Check if data is a function

src/validate/js/propValidators/data.ts

@@ -1,14 +1,12 @@
 import { Validator } from '../../';
 import { Node } from '../../../interfaces';
 
-const disallowed = new Set(['Literal', 'ObjectExpression', 'ArrayExpression']);
+const allowed = new Set(['FunctionExpression', 'ArrowFunctionExpression'])
 
 export default function data(validator: Validator, prop: Node) {
 	while (prop.type === 'ParenthesizedExpression') prop = prop.expression;
 
-	// TODO should we disallow references and expressions as well?
+	if (!allowed.has(prop.value.type)) {
-
-	if (disallowed.has(prop.value.type)) {
 		validator.error(`'data' must be a function`, prop.value.start);
 	}
 }

test/validator/samples/properties-data-no-call-expression/errors.json

@@ -0,0 +1,8 @@
+[{
+	"message": "'data' must be a function",
+	"loc": {
+		"line": 10,
+		"column": 8
+	},
+	"pos": 131
+}]

test/validator/samples/properties-data-no-call-expression/input.html

@@ -0,0 +1,12 @@
+<div></div>
+
+<script>
+	function data (foo) {
+		return function () {
+			return { foo, bar: 'baz' }
+		}
+	}
+	export default {
+		data: data('hello')
+	};
+</script>

test/validator/samples/properties-data-no-references/errors.json

@@ -0,0 +1,8 @@
+[{
+	"message": "'data' must be a function",
+	"loc": {
+		"line": 6,
+		"column": 2
+	},
+	"pos": 76
+}]

test/validator/samples/properties-data-no-references/input.html

@@ -0,0 +1,8 @@
+<div></div>
+
+<script>
+	const data = () => ({ foo: 42 })
+	export default {
+		data
+	};
+</script>