dont generate code for non-updating if block - fixes #3447

src/compiler/compile/render_dom/wrappers/IfBlock.ts

@@ -441,6 +441,7 @@ export default class IfBlockWrapper extends Wrapper {
 			`if (${name}) ${name}.m(${initial_mount_node}, ${anchor_node});`
 		);
 
+		if (!branch.dependencies || branch.dependencies.length > 0) {
 			const update_mount_node = this.get_update_mount_node(anchor);
 
 			const enter = dynamic
@@ -461,12 +462,10 @@ export default class IfBlockWrapper extends Wrapper {
 						${name}.c();
 						${has_transitions && `@transition_in(${name}, 1);`}
 						${name}.m(${update_mount_node}, ${anchor});
-				${has_transitions && `} else {
+					} ${has_transitions && `else @transition_in(${name}, 1);`}
-					@transition_in(${name}, 1);`}
-				}
 				`;
 
-		if (branch.snippet && branch.dependencies.length) {
+			if (branch.snippet) {
 				block.builders.update.add_block(`if (${branch.dependencies.map(n => `changed.${n}`).join(' || ')}) ${branch.condition} = ${branch.snippet}`);
 			}
 
@@ -494,6 +493,7 @@ export default class IfBlockWrapper extends Wrapper {
 					}
 				`);
 			}
+		}
 
 		block.builders.destroy.add_line(`${if_name}${name}.d(${detaching});`);
 	}

test/js/samples/if-block-complex/expected.js

@@ -49,19 +49,7 @@ function create_fragment(ctx) {
 			insert(target, if_block_anchor, anchor);
 		},
 
-		p(changed, ctx) {
+		p: noop,
-			if (show_if) {
-				if (!if_block) {
-					if_block = create_if_block(ctx);
-					if_block.c();
-					if_block.m(if_block_anchor.parentNode, if_block_anchor);
-				}
-			} else if (if_block) {
-				if_block.d(1);
-				if_block = null;
-			}
-		},
-
 		i: noop,
 		o: noop,