription.create(param.getNsURI(), param);
                }
            }));
        }
    }
    return result;
}