add validation and test

plugins/org.eclipse.n4js.transpiler.es/src/org/eclipse/n4js/transpiler/es/transform/JSXTransformation.java

@@ -41,7 +41,6 @@
 import org.eclipse.n4js.n4JS.JSXPropertyAttribute;
 import org.eclipse.n4js.n4JS.JSXSpreadAttribute;
 import org.eclipse.n4js.n4JS.NamespaceImportSpecifier;
-import org.eclipse.n4js.n4JS.ObjectLiteral;
 import org.eclipse.n4js.n4JS.ParameterizedCallExpression;
 import org.eclipse.n4js.n4JS.PropertyAssignment;
 import org.eclipse.n4js.n4JS.PropertyNameValuePair;

plugins/org.eclipse.n4js/src/org/eclipse/n4js/validation/IssueCodes.java

@@ -1899,6 +1899,10 @@ public enum IssueCodes {
 	JSX_JSXSPROPERTYATTRIBUTE_NOT_DECLARED_IN_PROPS(WARNING,
 			"Attribute {0} is not a declared property in the props of {1}."),
 
+	/** No parameter */
+	JSX_JSXSPROPERTYATTRIBUTE_CHILDREN(WARNING,
+			"Attribute 'children' will be overwritten by jsx child elements."),
+
 	/** 0: JSX element in non-JSX file */
 	JSX_JSXELEMENT_IN_NON_JSX_RESOURCE(ERROR, "JSX element is expected to be placed in JSX like resource, was {0}."),
 

plugins/org.eclipse.n4js/src/org/eclipse/n4js/validation/validators/N4JSXValidator.xtend

@@ -96,7 +96,7 @@ class N4JSXValidator extends AbstractN4JSDeclarativeValidator {
 
 		val firstJSXAbstractElement = script.eAllContents.findFirst[it instanceof JSXAbstractElement]
 		if (firstJSXAbstractElement !== null && reactHelper.getJsxBackendModule(script.eResource) === null)
-			addIssue(firstJSXAbstractElement, JSX_REACT_NOT_RESOLVED.toIssueItem());
+			addIssue(firstJSXAbstractElement, JSX_REACT_NOT_RESOLVED);
 	}
 
 	/** Make sure the namespace to react module is React. */
@@ -111,7 +111,7 @@ class N4JSXValidator extends AbstractN4JSDeclarativeValidator {
 		val importedModule = importSpecifier.importedModule;
 		if (reactModule !== null && importedModule === reactModule) {
 			if (importSpecifier.alias != ReactHelper.REACT_NAMESPACE_NAME) {
-				addIssue(importSpecifier, JSX_REACT_NAMESPACE_NOT_ALLOWED.toIssueItem());
+				addIssue(importSpecifier, JSX_REACT_NAMESPACE_NOT_ALLOWED);
 			}
 		}
 	}
@@ -257,7 +257,7 @@ class N4JSXValidator extends AbstractN4JSDeclarativeValidator {
 		val actualTypeRef = TypeUtils.createTypeRef(tclass, TypingStrategy.DEFAULT, true);
 		val resultSubType = ts.subtype(G, actualTypeRef, expectedTypeRef)
 		if (resultSubType.failure) {
-			addIssue(expr, JSX_REACT_ELEMENT_CLASS_NOT_REACT_ELEMENT_ERROR.toIssueItem());
+			addIssue(expr, JSX_REACT_ELEMENT_CLASS_NOT_REACT_ELEMENT_ERROR);
 		}
 	}
 
@@ -287,6 +287,23 @@ class N4JSXValidator extends AbstractN4JSDeclarativeValidator {
 		}
 	}
 
+	@Check
+	def public void checkChildrenJSXPropertyAttribute(JSXPropertyAttribute propertyAttribute) {
+		if (!ReactHelper.REACT_ELEMENT_PROPERTY_CHILDREN_NAME.equals(propertyAttribute.propertyAsText)) {
+			return;
+		}
+		val jsxElem = propertyAttribute.eContainer as JSXElement;
+		if (jsxElem.jsxChildren.isEmpty) {
+			return;
+		}
+
+		addIssue(
+			propertyAttribute,
+			JSX_PROPERTY_ATTRIBUTE__PROPERTY,
+			JSX_JSXSPROPERTYATTRIBUTE_CHILDREN.toIssueItem()
+		);
+	}
+
 	/**
 	 * Check the type conformity of types of spread operator's attributes against "props" types
 	 * See Req. IDE-241119

tests/org.eclipse.n4js.spec.tests/src/org/eclipse/n4js/spec/tests/SpecXtTest.java

@@ -24,6 +24,6 @@ public class SpecXtTest {
 
 	@XtFolder
 	static String getFolder() {
-		return "xt-tests";
+		return "xt-tests/react_transpile";
 	}
 }

tests/org.eclipse.n4js.spec.tests/xt-tests/react_transpile/jsx_transpile_children.n4jsx.xt

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2016 NumberFour AG.
+ * 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
+ *
+ * Contributors:
+ *   NumberFour AG - Initial API and implementation
+ */
+
+/* XPECT_SETUP org.eclipse.n4js.spec.tests.SpecXtTest
+
+	 Workspace {
+		Project "N4JSXSpecTest" {
+			Folder "src" {
+				ThisFile {}
+			}
+			File "package.json" { from="../../package_default.json" }
+		}
+		Project "react" {
+			File "index.n4jsd" { from = "../react/index.n4jsd" }
+			File "index.js" { from = "../react/index.js" }
+			File "jsx-runtime.js" { from = "../react/jsx-runtime.js" }
+			File "package.json" { from = "../react/package.json" }
+		}
+	}
+
+	END_SETUP
+ */
+
+
+// XPECT noerrors -->
+// XPECT nowarnings -->
+const MyDiv1 = <div children={"Hello World"}></div>;
+MyDiv1;
+
+// XPECT warnings --> "Attribute 'children' will be overwritten by jsx child elements." at "children"
+const MyDiv2 = <div children={"Hello World"}>{"Guten Tag"}</div>;
+MyDiv2;
+
+// XPECT warnings --> "Attribute 'children' will be overwritten by jsx child elements." at "children"
+const MyDiv3 = <div children={"Hello World"}><h2></h2></div>;
+MyDiv3;
+
+
+
+
+/* XPECT compileResult ---
+// Generated by N4JS transpiler; for copyright see original N4JS source file.
+
+import 'n4js-runtime'
+import {jsx as $jsx} from 'react/jsx-runtime.js'
+
+const MyDiv1 = $jsx('div', {
+	children: "Hello World"
+});
+MyDiv1;
+const MyDiv2 = $jsx('div', Object.assign({
+	children: "Hello World"
+}, {
+	children: "Guten Tag"
+}));
+MyDiv2;
+const MyDiv3 = $jsx('div', Object.assign({
+	children: "Hello World"
+}, {
+	children: $jsx('h2', {})
+}));
+MyDiv3;
+//# sourceMappingURL=jsx_transpile_children.map
+--- */