From cb92f3028e360b2ce745a1b879a1c8e42882e29d Mon Sep 17 00:00:00 2001
From: Rich Harris <richard.a.harris@gmail.com>
Date: Tue, 29 Aug 2017 08:09:41 -0400
Subject: [PATCH] error if component has transition (fixes #791)

---
 src/validate/html/validateElement.ts              |  4 ++++
 .../samples/transition-on-component/errors.json   |  8 ++++++++
 .../samples/transition-on-component/input.html    | 15 +++++++++++++++
 3 files changed, 27 insertions(+)
 create mode 100644 test/validator/samples/transition-on-component/errors.json
 create mode 100644 test/validator/samples/transition-on-component/input.html

diff --git a/src/validate/html/validateElement.ts b/src/validate/html/validateElement.ts
index ce412382c651..3641280f191f 100644
--- a/src/validate/html/validateElement.ts
+++ b/src/validate/html/validateElement.ts
@@ -116,6 +116,10 @@ export default function validateElement(validator: Validator, node: Node, refs:
 		} else if (attribute.type === 'EventHandler') {
 			validateEventHandler(validator, attribute, refCallees);
 		} else if (attribute.type === 'Transition') {
+			if (isComponent) {
+				validator.error(`Transitions can only be applied to DOM elements, not components`, attribute.start);
+			}
+
 			const bidi = attribute.intro && attribute.outro;
 
 			if (hasTransition) {
diff --git a/test/validator/samples/transition-on-component/errors.json b/test/validator/samples/transition-on-component/errors.json
new file mode 100644
index 000000000000..d18125c8c297
--- /dev/null
+++ b/test/validator/samples/transition-on-component/errors.json
@@ -0,0 +1,8 @@
+[{
+	"message": "Transitions can only be applied to DOM elements, not components",
+	"loc": {
+		"line": 1,
+		"column": 8
+	},
+	"pos": 8
+}]
\ No newline at end of file
diff --git a/test/validator/samples/transition-on-component/input.html b/test/validator/samples/transition-on-component/input.html
new file mode 100644
index 000000000000..c5ada08ece88
--- /dev/null
+++ b/test/validator/samples/transition-on-component/input.html
@@ -0,0 +1,15 @@
+<Widget in:foo/>
+
+<script>
+	import Widget from './Widget.html';
+
+	export default {
+		components: {
+			Widget
+		},
+
+		transitions: {
+			foo() {}
+		}
+	};
+</script>
\ No newline at end of file