read tag option from <svelte:meta>

src/compile/Component.ts

@@ -227,8 +227,17 @@ export default class Component {
 
 		if (options.customElement === true) {
 			this.customElement = {
-				tag: this.tag,
-				props: this.props
+				tag: null,
+				props: [] // TODO!!!
+			};
+
+			// find <svelte:meta> tag
+			const meta = this.ast.html.children.find(node => node.name === 'svelte:meta');
+			if (meta) {
+				const tag_attribute = meta.attributes.find(a => a.name === 'tag');
+				if (tag_attribute) {
+					this.customElement.tag = tag_attribute.value[0].data;
+				}
 			}
 		} else {
 			this.customElement = options.customElement;

src/compile/nodes/Meta.ts

@@ -0,0 +1,6 @@
+import Node from './shared/Node';
+
+export default class Meta extends Node {
+	type: 'Meta';
+	data: string;
+}

src/compile/nodes/shared/mapChildren.ts

@@ -6,6 +6,7 @@ import Element from '../Element';
 import Head from '../Head';
 import IfBlock from '../IfBlock';
 import InlineComponent from '../InlineComponent';
+import Meta from '../Meta';
 import MustacheTag from '../MustacheTag';
 import RawMustacheTag from '../RawMustacheTag';
 import DebugTag from '../DebugTag';
@@ -25,6 +26,7 @@ function getConstructor(type): typeof Node {
 		case 'Head': return Head;
 		case 'IfBlock': return IfBlock;
 		case 'InlineComponent': return InlineComponent;
+		case 'Meta': return Meta;
 		case 'MustacheTag': return MustacheTag;
 		case 'RawMustacheTag': return RawMustacheTag;
 		case 'DebugTag': return DebugTag;