From 6354c66890a1af8d3c01684089fbddd1359307eb Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Mon, 18 Mar 2019 10:52:08 -0400
Subject: [PATCH] fix renamed instance exports (#2253)

---
 src/compile/Component.ts                               |  4 ++--
 src/compile/render-dom/index.ts                        |  2 +-
 .../samples/renamed-instance-exports/_config.js        | 10 ++++++++++
 .../samples/renamed-instance-exports/main.svelte       |  5 +++++
 4 files changed, 18 insertions(+), 3 deletions(-)
 create mode 100644 test/runtime/samples/renamed-instance-exports/_config.js
 create mode 100644 test/runtime/samples/renamed-instance-exports/main.svelte

diff --git a/src/compile/Component.ts b/src/compile/Component.ts
index f7c1c7dc5d..51746fb067 100644
--- a/src/compile/Component.ts
+++ b/src/compile/Component.ts
@@ -834,8 +834,8 @@ export default class Component {
 									current_group.declarators.push(declarator);
 								}
 
-								if (variable.name !== variable.export_name) {
-									code.prependRight(declarator.id.start, `${variable.export_name}:`)
+								if (variable.writable && variable.name !== variable.export_name) {
+									code.prependRight(declarator.id.start, `${variable.export_name}: `)
 								}
 
 								if (next) {
diff --git a/src/compile/render-dom/index.ts b/src/compile/render-dom/index.ts
index 5b37ac031c..6678b21872 100644
--- a/src/compile/render-dom/index.ts
+++ b/src/compile/render-dom/index.ts
@@ -114,7 +114,7 @@ export default function dom(
 			if (component.component_options.accessors) {
 				body.push(deindent`
 					set ${x.export_name}(${x.name}) {
-						this.$set({ ${x.name} });
+						this.$set({ ${x.name === x.export_name ? x.name : `${x.export_name}: ${x.name}`} });
 						@flush();
 					}
 				`);
diff --git a/test/runtime/samples/renamed-instance-exports/_config.js b/test/runtime/samples/renamed-instance-exports/_config.js
new file mode 100644
index 0000000000..965df3b4f3
--- /dev/null
+++ b/test/runtime/samples/renamed-instance-exports/_config.js
@@ -0,0 +1,10 @@
+export default {
+	test({ assert, component }) {
+		assert.equal(component.bar1, 42);
+		assert.equal(component.bar2, 42);
+		component.bar1 = 100;
+		component.bar2 = 100;
+		assert.equal(component.bar1, 42);
+		assert.equal(component.bar2, 100);
+	}
+};
diff --git a/test/runtime/samples/renamed-instance-exports/main.svelte b/test/runtime/samples/renamed-instance-exports/main.svelte
new file mode 100644
index 0000000000..7c991f56c4
--- /dev/null
+++ b/test/runtime/samples/renamed-instance-exports/main.svelte
@@ -0,0 +1,5 @@
+<script>
+	const foo1 = 42;
+	let foo2 = 42;
+	export { foo1 as bar1, foo2 as bar2 };
+</script>