[feat] skip custom element check if <svelte:element> uses under svg (#7869)

* add test

* skip custom element check if svelte element uses under svg

src/compiler/compile/render_dom/wrappers/Element/index.ts

@@ -806,7 +806,9 @@ export default class ElementWrapper extends Wrapper {
 		if (this.node.is_dynamic_element) {
 			// call attribute bindings for custom element if tag is custom element
 			const tag = this.node.tag_expr.manipulate(block);
-			const attr_update = b`
+			const attr_update = this.node.namespace === namespaces.svg
+				? b`${fn}(${this.var}, ${data});`
+				: b`
 					if (/-/.test(${tag})) {
 						@set_custom_element_data_map(${this.var}, ${data});
 					} else {

test/js/samples/svelte-element-svg/expected.js

@@ -48,8 +48,10 @@ function create_dynamic_element(ctx) {
 			append(svelte_element1, svelte_element0);
 		},
 		p(ctx, dirty) {
-			set_svg_attributes(svelte_element0, svelte_element0_data = get_spread_update(svelte_element0_levels, [{ xmlns: "http://www.w3.org/2000/svg" }]));
+			svelte_element0_data = get_spread_update(svelte_element0_levels, [{ xmlns: "http://www.w3.org/2000/svg" }]);
-			set_svg_attributes(svelte_element1, svelte_element1_data = get_spread_update(svelte_element1_levels, [{ xmlns: "http://www.w3.org/2000/svg" }]));
+			set_svg_attributes(svelte_element0, svelte_element0_data);
+			svelte_element1_data = get_spread_update(svelte_element1_levels, [{ xmlns: "http://www.w3.org/2000/svg" }]);
+			set_svg_attributes(svelte_element1, svelte_element1_data);
 		},
 		d(detaching) {
 			if (detaching) detach(svelte_element1);

test/runtime/samples/dynamic-element-svg/_config.js

@@ -0,0 +1,10 @@
+export default {
+	html: '<svg xmlns="http://www.w3.org/2000/svg"><path xmlns="http://www.w3.org/2000/svg"></path></svg>',
+
+	test({ assert, target }) {
+		const svg = target.querySelector('svg');
+		const rect = target.querySelector('path');
+		assert.equal(svg.namespaceURI, 'http://www.w3.org/2000/svg');
+		assert.equal(rect.namespaceURI, 'http://www.w3.org/2000/svg');
+	}
+};

test/runtime/samples/dynamic-element-svg/main.svelte

@@ -0,0 +1,3 @@
+<svelte:element this="svg" xmlns="http://www.w3.org/2000/svg">
+    <svelte:element this="path" xmlns="http://www.w3.org/2000/svg"></svelte:element>
+</svelte:element>