comment fix + test case

packages/svelte/src/compiler/phases/3-transform/utils.js

@@ -222,7 +222,7 @@ export function infer_namespace(namespace, parent, nodes, path) {
 					only_svg = false;
 					break;
 				}
-			} else if (node.type !== 'Text' || node.data.trim() !== '') {
+			} else if (node.type !== 'Comment' && (node.type !== 'Text' || node.data.trim() !== '')) {
 				only_svg = false;
 			}
 		}

packages/svelte/tests/runtime-runes/samples/svg-namespace-infer/Wrapper.svelte

@@ -0,0 +1,13 @@
+<text x="0" y=14>outside</text>
+
+{#if true}
+  <text x="0" y="26">true</text>
+{:else}
+  <text x="0" y="26">false</text>
+{/if}
+
+{#each  Array(3).fill(0) as item, idx}
+  <text x={idx * 10} y={42}>{idx}</text>
+{/each}
+
+<!-- comment should not set infer html namespace -->

packages/svelte/tests/runtime-runes/samples/svg-namespace-infer/_config.js

@@ -0,0 +1,26 @@
+import { test, ok } from '../../test';
+
+export default test({
+	html: `
+	<svg>
+		<text x="0" y="14">outside</text>
+		<text x="0" y="26">true</text>
+		<text x="0" y="42">0</text>
+		<text x="10" y="42">1</text>
+		<text x="20" y="42">2</text>
+	</svg>
+`,
+	test({ assert, target }) {
+		const svg = target.querySelector('svg');
+		ok(svg);
+
+		assert.equal(svg.namespaceURI, 'http://www.w3.org/2000/svg');
+
+		const text_elements = target.querySelectorAll('text');
+
+		assert.equal(text_elements.length, 5);
+
+		for (const { namespaceURI } of text_elements)
+			assert.equal(namespaceURI, 'http://www.w3.org/2000/svg');
+	}
+});

packages/svelte/tests/runtime-runes/samples/svg-namespace-infer/main.svelte

@@ -0,0 +1,7 @@
+<script>
+  import Wrapper from "./Wrapper.svelte";
+</script>
+
+<svg>
+  <Wrapper />
+</svg>