fix figcaption a11y warning - fixes #996

src/validate/html/a11y.ts

@@ -159,8 +159,15 @@ export default function a11y(
 			if (parent.name !== 'figure') {
 				validator.warn(`A11y: <figcaption> must be an immediate child of <figure>`, node.start);
 			} else {
-				const index = parent.children.indexOf(node);
-				if (index !== 0 && index !== parent.children.length - 1) {
+				const children = parent.children.filter(node => {
+					if (node.type === 'Comment') return false;
+					if (node.type === 'Text') return /\S/.test(node.data);
+					return true;
+				});
+
+				const index = children.indexOf(node);
+
+				if (index !== 0 && index !== children.length - 1) {
 					validator.warn(`A11y: <figcaption> must be first or last child of <figure>`, node.start);
 				}
 			}

test/validator/samples/a11y-figcaption-right-place/input.html

@@ -0,0 +1,7 @@
+<figure>
+	<img src='foo.jpg' alt='a picture of a foo'>
+
+	<figcaption>
+		a foo in its natural habitat
+	</figcaption>
+</figure>

test/validator/samples/a11y-figcaption-right-place/warnings.json

@@ -0,0 +1 @@
+[]