From e33af522ab66fd5fe5dcff20549ff98fb034d165 Mon Sep 17 00:00:00 2001
From: Jeremiasz Major <jrh.mjr@gmail.com>
Date: Fri, 19 Apr 2024 16:11:41 +0200
Subject: [PATCH 1/2] treat special elements that never have content as void
 elements

---
 packages/svelte/src/compiler/errors.js        |   2 -
 .../compiler/phases/1-parse/state/element.js  |  13 +-
 .../compiler/phases/1-parse/utils/names.js    |   6 +-
 .../samples/void-special-children/_config.js  |   9 +
 .../main.svelte                               |   0
 .../samples/void-special-closing/_config.js   |   9 +
 .../samples/void-special-closing/main.svelte  |   1 +
 .../samples/window-children/_config.js        |   9 -
 .../void-special-elements/input.svelte        |   4 +
 .../samples/void-special-elements/output.json | 210 ++++++++++++++++++
 .../samples/deconflict-globals/main.svelte    |   4 +-
 .../samples/let-directive/input.svelte        |   2 +-
 12 files changed, 242 insertions(+), 27 deletions(-)
 create mode 100644 packages/svelte/tests/compiler-errors/samples/void-special-children/_config.js
 rename packages/svelte/tests/compiler-errors/samples/{window-children => void-special-children}/main.svelte (100%)
 create mode 100644 packages/svelte/tests/compiler-errors/samples/void-special-closing/_config.js
 create mode 100644 packages/svelte/tests/compiler-errors/samples/void-special-closing/main.svelte
 delete mode 100644 packages/svelte/tests/compiler-errors/samples/window-children/_config.js
 create mode 100644 packages/svelte/tests/parser-modern/samples/void-special-elements/input.svelte
 create mode 100644 packages/svelte/tests/parser-modern/samples/void-special-elements/output.json

diff --git a/packages/svelte/src/compiler/errors.js b/packages/svelte/src/compiler/errors.js
index ab0a17497e86..417599eefba9 100644
--- a/packages/svelte/src/compiler/errors.js
+++ b/packages/svelte/src/compiler/errors.js
@@ -229,8 +229,6 @@ const elements = {
 	'invalid-textarea-content': () =>
 		`A <textarea> can have either a value attribute or (equivalently) child content, but not both`,
 	'invalid-void-content': () => `Void elements cannot have children or closing tags`,
-	/** @param {string} name */
-	'invalid-element-content': (name) => `<${name}> cannot have children`,
 	'invalid-tag-name': () => 'Expected valid tag name',
 	/**
 	 * @param {string} node
diff --git a/packages/svelte/src/compiler/phases/1-parse/state/element.js b/packages/svelte/src/compiler/phases/1-parse/state/element.js
index 42c48a89ad74..932ad3f50b36 100644
--- a/packages/svelte/src/compiler/phases/1-parse/state/element.js
+++ b/packages/svelte/src/compiler/phases/1-parse/state/element.js
@@ -99,18 +99,7 @@ export default function tag(parser) {
 	const name = read_tag_name(parser);
 
 	if (root_only_meta_tags.has(name)) {
-		if (is_closing_tag) {
-			if (
-				(name === 'svelte:window' || name === 'svelte:body' || name === 'svelte:document') &&
-				/** @type {import('#compiler').ElementLike} */ (parent).fragment.nodes.length
-			) {
-				error(
-					/** @type {import('#compiler').ElementLike} */ (parent).fragment.nodes[0].start,
-					'invalid-element-content',
-					name
-				);
-			}
-		} else {
+		if (!is_closing_tag) {
 			if (name in parser.meta_tags) {
 				error(start, 'duplicate-svelte-element', name);
 			}
diff --git a/packages/svelte/src/compiler/phases/1-parse/utils/names.js b/packages/svelte/src/compiler/phases/1-parse/utils/names.js
index 26dd20e40be5..f175546ca532 100644
--- a/packages/svelte/src/compiler/phases/1-parse/utils/names.js
+++ b/packages/svelte/src/compiler/phases/1-parse/utils/names.js
@@ -65,7 +65,11 @@ const void_element_names = [
 	'param',
 	'source',
 	'track',
-	'wbr'
+	'wbr',
+	'svelte:options',
+	'svelte:window',
+	'svelte:document',
+	'svelte:body'
 ];
 
 /** @param {string} name */
diff --git a/packages/svelte/tests/compiler-errors/samples/void-special-children/_config.js b/packages/svelte/tests/compiler-errors/samples/void-special-children/_config.js
new file mode 100644
index 000000000000..704d8c602978
--- /dev/null
+++ b/packages/svelte/tests/compiler-errors/samples/void-special-children/_config.js
@@ -0,0 +1,9 @@
+import { test } from '../../test';
+
+export default test({
+	error: {
+		code: 'invalid-void-content',
+		message: 'Void elements cannot have children or closing tags',
+		position: [23, 23]
+	}
+});
diff --git a/packages/svelte/tests/compiler-errors/samples/window-children/main.svelte b/packages/svelte/tests/compiler-errors/samples/void-special-children/main.svelte
similarity index 100%
rename from packages/svelte/tests/compiler-errors/samples/window-children/main.svelte
rename to packages/svelte/tests/compiler-errors/samples/void-special-children/main.svelte
diff --git a/packages/svelte/tests/compiler-errors/samples/void-special-closing/_config.js b/packages/svelte/tests/compiler-errors/samples/void-special-closing/_config.js
new file mode 100644
index 000000000000..59d0d721ee73
--- /dev/null
+++ b/packages/svelte/tests/compiler-errors/samples/void-special-closing/_config.js
@@ -0,0 +1,9 @@
+import { test } from '../../test';
+
+export default test({
+	error: {
+		code: 'invalid-void-content',
+		message: 'Void elements cannot have children or closing tags',
+		position: [33, 33]
+	}
+});
diff --git a/packages/svelte/tests/compiler-errors/samples/void-special-closing/main.svelte b/packages/svelte/tests/compiler-errors/samples/void-special-closing/main.svelte
new file mode 100644
index 000000000000..cd9f581539f8
--- /dev/null
+++ b/packages/svelte/tests/compiler-errors/samples/void-special-closing/main.svelte
@@ -0,0 +1 @@
+<svelte:options immutable={true}></svelte:options>
diff --git a/packages/svelte/tests/compiler-errors/samples/window-children/_config.js b/packages/svelte/tests/compiler-errors/samples/window-children/_config.js
deleted file mode 100644
index 33b57bf5f6f7..000000000000
--- a/packages/svelte/tests/compiler-errors/samples/window-children/_config.js
+++ /dev/null
@@ -1,9 +0,0 @@
-import { test } from '../../test';
-
-export default test({
-	error: {
-		code: 'invalid-element-content',
-		message: '<svelte:window> cannot have children',
-		position: [15, 15]
-	}
-});
diff --git a/packages/svelte/tests/parser-modern/samples/void-special-elements/input.svelte b/packages/svelte/tests/parser-modern/samples/void-special-elements/input.svelte
new file mode 100644
index 000000000000..1c184301a367
--- /dev/null
+++ b/packages/svelte/tests/parser-modern/samples/void-special-elements/input.svelte
@@ -0,0 +1,4 @@
+<svelte:options immutable={false}>
+<svelte:window on:event={() => null}>
+<svelte:document on:event={() => null}>
+<svelte:body on:event={() => null}>
diff --git a/packages/svelte/tests/parser-modern/samples/void-special-elements/output.json b/packages/svelte/tests/parser-modern/samples/void-special-elements/output.json
new file mode 100644
index 000000000000..482d567d6f25
--- /dev/null
+++ b/packages/svelte/tests/parser-modern/samples/void-special-elements/output.json
@@ -0,0 +1,210 @@
+{
+	"css": null,
+	"js": [],
+	"start": 0,
+	"end": 148,
+	"type": "Root",
+	"fragment": {
+		"type": "Fragment",
+		"nodes": [
+			{
+				"type": "Text",
+				"start": 34,
+				"end": 35,
+				"raw": "\n",
+				"data": "\n"
+			},
+			{
+				"type": "SvelteWindow",
+				"start": 35,
+				"end": 72,
+				"name": "svelte:window",
+				"attributes": [
+					{
+						"start": 50,
+						"end": 71,
+						"type": "OnDirective",
+						"name": "event",
+						"modifiers": [],
+						"expression": {
+							"type": "ArrowFunctionExpression",
+							"start": 60,
+							"end": 70,
+							"loc": {
+								"start": {
+									"line": 2,
+									"column": 25
+								},
+								"end": {
+									"line": 2,
+									"column": 35
+								}
+							},
+							"id": null,
+							"expression": true,
+							"generator": false,
+							"async": false,
+							"params": [],
+							"body": {
+								"type": "Literal",
+								"start": 66,
+								"end": 70,
+								"loc": {
+									"start": {
+										"line": 2,
+										"column": 31
+									},
+									"end": {
+										"line": 2,
+										"column": 35
+									}
+								},
+								"value": null,
+								"raw": "null"
+							}
+						}
+					}
+				],
+				"fragment": {
+					"type": "Fragment",
+					"nodes": [],
+					"transparent": true
+				}
+			},
+			{
+				"type": "Text",
+				"start": 72,
+				"end": 73,
+				"raw": "\n",
+				"data": "\n"
+			},
+			{
+				"type": "SvelteDocument",
+				"start": 73,
+				"end": 112,
+				"name": "svelte:document",
+				"attributes": [
+					{
+						"start": 90,
+						"end": 111,
+						"type": "OnDirective",
+						"name": "event",
+						"modifiers": [],
+						"expression": {
+							"type": "ArrowFunctionExpression",
+							"start": 100,
+							"end": 110,
+							"loc": {
+								"start": {
+									"line": 3,
+									"column": 27
+								},
+								"end": {
+									"line": 3,
+									"column": 37
+								}
+							},
+							"id": null,
+							"expression": true,
+							"generator": false,
+							"async": false,
+							"params": [],
+							"body": {
+								"type": "Literal",
+								"start": 106,
+								"end": 110,
+								"loc": {
+									"start": {
+										"line": 3,
+										"column": 33
+									},
+									"end": {
+										"line": 3,
+										"column": 37
+									}
+								},
+								"value": null,
+								"raw": "null"
+							}
+						}
+					}
+				],
+				"fragment": {
+					"type": "Fragment",
+					"nodes": [],
+					"transparent": true
+				}
+			},
+			{
+				"type": "Text",
+				"start": 112,
+				"end": 113,
+				"raw": "\n",
+				"data": "\n"
+			},
+			{
+				"type": "SvelteBody",
+				"start": 113,
+				"end": 148,
+				"name": "svelte:body",
+				"attributes": [
+					{
+						"start": 126,
+						"end": 147,
+						"type": "OnDirective",
+						"name": "event",
+						"modifiers": [],
+						"expression": {
+							"type": "ArrowFunctionExpression",
+							"start": 136,
+							"end": 146,
+							"loc": {
+								"start": {
+									"line": 4,
+									"column": 23
+								},
+								"end": {
+									"line": 4,
+									"column": 33
+								}
+							},
+							"id": null,
+							"expression": true,
+							"generator": false,
+							"async": false,
+							"params": [],
+							"body": {
+								"type": "Literal",
+								"start": 142,
+								"end": 146,
+								"loc": {
+									"start": {
+										"line": 4,
+										"column": 29
+									},
+									"end": {
+										"line": 4,
+										"column": 33
+									}
+								},
+								"value": null,
+								"raw": "null"
+							}
+						}
+					}
+				],
+				"fragment": {
+					"type": "Fragment",
+					"nodes": [],
+					"transparent": true
+				}
+			}
+		],
+		"transparent": false
+	},
+	"options": {
+		"start": 0,
+		"end": 34,
+		"immutable": false
+	}
+}
diff --git a/packages/svelte/tests/runtime-legacy/samples/deconflict-globals/main.svelte b/packages/svelte/tests/runtime-legacy/samples/deconflict-globals/main.svelte
index d1928ea5335d..156457971ff3 100644
--- a/packages/svelte/tests/runtime-legacy/samples/deconflict-globals/main.svelte
+++ b/packages/svelte/tests/runtime-legacy/samples/deconflict-globals/main.svelte
@@ -12,8 +12,8 @@
 	<title>Cute test</title>
 </svelte:head>
 
-<svelte:window on:click></svelte:window>
-<svelte:body on:mouseenter></svelte:body>
+<svelte:window on:click>
+<svelte:body on:mouseenter>
 
 {#each everyone as someone (someone)}
 	<p>{someone}</p>
diff --git a/packages/svelte/tests/validator/samples/let-directive/input.svelte b/packages/svelte/tests/validator/samples/let-directive/input.svelte
index 90763028b767..ff545d10f530 100644
--- a/packages/svelte/tests/validator/samples/let-directive/input.svelte
+++ b/packages/svelte/tests/validator/samples/let-directive/input.svelte
@@ -3,4 +3,4 @@
 {/if}
 <Component let:x></Component>
 <div let:x></div><!-- strictly speaking this is invalid, but it was never checked in Svelte 3/4 either, and is now deprecated, so don't mind -->
-<svelte:window let:x></svelte:window>
\ No newline at end of file
+<svelte:window let:x>

From 54ab321b356990fe841bb30522258f4e6dba5bd8 Mon Sep 17 00:00:00 2001
From: Jeremiasz Major <jrh.mjr@gmail.com>
Date: Fri, 19 Apr 2024 17:02:35 +0200
Subject: [PATCH 2/2] add changeset

---
 .changeset/hot-cups-sort.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/hot-cups-sort.md

diff --git a/.changeset/hot-cups-sort.md b/.changeset/hot-cups-sort.md
new file mode 100644
index 000000000000..92151c56e66b
--- /dev/null
+++ b/.changeset/hot-cups-sort.md
@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+breaking: treat special elements that never have content as void elements