mount await blocks with siblings (#974), and unmount correctly (#975)

src/generators/dom/visitors/AwaitBlock.ts

@@ -67,7 +67,7 @@ export default function visitAwaitBlock(
 				${old_block}.u();
 				${old_block}.d();
 				${await_block}.c();
-				${await_block}.m(${anchor}.parentNode, ${anchor});
+				${await_block}.m(${state.parentNode || `${anchor}.parentNode`}, ${anchor});
 			}
 		}
 
@@ -142,6 +142,10 @@ export default function visitAwaitBlock(
 		`);
 	}
 
+	block.builders.unmount.addBlock(deindent`
+		${await_block}.u();
+	`);
+
 	block.builders.destroy.addBlock(deindent`
 		${await_token} = null;
 		${await_block}.d();

test/runtime/samples/await-then-catch-if/_config.js

@@ -1,6 +1,6 @@
 let fulfil;
 
-let thePromise = new Promise(f => {
+const thePromise = new Promise(f => {
 	fulfil = f;
 });
 
@@ -35,9 +35,11 @@ export default {
 					show: true
 				});
 
+				return thePromise.then(() => {
 					assert.htmlEqual(target.innerHTML, `
 						<p>the value is 42</p>
 					`);
 				});
+			});
 	}
 };