Completion for external declared entity

Fixes eclipse-lemminx#660

Signed-off-by: azerr <azerr@redhat.com>

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/dom/DTDEntityDecl.java

@@ -104,7 +104,7 @@ public String getInputEncoding() {
 	 */
 	@Override
 	public String getNotationName() {
-		throw new UnsupportedOperationException();
+		return getValue();
 	}
 
 	/*

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/model/CMDocument.java

@@ -13,10 +13,13 @@
 package org.eclipse.lemminx.extensions.contentmodel.model;
 
 import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
 
 import org.eclipse.lemminx.dom.DOMElement;
 import org.eclipse.lemminx.dom.DOMNode;
 import org.eclipse.lsp4j.LocationLink;
+import org.w3c.dom.Entity;
 
 /**
  * Content model document which abstracts element declaration from a given
@@ -72,4 +75,13 @@ public interface CMDocument {
 	 * @return true if the content model document is dirty and false otherwise.
 	 */
 	boolean isDirty();
+
+	/**
+	 * Returns list of declared entities.
+	 * 
+	 * @return list of declared entities.
+	 */
+	default List<Entity> getEntities() {
+		return Collections.emptyList();
+	}
 }

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/dtd/contentmodel/CMDTDDocument.java

@@ -24,19 +24,22 @@
 
 import org.apache.xerces.impl.dtd.DTDGrammar;
 import org.apache.xerces.impl.dtd.XMLDTDLoader;
+import org.apache.xerces.impl.dtd.XMLEntityDecl;
 import org.apache.xerces.xni.Augmentations;
 import org.apache.xerces.xni.XMLString;
 import org.apache.xerces.xni.XNIException;
 import org.apache.xerces.xni.grammars.Grammar;
 import org.apache.xerces.xni.parser.XMLInputSource;
 import org.eclipse.lemminx.dom.DOMElement;
 import org.eclipse.lemminx.dom.DOMNode;
+import org.eclipse.lemminx.dom.DTDEntityDecl;
 import org.eclipse.lemminx.extensions.contentmodel.model.CMAttributeDeclaration;
 import org.eclipse.lemminx.extensions.contentmodel.model.CMDocument;
 import org.eclipse.lemminx.extensions.contentmodel.model.CMElementDeclaration;
 import org.eclipse.lemminx.extensions.contentmodel.model.FilesChangedTracker;
 import org.eclipse.lemminx.extensions.dtd.utils.DTDUtils;
 import org.eclipse.lsp4j.LocationLink;
+import org.w3c.dom.Entity;
 
 /**
  * DTD document.
@@ -46,7 +49,6 @@
  */
 public class CMDTDDocument extends XMLDTDLoader implements CMDocument {
 
-
 	static class DTDNodeInfo {
 
 		private String comment;
@@ -100,6 +102,8 @@ public String getComment(String attrName) {
 	private Map<String, DTDNodeInfo> attributes;
 	private DTDNodeInfo nodeInfo;
 
+	private List<Entity> entities;
+
 	public CMDTDDocument() {
 		this(null);
 	}
@@ -213,8 +217,8 @@ public void attributeDecl(String elementName, String attributeName, String type,
 			nodeInfo.setComment(comment);
 			attributes.put(attributeName, nodeInfo);
 		}
-		super.attributeDecl(elementName, attributeName, type, enumeration, defaultType, defaultValue, nonNormalizedDefaultValue,
-				augs);
+		super.attributeDecl(elementName, attributeName, type, enumeration, defaultType, defaultValue,
+				nonNormalizedDefaultValue, augs);
 	}
 
 	@Override
@@ -298,4 +302,56 @@ public boolean isDirty() {
 		return tracker != null ? tracker.isDirty() : null;
 	}
 
+	@Override
+	public List<Entity> getEntities() {
+		if (entities == null) {
+			entities = computeEntities();
+		}
+		return entities;
+	}
+
+	private synchronized List<Entity> computeEntities() {
+		if (entities != null) {
+			return entities;
+		}
+		List<Entity> entities = new ArrayList<>();
+		fillEntities(fDTDGrammar, entities);
+		return entities;
+	}
+
+	/**
+	 * Collect entities declared in the DTD grammar.
+	 * 
+	 * @param grammar  the DTD grammar.
+	 * @param entities list to fill.
+	 */
+	private static void fillEntities(DTDGrammar grammar, List<Entity> entities) {
+		int index = 0;
+		XMLEntityDecl entityDecl = new XMLEntityDecl() {
+
+			@Override
+			public void setValues(String name, String publicId, String systemId, String baseSystemId, String notation,
+					String value, boolean isPE, boolean inExternal) {
+				if (inExternal && !isPE) {
+					// Only external entities (entities declared in the DTD) and not entity with %
+					// must be collected.
+					Entity entity = new DTDEntityDecl(0, 0) {
+						@Override
+						public String getNodeName() {
+							return name;
+						}
+
+						@Override
+						public String getNotationName() {
+							return value;
+						}
+					};
+					entities.add(entity);
+				}
+			};
+		};
+		while (grammar.getEntityDecl(index, entityDecl)) {
+			index++;
+		}
+	}
 }

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/entities/EntitiesCompletionParticipant.java

@@ -12,9 +12,12 @@
  */
 package org.eclipse.lemminx.extensions.entities;
 
+import java.util.List;
+
 import org.eclipse.lemminx.dom.DOMDocument;
 import org.eclipse.lemminx.dom.DOMDocumentType;
-import org.eclipse.lemminx.dom.DTDEntityDecl;
+import org.eclipse.lemminx.extensions.contentmodel.model.CMDocument;
+import org.eclipse.lemminx.extensions.contentmodel.model.ContentModelManager;
 import org.eclipse.lemminx.extensions.entities.EntitiesDocumentationUtils.PredefinedEntity;
 import org.eclipse.lemminx.services.extensions.CompletionParticipantAdapter;
 import org.eclipse.lemminx.services.extensions.ICompletionRequest;
@@ -26,6 +29,7 @@
 import org.eclipse.lsp4j.MarkupKind;
 import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.TextEdit;
+import org.w3c.dom.Entity;
 import org.w3c.dom.NamedNodeMap;
 
 /**
@@ -40,34 +44,63 @@ public void onXMLContent(ICompletionRequest request, ICompletionResponse respons
 		if (entityRange == null) {
 			return;
 		}
-		boolean markdown = request.canSupportMarkupKind(MarkupKind.MARKDOWN);
 		// There is the '&' character before the offset where completion was triggered
-		collectCharacterEntityProposals(entityRange, markdown, request, response);
+		boolean markdown = request.canSupportMarkupKind(MarkupKind.MARKDOWN);
+		DOMDocument document = request.getXMLDocument();
+		collectInternalEntityProposals(document, entityRange, markdown, response);
+		collectExternalEntityProposals(document, entityRange, markdown, request, response);
 		collectPredefinedEntityProposals(entityRange, markdown, request, response);
 	}
 
 	/**
-	 * Collect locally declare entities.
+	 * Collect internal entities.
 	 * 
+	 * @param document    the DOM document.
 	 * @param entityRange the entity range.
-	 * @param markdown
+	 * @param markdown    true if the documentation can be formatted as markdown and
+	 *                    false otherwise.
 	 * @param request     the completion request.
 	 * @param response    the completion response.
-	 * 
 	 */
-	private static void collectCharacterEntityProposals(Range entityRange, boolean markdown, ICompletionRequest request,
+	private static void collectInternalEntityProposals(DOMDocument document, Range entityRange, boolean markdown,
 			ICompletionResponse response) {
-		DOMDocument document = request.getXMLDocument();
 		DOMDocumentType docType = document.getDoctype();
 		if (docType == null) {
 			return;
 		}
 		NamedNodeMap entities = docType.getEntities();
 		for (int i = 0; i < entities.getLength(); i++) {
-			DTDEntityDecl entity = (DTDEntityDecl) entities.item(i);
-			if (entity.getName() != null) {
+			Entity entity = (Entity) entities.item(i);
+			if (entity.getNodeName() != null) {
 				// provide completion for the locally declared entity
-				fillCompletion(entity.getName(), entity.getValue(), false, entityRange, markdown, response);
+				fillCompletion(entity.getNodeName(), entity.getNotationName(), false, false, entityRange, markdown,
+						response);
+			}
+		}
+	}
+
+	/**
+	 * Collect external entities.
+	 * 
+	 * @param document    the DOM document.
+	 * @param entityRange the entity range.
+	 * @param markdown    true if the documentation can be formatted as markdown and
+	 *                    false otherwise.
+	 * @param request     the completion request.
+	 * @param response    the completion response.
+	 */
+	private static void collectExternalEntityProposals(DOMDocument document, Range entityRange, boolean markdown,
+			ICompletionRequest request, ICompletionResponse response) {
+		ContentModelManager contentModelManager = request.getComponent(ContentModelManager.class);
+		CMDocument cmDocument = contentModelManager.findCMDocument(document, null);
+		if (cmDocument != null) {
+			List<Entity> entities = cmDocument.getEntities();
+			for (Entity entity : entities) {
+				if (entity.getNodeName() != null) {
+					// provide completion for the external declared entity
+					fillCompletion(entity.getNodeName(), entity.getNotationName(), true, false, entityRange, markdown,
+							response);
+				}
 			}
 		}
 	}
@@ -76,23 +109,23 @@ private static void collectCharacterEntityProposals(Range entityRange, boolean m
 	 * Collect predefined entities.
 	 * 
 	 * @param entityRange the entity range.
-	 * @param markdown
+	 * @param markdown    true if the documentation can be formatted as markdown and
+	 *                    false otherwise.
 	 * @param request     the completion request.
 	 * @param response    the completion response.
 	 * 
 	 * @see https://www.w3.org/TR/xml/#sec-predefined-ent
 	 */
 	private void collectPredefinedEntityProposals(Range entityRange, boolean markdown, ICompletionRequest request,
 			ICompletionResponse response) {
-		// see https://www.w3.org/TR/xml/#sec-predefined-ent
 		PredefinedEntity[] entities = PredefinedEntity.values();
 		for (PredefinedEntity entity : entities) {
-			fillCompletion(entity.name(), entity.getValue(), true, entityRange, markdown, response);
+			fillCompletion(entity.name(), entity.getValue(), false, true, entityRange, markdown, response);
 		}
 	}
 
-	private static void fillCompletion(String name, String entityValue, boolean predefined, Range entityRange,
-			boolean markdown, ICompletionResponse response) {
+	private static void fillCompletion(String name, String entityValue, boolean external, boolean predefined,
+			Range entityRange, boolean markdown, ICompletionResponse response) {
 		String entityName = "&" + name + ";";
 		CompletionItem item = new CompletionItem();
 		item.setLabel(entityName);
@@ -101,7 +134,8 @@ private static void fillCompletion(String name, String entityValue, boolean pred
 		String insertText = entityName;
 		item.setFilterText(insertText);
 		item.setTextEdit(new TextEdit(entityRange, insertText));
-		item.setDocumentation(EntitiesDocumentationUtils.getDocumentation(name, entityValue, predefined, markdown));
+		item.setDocumentation(
+				EntitiesDocumentationUtils.getDocumentation(name, entityValue, external, predefined, markdown));
 		response.addCompletionItem(item);
 	}
 

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/entities/EntitiesDocumentationUtils.java

@@ -45,8 +45,19 @@ public String getValue() {
 	private EntitiesDocumentationUtils() {
 	}
 
-	public static MarkupContent getDocumentation(String entityName, String entityValue, boolean predefined,
-			boolean markdown) {
+	/**
+	 * Returns the entity documentation.
+	 * 
+	 * @param entityName  the entity name.
+	 * @param entityValue the entity value.
+	 * @param external    true if it's an external entity and false otherwise.
+	 * @param predefined  true if it's an predefined entity and false otherwise.
+	 * @param markdown    true if the documentation can be formatted as markdown and
+	 *                    false otherwise.
+	 * @return the entity documentation.
+	 */
+	public static MarkupContent getDocumentation(String entityName, String entityValue, boolean external,
+			boolean predefined, boolean markdown) {
 		StringBuilder documentation = new StringBuilder();
 
 		// Title
@@ -62,6 +73,7 @@ public static MarkupContent getDocumentation(String entityName, String entityVal
 		if (entityValue != null && !entityValue.isEmpty()) {
 			addParameter("Value", entityValue, documentation, markdown);
 		}
+		addParameter("External", String.valueOf(external), documentation, markdown);
 		addParameter("Predefined", String.valueOf(predefined), documentation, markdown);
 
 		documentation.append(System.lineSeparator());

org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/entities/EntitiesCompletionExtensionsTest.java

@@ -26,6 +26,8 @@
  */
 public class EntitiesCompletionExtensionsTest {
 
+	// Test for internal entities
+
 	@Test
 	public void afterAmp() throws BadLocationException {
 		// &|
@@ -93,7 +95,7 @@ public void insideWithAmp() throws BadLocationException {
 	}
 
 	@Test
-	public void nonep() throws BadLocationException {
+	public void none() throws BadLocationException {
 		String xml = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\r\n" + //
 				"<!DOCTYPE article [\r\n" + //
 				"  <!ENTITY mdash \"&#x2014;\">\r\n" + //
@@ -103,4 +105,22 @@ public void nonep() throws BadLocationException {
 				"</root>";
 		testCompletionFor(xml, 2 + 2 /* CDATA and Comments */);
 	}
+
+	// Test for external entities
+	@Test
+	public void external() throws BadLocationException {
+		String xml = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\r\n" + //
+				"<!DOCTYPE root-element SYSTEM \"src/test/resources/dtd/base.dtd\" [\r\n" + //
+				"	<!ENTITY mdash \"&#x2014;\">\r\n" + //
+				"]>\r\n" + //
+				"<root-element>\r\n" + //
+				"\r\n &|" + //
+				"</root-element>";
+		testCompletionFor(xml, null, "test.xml", 2 + //
+				2 /* CDATA and Comments */ + //
+				PredefinedEntity.values().length /* predefined entities */,
+				c("&mdash;", "&mdash;", r(6, 1, 6, 2), "&mdash;"), //
+				c("&foo;", "&foo;", r(6, 1, 6, 2), "&foo;"));
+	}
+
 }

org.eclipse.lemminx/src/test/resources/xml/base.xml

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <!DOCTYPE root-element SYSTEM "../dtd/base.dtd" [
-
+	<!ENTITY mdash "&#x2014;">
 ]>
-<root-element />
+<root-element>
+
+</root-element>