From 40d75f4968ddf1ebc140f26b1dfd86e8d9ee5495 Mon Sep 17 00:00:00 2001
From: Tan Li Hau <lhtan93@gmail.com>
Date: Thu, 24 Sep 2020 19:08:41 +0800
Subject: [PATCH 1/2] remove undefined warning for action object

---
 src/compiler/compile/nodes/Action.ts            |  5 +++--
 .../samples/action-object/input.svelte          | 11 +++++++++++
 .../samples/action-object/warnings.json         | 17 +++++++++++++++++
 3 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 test/validator/samples/action-object/input.svelte
 create mode 100644 test/validator/samples/action-object/warnings.json

diff --git a/src/compiler/compile/nodes/Action.ts b/src/compiler/compile/nodes/Action.ts
index 86aefa0cedac..dc6f080b718c 100644
--- a/src/compiler/compile/nodes/Action.ts
+++ b/src/compiler/compile/nodes/Action.ts
@@ -11,10 +11,11 @@ export default class Action extends Node {
 	constructor(component: Component, parent, scope, info) {
 		super(component, parent, scope, info);
 
-		component.warn_if_undefined(info.name, info, scope);
+		const object = info.name.split('.')[0];
+		component.warn_if_undefined(object, info, scope);
 
 		this.name = info.name;
-		component.add_reference(info.name.split('.')[0]);
+		component.add_reference(object);
 
 		this.expression = info.expression
 			? new Expression(component, this, scope, info.expression)
diff --git a/test/validator/samples/action-object/input.svelte b/test/validator/samples/action-object/input.svelte
new file mode 100644
index 000000000000..e0962fa594ac
--- /dev/null
+++ b/test/validator/samples/action-object/input.svelte
@@ -0,0 +1,11 @@
+<script>
+	const obj = {
+		foo : "bar",
+		action(element, { leet }) {
+			element.foo = this.foo + leet;
+		},
+	}
+</script>
+
+<button use:obj.action={{ leet: 1337 }}>action</button>
+<button use:foo.action={{ leet: 1337 }}>action</button>
\ No newline at end of file
diff --git a/test/validator/samples/action-object/warnings.json b/test/validator/samples/action-object/warnings.json
new file mode 100644
index 000000000000..e1ccbb55a28a
--- /dev/null
+++ b/test/validator/samples/action-object/warnings.json
@@ -0,0 +1,17 @@
+[
+	{
+		"code": "missing-declaration",
+		"end": {
+			"character": 217,
+			"column": 39,
+			"line": 11
+		},
+		"message": "'foo' is not defined",
+		"pos": 186,
+		"start": {
+			"character": 186,
+			"column": 8,
+			"line": 11
+		}
+	}
+]

From ab1ddf252f627f5dae6dae9c206803f446dd0723 Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Thu, 24 Sep 2020 09:30:46 -0400
Subject: [PATCH 2/2] update changelog

---
 CHANGELOG.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3347052e7560..69edc48b0e3a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Svelte changelog
 
+## Unreleased
+
+* Fix erroneous `missing-declaration` warning with `use:obj.method` ([#5451](https://github.com/sveltejs/svelte/issues/5451))
+
 ## 3.26.0
 
 * Support `use:obj.method` as actions ([#3935](https://github.com/sveltejs/svelte/issues/3935))