Don't generate end element on apply completion if it exists

Fixes eclipse-lemminx#651

Signed-off-by: azerr <[email protected]>

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

@@ -378,7 +378,23 @@ public boolean isEndTagClosed() {
 	}
 
 	/**
-	 * If Element has a closing end tag eg: <a> </a> -> true , <a> </b> -> false
+	 * Returns true if the given element is an end tag (eg: </a> which is not
+	 * closed) and false otherwise.
+	 * 
+	 * @param tagName the end tag name.
+	 * @return true if the given element is an end tag (eg: </a> which is not
+	 *         closed) and false otherwise.
+	 */
+	public boolean isOnlyEndTag(String tagName) {
+		return isSameTag(tagName) && hasEndTag() && !hasStartTag();
+	}
+
+	/**
+	 * Returns true if element has a closing end tag (eg: <a> </a>) and false
+	 * otherwise (eg: <a> </b>).
+	 * 
+	 * @return true if element has a closing end tag (eg: <a> </a>) and false
+	 *         otherwise (eg: <a> </b>).
 	 */
 	@Override
 	public boolean isClosed() {

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/ContentModelCompletionParticipant.java

@@ -15,11 +15,13 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 
 import org.eclipse.lemminx.commons.BadLocationException;
 import org.eclipse.lemminx.dom.DOMDocument;
 import org.eclipse.lemminx.dom.DOMElement;
+import org.eclipse.lemminx.dom.DOMNode;
 import org.eclipse.lemminx.extensions.contentmodel.model.CMAttributeDeclaration;
 import org.eclipse.lemminx.extensions.contentmodel.model.CMDocument;
 import org.eclipse.lemminx.extensions.contentmodel.model.CMElementDeclaration;
@@ -219,11 +221,11 @@ private static void addTagName(NodeList list, Set<String> tags, ICompletionReque
 		}
 	}
 
-	private static void addCompletionItem(CMElementDeclaration elementDeclaration, DOMElement element,
+	private static void addCompletionItem(CMElementDeclaration elementDeclaration, DOMElement parentElement,
 			String defaultPrefix, boolean forceUseOfPrefix, ICompletionRequest request, ICompletionResponse response,
 			XMLGenerator generator, Set<String> tags) {
 		String prefix = forceUseOfPrefix ? defaultPrefix
-				: (element != null ? element.getPrefix(elementDeclaration.getNamespace()) : null);
+				: (parentElement != null ? parentElement.getPrefix(elementDeclaration.getNamespace()) : null);
 		String label = elementDeclaration.getName(prefix);
 		if (tags != null) {
 			if (tags.contains(label)) {
@@ -238,12 +240,62 @@ private static void addCompletionItem(CMElementDeclaration elementDeclaration, D
 		item.setKind(CompletionItemKind.Property);
 		MarkupContent documentation = XMLGenerator.createMarkupContent(elementDeclaration, request);
 		item.setDocumentation(documentation);
-		String xml = generator.generate(elementDeclaration, prefix);
+		String xml = generator.generate(elementDeclaration, prefix,
+				isGenerateEndTag(request.getNode(), request.getOffset(), label));
 		item.setTextEdit(new TextEdit(request.getReplaceRange(), xml));
 		item.setInsertTextFormat(InsertTextFormat.Snippet);
 		response.addCompletionItem(item, true);
 	}
 
+	private static boolean isGenerateEndTag(DOMNode node, int offset, String tagName) {
+		if (node == null) {
+			return true;
+		}
+		if (node.isText()) {
+			DOMNode next = node.getNextSibling();
+			if (next == null || !next.isElement()) {
+				return true;
+			}
+			// emp| </employe>
+			DOMElement nextElement = (DOMElement) next;
+			if (nextElement.isOnlyEndTag(tagName)) {
+				return false;
+			}
+			return true;
+		}
+		if (!node.isElement()) {
+			return true;
+		}
+		DOMElement element = (DOMElement) node;
+		if (!element.isInStartTag(offset) && !element.isInEndTag(offset)) {
+			// completion inside element content
+			// <employee>|</employee>
+			// <employee> |</employee>
+			// <employee> | </employee>
+			return true;
+		}
+		if (element.getEnd() <= offset) {
+			// <employee />|
+			// <employee /> |
+			return true;
+		}
+		if (element.isClosed() && element.isSameTag(tagName)) {
+			// <employe|e></employee>
+			return false;
+		}
+		// element is not
+		List<DOMNode> children = element.getChildren();
+		for (DOMNode child : children) {
+			if (child.isElement()) {
+				DOMElement childElement = (DOMElement) child;
+				if (childElement.isOnlyEndTag(tagName)) {
+					return false;
+				}
+			}
+		}
+		return true;
+	}
+
 	@Override
 	public void onAttributeName(boolean generateValue, ICompletionRequest request, ICompletionResponse response)
 			throws Exception {
@@ -356,8 +408,7 @@ public void onXMLContent(ICompletionRequest request, ICompletionResponse respons
 						end = document.positionAt(endOffset);
 					}
 					int completionOffset = request.getOffset();
-					String tokenStart = StringUtils.getWhitespaces(document.getText(), startOffset,
-							completionOffset);
+					String tokenStart = StringUtils.getWhitespaces(document.getText(), startOffset, completionOffset);
 					Range fullRange = new Range(start, end);
 					values.forEach(value -> {
 						CompletionItem item = new CompletionItem();

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/utils/XMLGenerator.java

@@ -65,31 +65,28 @@ public XMLGenerator(XMLFormattingOptions formattingOptions, boolean autoCloseTag
 		this.canSupportSnippets = canSupportSnippets;
 	}
 
-	public String generate(CMElementDeclaration elementDeclaration) {
-		return generate(elementDeclaration, null);
-	}
-
 	/**
 	 * Returns the XML generated from the given element declaration.
 	 * 
 	 * @param elementDeclaration
 	 * @param prefix
 	 * @return the XML generated from the given element declaration.
 	 */
-	public String generate(CMElementDeclaration elementDeclaration, String prefix) {
+	public String generate(CMElementDeclaration elementDeclaration, String prefix, boolean generateEndTag) {
 		XMLBuilder xml = new XMLBuilder(formattingOptions, whitespacesIndent, lineDelimiter);
-		generate(elementDeclaration, prefix, 0, 0, xml, new ArrayList<CMElementDeclaration>());
+		generate(elementDeclaration, prefix, generateEndTag, 0, 0, xml, new ArrayList<CMElementDeclaration>());
 		if (canSupportSnippets) {
 			xml.addContent(SnippetsBuilder.tabstops(0)); // "$0"
 		}
 		return xml.toString();
 	}
 
-	private int generate(CMElementDeclaration elementDeclaration, String prefix, int level, int snippetIndex,
+	private int generate(CMElementDeclaration elementDeclaration, String prefix, boolean generateEndTag, int level, int snippetIndex,
 			XMLBuilder xml, List<CMElementDeclaration> generatedElements) {
 		if (generatedElements.contains(elementDeclaration)) {
 			return snippetIndex;
 		}
+		boolean autoCloseTags = this.autoCloseTags && generateEndTag;
 		generatedElements.add(elementDeclaration);
 		if (level > 0) {
 			xml.linefeed();
@@ -106,7 +103,7 @@ private int generate(CMElementDeclaration elementDeclaration, String prefix, int
 			if ((level > maxLevel)) {
 				level++;
 				for (CMElementDeclaration child : children) {
-					snippetIndex = generate(child, prefix, level, snippetIndex, xml, generatedElements);
+					snippetIndex = generate(child, prefix, true, level, snippetIndex, xml, generatedElements);
 				}
 				level--;
 				xml.linefeed();

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/services/XMLCompletions.java

@@ -495,6 +495,7 @@ private void collectOpenTagSuggestions(boolean hasOpenBracket, Range replaceRang
 				LOGGER.log(Level.SEVERE, "While performing ICompletionParticipant#onTagOpen", e);
 			}
 		}
+		DOMNode currentElement = completionRequest.getNode();
 		DOMElement parentNode = completionRequest.getParentElement();
 		if (parentNode != null && !parentNode.getOwnerDocument().hasGrammar()) {
 			// no grammar, collect similar tags from the parent node
@@ -522,7 +523,7 @@ private void collectOpenTagSuggestions(boolean hasOpenBracket, Range replaceRang
 						if (completionRequest.isCompletionSnippetsSupported()) {
 							xml.append("$0");
 						}
-						if (completionRequest.isAutoCloseTags()) {
+						if (!currentElement.isClosed() && completionRequest.isAutoCloseTags()) {
 							xml.append("</").append(tag).append(">");
 						}
 					}

org.eclipse.lemminx/src/test/java/org/eclipse/lemminx/extensions/contentmodel/XMLSchemaCompletionExtensionsTest.java

@@ -221,7 +221,8 @@ public void noNamespaceSchemaLocationCompletion() throws BadLocationException {
 				"    <View><Name /><|";
 		// Completion only with Name
 		XMLAssert.testCompletionFor(xml, null, "src/test/resources/Format.xml", 5 + 2 /* CDATA and Comments */,
-				c("OutOfBand", "<OutOfBand>false</OutOfBand>"), c("ViewSelectedBy", "<ViewSelectedBy></ViewSelectedBy>"),
+				c("OutOfBand", "<OutOfBand>false</OutOfBand>"),
+				c("ViewSelectedBy", "<ViewSelectedBy></ViewSelectedBy>"),
 				c("End with '</Configuration>'", "/Configuration>"),
 				c("End with '</ViewDefinitions>'", "/ViewDefinitions>"), c("End with '</View>'", "/View>"));
 	}
@@ -1004,6 +1005,66 @@ public void tag() throws BadLocationException {
 
 	}
 
+	@Test
+	public void generateOnlyStartElementOnText() throws BadLocationException {
+		// </employee> already exists, completion must generate only <employee>
+
+		// completion on empty text
+		String xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\r\n" + //
+				"<person xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"xsd/choice.xsd\">\r\n"
+				+ //
+				"|</employee>";
+		testCompletionSnippetSupporytFor(xml, "src/test/resources/choice.xml", 2, //
+				c("member", te(2, 0, 2, 0, "<member>$1</member>$0"), "member"), //
+				c("employee", te(2, 0, 2, 0, "<employee>$1$0"), "employee")); // <-- here only start employee is
+																				// generated
+
+		// completion on text
+		xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\r\n" + //
+				"<person xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"xsd/choice.xsd\">\r\n"
+				+ //
+				"em|</employee>";
+		testCompletionSnippetSupporytFor(xml, "src/test/resources/choice.xml", 2, //
+				c("member", te(2, 0, 2, 2, "<member>$1</member>$0"), "member"), //
+				c("employee", te(2, 0, 2, 2, "<employee>$1$0"), "employee")); // <-- here only start employee is
+																				// generated
+	}
+
+	@Test
+	public void generateOnlyStartElementOnElement() throws BadLocationException {
+		// </employee> already exists, completion must generate only <employee>
+
+		// completion on start tag
+		String xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\r\n" + //
+				"<person xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"xsd/choice.xsd\">\r\n"
+				+ //
+				"<|</employee>";
+		testCompletionSnippetSupporytFor(xml, "src/test/resources/choice.xml", 2, //
+				c("member", te(2, 0, 2, 1, "<member>$1</member>$0"), "<member"), //
+				c("employee", te(2, 0, 2, 1, "<employee>$1$0"), "<employee")); // <-- here only start employee is
+																				// generated
+
+		// completion on start tag element
+		xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\r\n" + //
+				"<person xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"xsd/choice.xsd\">\r\n"
+				+ //
+				"<em|</employee>";
+		testCompletionSnippetSupporytFor(xml, "src/test/resources/choice.xml", 2, //
+				c("member", te(2, 0, 2, 3, "<member>$1</member>$0"), "<member"), //
+				c("employee", te(2, 0, 2, 3, "<employee>$1$0"), "<employee")); // <-- here only start employee is
+																				// generated
+
+		// completion inside tag element
+		xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\r\n" + //
+				"<person xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"xsd/choice.xsd\">\r\n"
+				+ //
+				"<employee|></employee>";
+		testCompletionSnippetSupporytFor(xml, "src/test/resources/choice.xml", 2, //
+				c("member", te(2, 0, 2, 10, "<member>$1</member>$0"), "<member"), //
+				c("employee", te(2, 0, 2, 10, "<employee>$1$0"), "<employee")); // <-- here only start employee is
+																				// generated
+	}
+
 	@Test
 	public void documentationAsPlainText() throws BadLocationException {
 		String xml = "<project xmlns=\"http://maven.apache.org/POM/4.0.0\"\r\n" + //
@@ -1019,7 +1080,6 @@ public void documentationAsPlainText() throws BadLocationException {
 						System.lineSeparator() + //
 						"Source: maven-4.0.0.xsd",
 				MarkupKind.PLAINTEXT));
-
 	}
 
 	@Test