From 427aa7eb847936df5b2c380edc6ef6935a0b2289 Mon Sep 17 00:00:00 2001
From: Rich Harris <richard.a.harris@gmail.com>
Date: Thu, 23 Nov 2017 09:29:19 -0500
Subject: [PATCH] test unknown format, and improve error message

---
 src/generators/shared/utils/wrapModule.ts |  3 ++-
 src/{validate => }/utils/list.ts          |  0
 src/validate/html/validateEventHandler.ts |  2 +-
 src/validate/html/validateWindow.ts       |  2 +-
 test/formats/index.js                     | 10 ++++++++++
 5 files changed, 14 insertions(+), 3 deletions(-)
 rename src/{validate => }/utils/list.ts (100%)

diff --git a/src/generators/shared/utils/wrapModule.ts b/src/generators/shared/utils/wrapModule.ts
index 3492ba0a27..7e55996aa4 100644
--- a/src/generators/shared/utils/wrapModule.ts
+++ b/src/generators/shared/utils/wrapModule.ts
@@ -1,4 +1,5 @@
 import deindent from '../../../utils/deindent';
+import list from '../../../utils/list';
 import { CompileOptions, ModuleFormat, Node } from '../../../interfaces';
 
 interface Dependency {
@@ -65,7 +66,7 @@ export default function wrapModule(
 	if (format === 'umd') return umd(code, name, options, banner, dependencies);
 	if (format === 'eval') return expr(code, name, options, banner, dependencies);
 
-	throw new Error(`Not implemented: ${format}`);
+	throw new Error(`options.format is invalid (must be ${list(Object.keys(wrappers))})`);
 }
 
 function es(
diff --git a/src/validate/utils/list.ts b/src/utils/list.ts
similarity index 100%
rename from src/validate/utils/list.ts
rename to src/utils/list.ts
diff --git a/src/validate/html/validateEventHandler.ts b/src/validate/html/validateEventHandler.ts
index e2b6e405d7..2339f801d9 100644
--- a/src/validate/html/validateEventHandler.ts
+++ b/src/validate/html/validateEventHandler.ts
@@ -1,5 +1,5 @@
 import flattenReference from '../../utils/flattenReference';
-import list from '../utils/list';
+import list from '../../utils/list';
 import { Validator } from '../index';
 import validCalleeObjects from '../../utils/validCalleeObjects';
 import { Node } from '../../interfaces';
diff --git a/src/validate/html/validateWindow.ts b/src/validate/html/validateWindow.ts
index 88f41ff5eb..3cfc80f6bc 100644
--- a/src/validate/html/validateWindow.ts
+++ b/src/validate/html/validateWindow.ts
@@ -1,6 +1,6 @@
 import flattenReference from '../../utils/flattenReference';
 import fuzzymatch from '../utils/fuzzymatch';
-import list from '../utils/list';
+import list from '../../utils/list';
 import validateEventHandler from './validateEventHandler';
 import { Validator } from '../index';
 import { Node } from '../../interfaces';
diff --git a/test/formats/index.js b/test/formats/index.js
index b69bde817a..e4f3b41271 100644
--- a/test/formats/index.js
+++ b/test/formats/index.js
@@ -218,4 +218,14 @@ describe("formats", () => {
 			return testEval(code, "Foo", { answer: 42 }, `<div>42</div>`);
 		});
 	});
+
+	describe('unknown format', () => {
+		it('throws an error', () => {
+			assert.throws(() => {
+				svelte.compile('', {
+					format: 'nope'
+				});
+			}, /options.format is invalid \(must be es, amd, cjs, iife, umd or eval\)/);
+		});
+	});
 });