From 01eb3c12e9711bd1efb5f1e8ee48a34dd315b380 Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Mon, 25 Nov 2019 10:04:00 -0500
Subject: [PATCH] feat(transition): warn non-animatable component root node

---
 packages/runtime-core/src/componentRenderUtils.ts | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/packages/runtime-core/src/componentRenderUtils.ts b/packages/runtime-core/src/componentRenderUtils.ts
index d42982d58..7663677c6 100644
--- a/packages/runtime-core/src/componentRenderUtils.ts
+++ b/packages/runtime-core/src/componentRenderUtils.ts
@@ -88,7 +88,16 @@ export function renderComponentRoot(
 
     // inherit transition data
     if (vnode.transition != null) {
-      // TODO warn if component has transition data but root is a fragment
+      if (
+        __DEV__ &&
+        !(result.shapeFlag & ShapeFlags.COMPONENT) &&
+        !(result.shapeFlag & ShapeFlags.ELEMENT)
+      ) {
+        warn(
+          `Component inside <Transition> renders non-element root node ` +
+            `that cannot be animated.`
+        )
+      }
       result.transition = vnode.transition
     }
   } catch (err) {