Fix incorrect handling elemental selector without a namespace

src/__fixtures__/tests.ts

@@ -843,6 +843,19 @@ export const tests: [
         ],
         "star tag namespace",
     ],
+    [
+        "|bar",
+        [
+            [
+                {
+                    name: "bar",
+                    type: "tag",
+                    namespace: "",
+                },
+            ],
+        ],
+        "without namespace",
+    ],
     [
         "*|*",
         [
@@ -870,6 +883,21 @@ export const tests: [
         ],
         "basic attribute namespace, existential",
     ],
+    [
+        "[|bar]",
+        [
+            [
+                {
+                    action: "exists",
+                    name: "bar",
+                    type: "attribute",
+                    namespace: "",
+                    value: "",
+                },
+            ],
+        ],
+        "without namespace, existential",
+    ],
     [
         "[foo|bar='baz' i]",
         [

src/parse.ts

@@ -391,6 +391,10 @@ function parseSelector(
                     selectorIndex += 1;
                     name = "*";
                 } else if (reName.test(selector.slice(selectorIndex))) {
+                    if (selector.charAt(selectorIndex) === "|") {
+                        namespace = "";
+                        selectorIndex += 1;
+                    }
                     name = getName(0);
                 } else {
                     /*

src/stringify.ts

@@ -106,7 +106,7 @@ function getNamespacedName(token: {
 }
 
 function getNamespace(namespace: string | null): string {
-    return namespace
+    return namespace !== null
         ? `${namespace === "*" ? "*" : escapeName(namespace)}|`
         : "";
 }