add ssr for group bindings

src/compiler/compile/render_ssr/handlers/Element.ts

@@ -110,7 +110,16 @@ export default function(node: Element, renderer: Renderer, options: RenderOption
 		}
 
 		if (name === 'group') {
-			// TODO server-render group bindings
+			const value_attribute = node.attributes.find(({ name }) => name === 'value');
+			if (value_attribute && value_attribute.chunks.length === 1) {
+				const value = get_attribute_value(value_attribute);
+				const bound = expression.node;
+				renderer.add_expression(x`
+					${value} === ${bound} || Array.isArray(${bound}) && ${bound}.includes(${value})
+						? @add_attribute("checked", true, 1)
+						: ""
+				`);
+			}
 		} else if (contenteditable && (name === 'textContent' || name === 'innerHTML')) {
 			node_contents = expression.node;
 

test/server-side-rendering/samples/bindings-group/_expected.html

@@ -0,0 +1,5 @@
+<div>Cheese</div>
+<input type="radio" value="Plain" checked>
+<input type="radio" value="Whole wheat">
+<input type="checkbox" value="Beans">
+<input type="checkbox" value="Cheese" checked>

test/server-side-rendering/samples/bindings-group/main.svelte

@@ -0,0 +1,12 @@
+<script>
+	let tortilla = 'Plain';
+	let fillings = ['Cheese'];
+</script>
+
+<div>{fillings.toString()}</div>
+
+<input type="radio" bind:group={tortilla} value="Plain">
+<input type="radio" bind:group={tortilla} value="Whole wheat">
+
+<input type="checkbox" bind:group={fillings} value="Beans">
+<input type="checkbox" bind:group={fillings} value="Cheese">