From 0cf9861e1f6dbe52e1d9ca8d1d43e1eca015e0aa Mon Sep 17 00:00:00 2001
From: Tan Li Hau <lhtan93@gmail.com>
Date: Tue, 3 Mar 2020 15:50:39 +0800
Subject: [PATCH 1/7] warn if passing slot not defined into Component

---
 src/compiler/compile/render_dom/index.ts                 | 3 ++-
 src/runtime/internal/dev.ts                              | 8 ++++++++
 .../runtime/samples/component-slot-warning/Nested.svelte | 1 +
 test/runtime/samples/component-slot-warning/_config.js   | 9 +++++++++
 test/runtime/samples/component-slot-warning/main.svelte  | 7 +++++++
 5 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 test/runtime/samples/component-slot-warning/Nested.svelte
 create mode 100644 test/runtime/samples/component-slot-warning/_config.js
 create mode 100644 test/runtime/samples/component-slot-warning/main.svelte

diff --git a/src/compiler/compile/render_dom/index.ts b/src/compiler/compile/render_dom/index.ts
index d6da6142768c..179115b5b248 100644
--- a/src/compiler/compile/render_dom/index.ts
+++ b/src/compiler/compile/render_dom/index.ts
@@ -412,7 +412,8 @@ export default function dom(
 
 				${unknown_props_check}
 
-				${component.slots.size ? b`let { $$slots = {}, $$scope } = $$props;` : null}
+				${component.slots.size || component.compile_options.dev ? b`let { $$slots = {}, $$scope } = $$props;` : null}
+				${component.compile_options.dev && b`@validate_slot($$slots, [${Array.from(component.slots.keys()).map(key => `"${key}"`).join(',')}]);`}
 
 				${renderer.binding_groups.length > 0 && b`const $$binding_groups = [${renderer.binding_groups.map(_ => x`[]`)}];`}
 
diff --git a/src/runtime/internal/dev.ts b/src/runtime/internal/dev.ts
index 8aefc88ba7b0..865f23ce1165 100644
--- a/src/runtime/internal/dev.ts
+++ b/src/runtime/internal/dev.ts
@@ -89,6 +89,14 @@ export function validate_each_argument(arg) {
 	}
 }
 
+export function validate_slot(slot, keys) {
+	keys = new Set(keys);
+	for (const slot_key of Object.keys(slot)) {
+		if (!keys.has(slot_key)) {
+			console.warn(`Received unexpected slot named "${slot_key}"`);
+		}
+	}
+}
 
 type Props = Record<string, any>;
 export interface SvelteComponentDev {
diff --git a/test/runtime/samples/component-slot-warning/Nested.svelte b/test/runtime/samples/component-slot-warning/Nested.svelte
new file mode 100644
index 000000000000..c6f086d96c19
--- /dev/null
+++ b/test/runtime/samples/component-slot-warning/Nested.svelte
@@ -0,0 +1 @@
+<slot name="slot2"></slot>
\ No newline at end of file
diff --git a/test/runtime/samples/component-slot-warning/_config.js b/test/runtime/samples/component-slot-warning/_config.js
new file mode 100644
index 000000000000..e652d8e4fd17
--- /dev/null
+++ b/test/runtime/samples/component-slot-warning/_config.js
@@ -0,0 +1,9 @@
+export default {
+	compileOptions: {
+		dev: true
+	},
+	warnings: [
+		'Received unexpected slot named "default"',
+		'Received unexpected slot named "slot1"'
+	]
+};
diff --git a/test/runtime/samples/component-slot-warning/main.svelte b/test/runtime/samples/component-slot-warning/main.svelte
new file mode 100644
index 000000000000..c29ef3e85be2
--- /dev/null
+++ b/test/runtime/samples/component-slot-warning/main.svelte
@@ -0,0 +1,7 @@
+<script>
+	import Nested from "./Nested.svelte";
+</script>
+<Nested>
+	<input slot="slot1">
+	<input slot="slot2">
+</Nested>

From 6931a0c1cf44d92f73f61a3b1e4ae045363db25e Mon Sep 17 00:00:00 2001
From: Tan Li Hau <lhtan93@gmail.com>
Date: Tue, 3 Mar 2020 15:56:10 +0800
Subject: [PATCH 2/7] update js code snapshot

---
 test/js/samples/capture-inject-state/expected.js          | 4 ++++
 test/js/samples/debug-empty/expected.js                   | 6 +++++-
 test/js/samples/debug-foo-bar-baz-things/expected.js      | 6 +++++-
 test/js/samples/debug-foo/expected.js                     | 6 +++++-
 test/js/samples/debug-hoisted/expected.js                 | 5 ++++-
 test/js/samples/debug-no-dependencies/expected.js         | 5 ++++-
 .../samples/dev-warning-missing-data-computed/expected.js | 6 +++++-
 test/js/samples/loop-protect/expected.js                  | 8 ++++++--
 8 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/test/js/samples/capture-inject-state/expected.js b/test/js/samples/capture-inject-state/expected.js
index 859314556580..017d9868d543 100644
--- a/test/js/samples/capture-inject-state/expected.js
+++ b/test/js/samples/capture-inject-state/expected.js
@@ -14,6 +14,7 @@ import {
 	space,
 	subscribe,
 	text,
+	validate_slot,
 	validate_store
 } from "svelte/internal";
 
@@ -114,6 +115,9 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
+
 	$$self.$set = $$props => {
 		if ("prop" in $$props) $$subscribe_prop($$invalidate(0, prop = $$props.prop));
 		if ("alias" in $$props) $$invalidate(1, realName = $$props.alias);
diff --git a/test/js/samples/debug-empty/expected.js b/test/js/samples/debug-empty/expected.js
index 87d78bd69821..6f16a655eede 100644
--- a/test/js/samples/debug-empty/expected.js
+++ b/test/js/samples/debug-empty/expected.js
@@ -12,7 +12,8 @@ import {
 	safe_not_equal,
 	set_data_dev,
 	space,
-	text
+	text,
+	validate_slot
 } from "svelte/internal";
 
 const file = undefined;
@@ -75,6 +76,9 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
+
 	$$self.$set = $$props => {
 		if ("name" in $$props) $$invalidate(0, name = $$props.name);
 	};
diff --git a/test/js/samples/debug-foo-bar-baz-things/expected.js b/test/js/samples/debug-foo-bar-baz-things/expected.js
index 589c4a783288..4352e981f842 100644
--- a/test/js/samples/debug-foo-bar-baz-things/expected.js
+++ b/test/js/samples/debug-foo-bar-baz-things/expected.js
@@ -14,7 +14,8 @@ import {
 	set_data_dev,
 	space,
 	text,
-	validate_each_argument
+	validate_each_argument,
+	validate_slot
 } from "svelte/internal";
 
 const file = undefined;
@@ -179,6 +180,9 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
+
 	$$self.$set = $$props => {
 		if ("things" in $$props) $$invalidate(0, things = $$props.things);
 		if ("foo" in $$props) $$invalidate(1, foo = $$props.foo);
diff --git a/test/js/samples/debug-foo/expected.js b/test/js/samples/debug-foo/expected.js
index 10129e1b2837..8767eb3acaba 100644
--- a/test/js/samples/debug-foo/expected.js
+++ b/test/js/samples/debug-foo/expected.js
@@ -14,7 +14,8 @@ import {
 	set_data_dev,
 	space,
 	text,
-	validate_each_argument
+	validate_each_argument,
+	validate_slot
 } from "svelte/internal";
 
 const file = undefined;
@@ -171,6 +172,9 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
+
 	$$self.$set = $$props => {
 		if ("things" in $$props) $$invalidate(0, things = $$props.things);
 		if ("foo" in $$props) $$invalidate(1, foo = $$props.foo);
diff --git a/test/js/samples/debug-hoisted/expected.js b/test/js/samples/debug-hoisted/expected.js
index 190ff12c50ee..a774f99b5de3 100644
--- a/test/js/samples/debug-hoisted/expected.js
+++ b/test/js/samples/debug-hoisted/expected.js
@@ -4,7 +4,8 @@ import {
 	dispatch_dev,
 	init,
 	noop,
-	safe_not_equal
+	safe_not_equal,
+	validate_slot
 } from "svelte/internal";
 
 const file = undefined;
@@ -56,6 +57,8 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
 	$$self.$capture_state = () => ({ obj, kobzol });
 
 	$$self.$inject_state = $$props => {
diff --git a/test/js/samples/debug-no-dependencies/expected.js b/test/js/samples/debug-no-dependencies/expected.js
index a097869e747b..3f89b93bc11d 100644
--- a/test/js/samples/debug-no-dependencies/expected.js
+++ b/test/js/samples/debug-no-dependencies/expected.js
@@ -11,7 +11,8 @@ import {
 	safe_not_equal,
 	space,
 	text,
-	validate_each_argument
+	validate_each_argument,
+	validate_slot
 } from "svelte/internal";
 
 const file = undefined;
@@ -141,6 +142,8 @@ function instance($$self, $$props) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
 	return [];
 }
 
diff --git a/test/js/samples/dev-warning-missing-data-computed/expected.js b/test/js/samples/dev-warning-missing-data-computed/expected.js
index 9c28e0406450..658260a080bf 100644
--- a/test/js/samples/dev-warning-missing-data-computed/expected.js
+++ b/test/js/samples/dev-warning-missing-data-computed/expected.js
@@ -12,7 +12,8 @@ import {
 	safe_not_equal,
 	set_data_dev,
 	space,
-	text
+	text,
+	validate_slot
 } from "svelte/internal";
 
 const file = undefined;
@@ -72,6 +73,9 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
+
 	$$self.$set = $$props => {
 		if ("foo" in $$props) $$invalidate(0, foo = $$props.foo);
 	};
diff --git a/test/js/samples/loop-protect/expected.js b/test/js/samples/loop-protect/expected.js
index f433bd61a962..3dfd75911e84 100644
--- a/test/js/samples/loop-protect/expected.js
+++ b/test/js/samples/loop-protect/expected.js
@@ -11,7 +11,8 @@ import {
 	insert_dev,
 	loop_guard,
 	noop,
-	safe_not_equal
+	safe_not_equal,
+	validate_slot
 } from "svelte/internal";
 
 const { console: console_1 } = globals;
@@ -110,6 +111,9 @@ function instance($$self, $$props, $$invalidate) {
 		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console_1.warn(`<Component> was created with unknown prop '${key}'`);
 	});
 
+	let { $$slots = {}, $$scope } = $$props;
+	validate_slot($$slots, []);
+
 	function div_binding($$value) {
 		binding_callbacks[$$value ? "unshift" : "push"](() => {
 			$$invalidate(0, node = $$value);
@@ -161,4 +165,4 @@ class Component extends SvelteComponentDev {
 	}
 }
 
-export default Component;
+export default Component;
\ No newline at end of file

From d9388caa03fdf3f6a3441dc90923b6c5f14d094c Mon Sep 17 00:00:00 2001
From: Tan Li Hau <lhtan93@gmail.com>
Date: Wed, 4 Mar 2020 22:40:06 +0800
Subject: [PATCH 3/7] fix slot fallback not empty

---
 src/compiler/compile/render_dom/Block.ts                      | 4 ++--
 .../compile/render_dom/wrappers/InlineComponent/index.ts      | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/compiler/compile/render_dom/Block.ts b/src/compiler/compile/render_dom/Block.ts
index 62bdc5bdd9af..f9273f7fc93c 100644
--- a/src/compiler/compile/render_dom/Block.ts
+++ b/src/compiler/compile/render_dom/Block.ts
@@ -411,8 +411,8 @@ export default class Block {
 		return body;
 	}
 
-	has_content() {
-		return this.renderer.options.dev ||
+	has_content(ignore_dev?: boolean) {
+		return (!ignore_dev && this.renderer.options.dev) ||
 			this.first ||
 			this.event_listeners.length > 0 ||
 			this.chunks.intro.length > 0 ||
diff --git a/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts b/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts
index 8c8bd706962e..660e4831a2d5 100644
--- a/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts
+++ b/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts
@@ -154,7 +154,7 @@ export default class InlineComponentWrapper extends Wrapper {
 
 		// removing empty slot
 		for (const slot of this.slots.keys()) {
-			if (!this.slots.get(slot).block.has_content()) {
+			if (!this.slots.get(slot).block.has_content(true)) {
 				this.slots.delete(slot);
 			}
 		}

From a31253de4eb1d8794692aeed97caf68c5ef82923 Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Wed, 4 Mar 2020 19:17:42 -0500
Subject: [PATCH 4/7] tidy usage of block.has_content()

---
 src/compiler/compile/render_dom/Block.ts                     | 5 ++---
 src/compiler/compile/render_dom/index.ts                     | 2 +-
 .../compile/render_dom/wrappers/InlineComponent/index.ts     | 2 +-
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/compiler/compile/render_dom/Block.ts b/src/compiler/compile/render_dom/Block.ts
index f9273f7fc93c..2da77d3fbf52 100644
--- a/src/compiler/compile/render_dom/Block.ts
+++ b/src/compiler/compile/render_dom/Block.ts
@@ -411,9 +411,8 @@ export default class Block {
 		return body;
 	}
 
-	has_content(ignore_dev?: boolean) {
-		return (!ignore_dev && this.renderer.options.dev) ||
-			this.first ||
+	has_content() {
+		return this.first ||
 			this.event_listeners.length > 0 ||
 			this.chunks.intro.length > 0 ||
 			this.chunks.outro.length > 0  ||
diff --git a/src/compiler/compile/render_dom/index.ts b/src/compiler/compile/render_dom/index.ts
index 179115b5b248..466e8db4986d 100644
--- a/src/compiler/compile/render_dom/index.ts
+++ b/src/compiler/compile/render_dom/index.ts
@@ -264,7 +264,7 @@ export default function dom(
 		args.push(x`$$props`);
 	}
 
-	const has_create_fragment = block.has_content();
+	const has_create_fragment = component.compile_options.dev || block.has_content();
 	if (has_create_fragment) {
 		body.push(b`
 			function create_fragment(#ctx) {
diff --git a/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts b/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts
index 660e4831a2d5..8c8bd706962e 100644
--- a/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts
+++ b/src/compiler/compile/render_dom/wrappers/InlineComponent/index.ts
@@ -154,7 +154,7 @@ export default class InlineComponentWrapper extends Wrapper {
 
 		// removing empty slot
 		for (const slot of this.slots.keys()) {
-			if (!this.slots.get(slot).block.has_content(true)) {
+			if (!this.slots.get(slot).block.has_content()) {
 				this.slots.delete(slot);
 			}
 		}

From 43781ae44eb1e9b5e898daf670fd9e095927f75b Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Wed, 4 Mar 2020 19:21:02 -0500
Subject: [PATCH 5/7] update changelog

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

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b0672d790ea4..f39308e5ffa3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+* In `dev` mode, display a runtime warning when a component is passed an unexpected slot ([#1020](https://github.com/sveltejs/svelte/issues/1020), [#1447](https://github.com/sveltejs/svelte/issues/1447))
 * In `vars` array, correctly indicate whether `module` variables are `mutated` or `reassigned` ([#3215](https://github.com/sveltejs/svelte/issues/3215))
 * Fix spread props not updating in certain situations ([#3521](https://github.com/sveltejs/svelte/issues/3521), [#4480](https://github.com/sveltejs/svelte/issues/4480))
 * Use the fallback content for slots if they are passed only whitespace ([#4092](https://github.com/sveltejs/svelte/issues/4092))

From 16021129d80c1208e971e238e80386f047651c88 Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Wed, 4 Mar 2020 19:43:40 -0500
Subject: [PATCH 6/7] improve warning message

---
 src/compiler/compile/render_dom/index.ts | 2 +-
 src/runtime/internal/dev.ts              | 7 +++----
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/compiler/compile/render_dom/index.ts b/src/compiler/compile/render_dom/index.ts
index 466e8db4986d..fc3c94a2be19 100644
--- a/src/compiler/compile/render_dom/index.ts
+++ b/src/compiler/compile/render_dom/index.ts
@@ -413,7 +413,7 @@ export default function dom(
 				${unknown_props_check}
 
 				${component.slots.size || component.compile_options.dev ? b`let { $$slots = {}, $$scope } = $$props;` : null}
-				${component.compile_options.dev && b`@validate_slot($$slots, [${Array.from(component.slots.keys()).map(key => `"${key}"`).join(',')}]);`}
+				${component.compile_options.dev && b`@validate_slots('${component.tag}', $$slots, [${[...component.slots.keys()].map(key => `'${key}'`).join(',')}]);`}
 
 				${renderer.binding_groups.length > 0 && b`const $$binding_groups = [${renderer.binding_groups.map(_ => x`[]`)}];`}
 
diff --git a/src/runtime/internal/dev.ts b/src/runtime/internal/dev.ts
index 865f23ce1165..751f1f802bc0 100644
--- a/src/runtime/internal/dev.ts
+++ b/src/runtime/internal/dev.ts
@@ -89,11 +89,10 @@ export function validate_each_argument(arg) {
 	}
 }
 
-export function validate_slot(slot, keys) {
-	keys = new Set(keys);
+export function validate_slots(name, slot, keys) {
 	for (const slot_key of Object.keys(slot)) {
-		if (!keys.has(slot_key)) {
-			console.warn(`Received unexpected slot named "${slot_key}"`);
+		if (!~keys.indexOf(slot_key)) {
+			console.warn(`<${name}> received an unexpected slot "${slot_key}".`);
 		}
 	}
 }

From 0efe244e4069dbeaaa3a4bb3403b80e0ed02eec6 Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Wed, 4 Mar 2020 19:51:25 -0500
Subject: [PATCH 7/7] update tests

---
 test/js/samples/capture-inject-state/expected.js              | 4 ++--
 test/js/samples/debug-empty/expected.js                       | 4 ++--
 test/js/samples/debug-foo-bar-baz-things/expected.js          | 4 ++--
 test/js/samples/debug-foo/expected.js                         | 4 ++--
 test/js/samples/debug-hoisted/expected.js                     | 4 ++--
 test/js/samples/debug-no-dependencies/expected.js             | 4 ++--
 test/js/samples/dev-warning-missing-data-computed/expected.js | 4 ++--
 test/js/samples/loop-protect/expected.js                      | 4 ++--
 test/runtime/samples/component-slot-warning/_config.js        | 4 ++--
 9 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/test/js/samples/capture-inject-state/expected.js b/test/js/samples/capture-inject-state/expected.js
index 017d9868d543..cd719ac5d25f 100644
--- a/test/js/samples/capture-inject-state/expected.js
+++ b/test/js/samples/capture-inject-state/expected.js
@@ -14,7 +14,7 @@ import {
 	space,
 	subscribe,
 	text,
-	validate_slot,
+	validate_slots,
 	validate_store
 } from "svelte/internal";
 
@@ -116,7 +116,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 
 	$$self.$set = $$props => {
 		if ("prop" in $$props) $$subscribe_prop($$invalidate(0, prop = $$props.prop));
diff --git a/test/js/samples/debug-empty/expected.js b/test/js/samples/debug-empty/expected.js
index 6f16a655eede..dd142adb26b2 100644
--- a/test/js/samples/debug-empty/expected.js
+++ b/test/js/samples/debug-empty/expected.js
@@ -13,7 +13,7 @@ import {
 	set_data_dev,
 	space,
 	text,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const file = undefined;
@@ -77,7 +77,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 
 	$$self.$set = $$props => {
 		if ("name" in $$props) $$invalidate(0, name = $$props.name);
diff --git a/test/js/samples/debug-foo-bar-baz-things/expected.js b/test/js/samples/debug-foo-bar-baz-things/expected.js
index 4352e981f842..977702b99f5c 100644
--- a/test/js/samples/debug-foo-bar-baz-things/expected.js
+++ b/test/js/samples/debug-foo-bar-baz-things/expected.js
@@ -15,7 +15,7 @@ import {
 	space,
 	text,
 	validate_each_argument,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const file = undefined;
@@ -181,7 +181,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 
 	$$self.$set = $$props => {
 		if ("things" in $$props) $$invalidate(0, things = $$props.things);
diff --git a/test/js/samples/debug-foo/expected.js b/test/js/samples/debug-foo/expected.js
index 8767eb3acaba..fe62ff77bfb1 100644
--- a/test/js/samples/debug-foo/expected.js
+++ b/test/js/samples/debug-foo/expected.js
@@ -15,7 +15,7 @@ import {
 	space,
 	text,
 	validate_each_argument,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const file = undefined;
@@ -173,7 +173,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 
 	$$self.$set = $$props => {
 		if ("things" in $$props) $$invalidate(0, things = $$props.things);
diff --git a/test/js/samples/debug-hoisted/expected.js b/test/js/samples/debug-hoisted/expected.js
index a774f99b5de3..0e634297f08f 100644
--- a/test/js/samples/debug-hoisted/expected.js
+++ b/test/js/samples/debug-hoisted/expected.js
@@ -5,7 +5,7 @@ import {
 	init,
 	noop,
 	safe_not_equal,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const file = undefined;
@@ -58,7 +58,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 	$$self.$capture_state = () => ({ obj, kobzol });
 
 	$$self.$inject_state = $$props => {
diff --git a/test/js/samples/debug-no-dependencies/expected.js b/test/js/samples/debug-no-dependencies/expected.js
index 3f89b93bc11d..76068e8cf464 100644
--- a/test/js/samples/debug-no-dependencies/expected.js
+++ b/test/js/samples/debug-no-dependencies/expected.js
@@ -12,7 +12,7 @@ import {
 	space,
 	text,
 	validate_each_argument,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const file = undefined;
@@ -143,7 +143,7 @@ function instance($$self, $$props) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 	return [];
 }
 
diff --git a/test/js/samples/dev-warning-missing-data-computed/expected.js b/test/js/samples/dev-warning-missing-data-computed/expected.js
index 658260a080bf..0a50e2cd970a 100644
--- a/test/js/samples/dev-warning-missing-data-computed/expected.js
+++ b/test/js/samples/dev-warning-missing-data-computed/expected.js
@@ -13,7 +13,7 @@ import {
 	set_data_dev,
 	space,
 	text,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const file = undefined;
@@ -74,7 +74,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 
 	$$self.$set = $$props => {
 		if ("foo" in $$props) $$invalidate(0, foo = $$props.foo);
diff --git a/test/js/samples/loop-protect/expected.js b/test/js/samples/loop-protect/expected.js
index 3dfd75911e84..c52d9df437e5 100644
--- a/test/js/samples/loop-protect/expected.js
+++ b/test/js/samples/loop-protect/expected.js
@@ -12,7 +12,7 @@ import {
 	loop_guard,
 	noop,
 	safe_not_equal,
-	validate_slot
+	validate_slots
 } from "svelte/internal";
 
 const { console: console_1 } = globals;
@@ -112,7 +112,7 @@ function instance($$self, $$props, $$invalidate) {
 	});
 
 	let { $$slots = {}, $$scope } = $$props;
-	validate_slot($$slots, []);
+	validate_slots("Component", $$slots, []);
 
 	function div_binding($$value) {
 		binding_callbacks[$$value ? "unshift" : "push"](() => {
diff --git a/test/runtime/samples/component-slot-warning/_config.js b/test/runtime/samples/component-slot-warning/_config.js
index e652d8e4fd17..6ffe624782e0 100644
--- a/test/runtime/samples/component-slot-warning/_config.js
+++ b/test/runtime/samples/component-slot-warning/_config.js
@@ -3,7 +3,7 @@ export default {
 		dev: true
 	},
 	warnings: [
-		'Received unexpected slot named "default"',
-		'Received unexpected slot named "slot1"'
+		'<Nested> received an unexpected slot "default".',
+		'<Nested> received an unexpected slot "slot1".'
 	]
 };