From eb04e603952512106e7a41fc49bbd31aafd273f6 Mon Sep 17 00:00:00 2001
From: Thibaud Colas <thibaudcolas@gmail.com>
Date: Sat, 17 Sep 2022 16:29:13 +0100
Subject: [PATCH] Change html-lang-valid selector so the rule only applies when
 attrs have a value. Fix #3624

---
 lib/rules/html-lang-valid.json                    |  2 +-
 test/integration/virtual-rules/html-lang-valid.js | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/lib/rules/html-lang-valid.json b/lib/rules/html-lang-valid.json
index 19fd4c01c9..5cf81f4325 100644
--- a/lib/rules/html-lang-valid.json
+++ b/lib/rules/html-lang-valid.json
@@ -1,6 +1,6 @@
 {
   "id": "html-lang-valid",
-  "selector": "html[lang], html[xml\\:lang]",
+  "selector": "html[lang]:not([lang=\"\"]), html[xml\\:lang]:not([xml\\:lang=\"\"])",
   "tags": ["cat.language", "wcag2a", "wcag311", "ACT"],
   "actIds": ["bf051a"],
   "metadata": {
diff --git a/test/integration/virtual-rules/html-lang-valid.js b/test/integration/virtual-rules/html-lang-valid.js
index d89d410ca6..8e7675a7a2 100644
--- a/test/integration/virtual-rules/html-lang-valid.js
+++ b/test/integration/virtual-rules/html-lang-valid.js
@@ -6,6 +6,21 @@ describe('html-lang-valid virtual-rule', function() {
       attributes: {}
     });
 
+    assert.lengthOf(results.inapplicable, 1);
+    assert.lengthOf(results.passes, 0);
+    assert.lengthOf(results.violations, 0);
+    assert.lengthOf(results.incomplete, 0);
+  });
+
+	it('is inapplicable with empty lang or xml:lang', function() {
+    // Error caught by html-has-lang instead
+    var results = axe.runVirtualRule('html-lang-valid', {
+      nodeName: 'html',
+      attributes: {
+        'lang': '',
+      }
+    });
+
     assert.lengthOf(results.inapplicable, 1);
     assert.lengthOf(results.passes, 0);
     assert.lengthOf(results.violations, 0);