fix: allow mixed casing of caption/summary

Closes #771

Author: Marcy Sutton

lib/checks/tables/same-caption-summary.js

@@ -1,2 +1,4 @@
-// passing node.caption to accessibleText instead of using the logic in accessibleTextVirtual on virtualNode
-return !!(node.summary && node.caption) && node.summary === axe.commons.text.accessibleText(node.caption);
+// passing node.caption to accessibleText instead of using
+// the logic in accessibleTextVirtual on virtualNode
+return !!(node.summary && node.caption) &&
+	node.summary.toLowerCase() === axe.commons.text.accessibleText(node.caption).toLowerCase();

test/checks/tables/same-caption-summary.js

@@ -42,6 +42,20 @@ describe('same-caption-summary', function () {
 		assert.isTrue(checks['same-caption-summary'].evaluate.apply(checkContext, params));
 	});
 
+	it('should return true if summary and caption are the same with mixed casing', function () {
+		var params = checkSetup('<table summary="My Table" id="target">' +
+			'<caption> my table </caption>' +
+			'<thead>' +
+				'<tr><th scope="col">Head</th></tr>' +
+			'</thead>' +
+			'<tbody>' +
+				'<tr><td>Data</td></tr>' +
+			'</tbody>' +
+		'</table>');
+
+		assert.isTrue(checks['same-caption-summary'].evaluate.apply(checkContext, params));
+	});
+
 	(shadowSupport.v1 ? it : xit)('should match slotted caption elements', function () {
 		var params = shadowCheckSetup(
 			'<div>' +