From 2fc5bab2fbf3f5f1c83aedac86fa9dde67dd6894 Mon Sep 17 00:00:00 2001
From: Karl Erik Hofseth <karl.e.hofseth@infomedia.dk>
Date: Fri, 19 Aug 2022 16:25:11 +0200
Subject: [PATCH 1/8] Make inserted style tag non-empty

---
 src/runtime/internal/dom.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/runtime/internal/dom.ts b/src/runtime/internal/dom.ts
index d359513eb417..1a5c8102b3f5 100644
--- a/src/runtime/internal/dom.ts
+++ b/src/runtime/internal/dom.ts
@@ -156,6 +156,7 @@ export function get_root_for_style(node: Node): ShadowRoot | Document {
 
 export function append_empty_stylesheet(node: Node) {
 	const style_element = element('style') as HTMLStyleElement;
+	style_element.textContent = '/* empty */';
 	append_stylesheet(get_root_for_style(node), style_element);
 	return style_element.sheet as CSSStyleSheet;
 }

From 8e33adf3334fd3c1d75bb5f41fab09104dace717 Mon Sep 17 00:00:00 2001
From: Karl Erik Hofseth <karl.e.hofseth@infomedia.dk>
Date: Fri, 19 Aug 2022 16:39:48 +0200
Subject: [PATCH 2/8] Don't replace existing style content, only empty

---
 src/runtime/internal/dom.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/runtime/internal/dom.ts b/src/runtime/internal/dom.ts
index 1a5c8102b3f5..7856ccc384e4 100644
--- a/src/runtime/internal/dom.ts
+++ b/src/runtime/internal/dom.ts
@@ -156,7 +156,7 @@ export function get_root_for_style(node: Node): ShadowRoot | Document {
 
 export function append_empty_stylesheet(node: Node) {
 	const style_element = element('style') as HTMLStyleElement;
-	style_element.textContent = '/* empty */';
+	style_element.textContent = style_element.textContent || '/* empty */';
 	append_stylesheet(get_root_for_style(node), style_element);
 	return style_element.sheet as CSSStyleSheet;
 }

From da5ddd40b42f5d5c6148f6430af211f09a4a5f0d Mon Sep 17 00:00:00 2001
From: Karl Erik Hofseth <karl.e.hofseth@infomedia.dk>
Date: Sat, 20 Aug 2022 10:12:39 +0200
Subject: [PATCH 3/8] Add comment explaining why this madness

---
 src/runtime/internal/dom.ts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/runtime/internal/dom.ts b/src/runtime/internal/dom.ts
index 7856ccc384e4..2c0b141fb59a 100644
--- a/src/runtime/internal/dom.ts
+++ b/src/runtime/internal/dom.ts
@@ -156,6 +156,11 @@ export function get_root_for_style(node: Node): ShadowRoot | Document {
 
 export function append_empty_stylesheet(node: Node) {
 	const style_element = element('style') as HTMLStyleElement;
+	// For transitions to work without 'style-src: unsafe-inline' Content Security Policy,
+	// these empty tags need to be allowed with a hash as a workaround until we move to the Web Animations API.
+	// Using the hash for the empty string (for an empty tag) works in all browsers except Safari.
+	// So as a workaround for the workaround, when we append empty style tags we set their content to /* empty */.
+	// The hash 'sha256-9OlNO0DNEeaVzHL4RZwCLsBHA8WBQ8toBp/4F5XV2nc=' will then work even in Safari.
 	style_element.textContent = style_element.textContent || '/* empty */';
 	append_stylesheet(get_root_for_style(node), style_element);
 	return style_element.sheet as CSSStyleSheet;

From e106eb55b30bd89898ad374dd2ee99f6d65609cf Mon Sep 17 00:00:00 2001
From: Simon H <5968653+dummdidumm@users.noreply.github.com>
Date: Thu, 4 May 2023 16:04:33 +0200
Subject: [PATCH 4/8] Update src/runtime/internal/dom.ts

---
 src/runtime/internal/dom.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/runtime/internal/dom.ts b/src/runtime/internal/dom.ts
index 2c0b141fb59a..8778638c8b4b 100644
--- a/src/runtime/internal/dom.ts
+++ b/src/runtime/internal/dom.ts
@@ -161,7 +161,7 @@ export function append_empty_stylesheet(node: Node) {
 	// Using the hash for the empty string (for an empty tag) works in all browsers except Safari.
 	// So as a workaround for the workaround, when we append empty style tags we set their content to /* empty */.
 	// The hash 'sha256-9OlNO0DNEeaVzHL4RZwCLsBHA8WBQ8toBp/4F5XV2nc=' will then work even in Safari.
-	style_element.textContent = style_element.textContent || '/* empty */';
+	style_element.textContent = '/* empty */';
 	append_stylesheet(get_root_for_style(node), style_element);
 	return style_element.sheet as CSSStyleSheet;
 }

From 1231d9a5f1a98d0d496f818914f1b8395dbb5ddf Mon Sep 17 00:00:00 2001
From: Simon H <5968653+dummdidumm@users.noreply.github.com>
Date: Thu, 4 May 2023 16:38:10 +0200
Subject: [PATCH 5/8] force merge

---
 CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0d0ee54c0d2a..db61c31273a0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 # Svelte changelog
 
+hi
+
 ## Unreleased
 
 * Fix hydration issue with using `{@html}` and components in `svelte:head` ([#4533](https://github.com/sveltejs/svelte/issues/4533), [#6463](https://github.com/sveltejs/svelte/issues/6463), [#7444](https://github.com/sveltejs/svelte/issues/7444))

From b65d94d388ea8d31f2e1f03c7565a89f6b2a50d2 Mon Sep 17 00:00:00 2001
From: Simon H <5968653+dummdidumm@users.noreply.github.com>
Date: Thu, 4 May 2023 16:45:11 +0200
Subject: [PATCH 6/8] tests

---
 .../samples/style_manager-cleanup/_config.js                  | 4 ++--
 .../input.svelte                                              | 2 +-
 .../input.svelte                                              | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/runtime-puppeteer/samples/style_manager-cleanup/_config.js b/test/runtime-puppeteer/samples/style_manager-cleanup/_config.js
index b3a5a97e4596..47d7dee83f51 100644
--- a/test/runtime-puppeteer/samples/style_manager-cleanup/_config.js
+++ b/test/runtime-puppeteer/samples/style_manager-cleanup/_config.js
@@ -5,12 +5,12 @@ export default {
 	test: async ({ component, assert, window, waitUntil }) => {
 		assert.htmlEqual(window.document.head.innerHTML, '');
 		component.visible = true;
-		assert.htmlEqual(window.document.head.innerHTML, '<style></style>');
+		assert.htmlEqual(window.document.head.innerHTML, '<style>/* empty */</style>');
 		await waitUntil(() => window.document.head.innerHTML === '');
 		assert.htmlEqual(window.document.head.innerHTML, '');
 
 		component.visible = false;
-		assert.htmlEqual(window.document.head.innerHTML, '<style></style>');
+		assert.htmlEqual(window.document.head.innerHTML, '<style>/* empty */</style>');
 		await waitUntil(() => window.document.head.innerHTML === '');
 		assert.htmlEqual(window.document.head.innerHTML, '');
 	}
diff --git a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
index ffaeb2c09708..325841373f99 100644
--- a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
+++ b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
@@ -1,4 +1,4 @@
-<svelte:options tag="my-element" />
+<svelte:options customElement="my-element" />
 
 <h1>Heading 1</h1>
 <span>Span 1</span>
diff --git a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
index 1d98415321d7..faf34125b141 100644
--- a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
+++ b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
@@ -1,4 +1,4 @@
-<svelte:options tag="custom-element" />
+<svelte:options customElement="custom-element" />
 
 <h1>test</h1>
 <slot>

From 8e7eeada2a21ffe2eb59df2eb35dc88757435bc8 Mon Sep 17 00:00:00 2001
From: Simon H <5968653+dummdidumm@users.noreply.github.com>
Date: Thu, 4 May 2023 16:58:03 +0200
Subject: [PATCH 7/8] drive by fixes

---
 src/compiler/compile/css/Selector.ts          | 36 ++++++++-----------
 .../input.svelte                              |  8 ++---
 .../warnings.json                             |  2 +-
 .../input.svelte                              |  8 ++---
 .../warnings.json                             |  2 +-
 5 files changed, 25 insertions(+), 31 deletions(-)

diff --git a/src/compiler/compile/css/Selector.ts b/src/compiler/compile/css/Selector.ts
index 705e341601e1..7c1652bb551e 100644
--- a/src/compiler/compile/css/Selector.ts
+++ b/src/compiler/compile/css/Selector.ts
@@ -471,28 +471,22 @@ function get_element_parent(node: Element): Element | null {
 }
 
 /**
-	* Finds the given node's previous sibling in the DOM
-	*	
-	* Unless the component is a custom element (web component), which in this
-	* case, the <slot> element is actually real, the Svelte <slot> is just a 
-	* placeholder and is not actually real. Any children nodes in <slot>
-	* are 'flattened' and considered as the same level as the <slot>'s siblings
-	*
-	* e.g.
-	* <h1>Heading 1</h1>
-	* <slot>
-	*   <h2>Heading 2</h2>
-	* </slot>
-	*
-	* is considered to look like:
-	* <h1>Heading 1</h1>
-	* <h2>Heading 2</h2>
-	*/
+ * Finds the given node's previous sibling in the DOM
+ *
+ * The Svelte <slot> is just a placeholder and is not actually real. Any children nodes
+ * in <slot> are 'flattened' and considered as the same level as the <slot>'s siblings
+ *
+ * e.g.
+ * <h1>Heading 1</h1>
+ * <slot>
+ *   <h2>Heading 2</h2>
+ * </slot>
+ *
+ * is considered to look like:
+ * <h1>Heading 1</h1>
+ * <h2>Heading 2</h2>
+ */
 function find_previous_sibling(node: INode): INode {
-	if (node.component.compile_options.customElement) {
-		return node.prev;
-	}
-
 	let current_node: INode = node;
 	do { 
 		if (current_node.type === 'Slot') {
diff --git a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
index 325841373f99..455d1da1703d 100644
--- a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
+++ b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
@@ -8,13 +8,13 @@
 </slot>
 
 <style>
-	/* This will not get picked up */
-	h1 ~ p {
+	/* This will not be picked up */
+	h1 ~ slot > p {
 		color: red;
 	}
 
-	/* This will be picked up */
-	h1 ~ slot > p {
+	/* This will get picked up */
+	h1 ~ p {
 		color: red;
 	}
 </style>
diff --git a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
index 0336660cafc7..936109f53811 100644
--- a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
+++ b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
@@ -1,7 +1,7 @@
 [
   {
     "code": "css-unused-selector",
-    "message": "Unused CSS selector \"h1 ~ p\"",
+    "message": "Unused CSS selector \"h1 ~ slot > p\"",
     "start": {
       "column": 1,
       "line": 12
diff --git a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
index faf34125b141..0ec25f7ac4bd 100644
--- a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
+++ b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/input.svelte
@@ -7,12 +7,12 @@
 
 <style>
 	/* This will not be picked up */
-  h1 + span {
-    color: red;
-  }
+	h1 + slot > span {
+		color: red;
+	}
 
 	/* This will be picked up */
-	h1 + slot > span {
+	h1 + span {
 		color: red;
 	}
 </style>
diff --git a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
index 3ef66ebf60dc..9db06f83091b 100644
--- a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
+++ b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
@@ -5,7 +5,7 @@
       "column": 11,
       "line": 10
     },
-    "message": "Unused CSS selector \"h1 + span\"",
+    "message": "Unused CSS selector \"h1 + slot > span\"",
     "start": {
       "column": 2,
       "line": 10

From 14c680e1b7630b5738f8321c3dacbbb6e52eebb0 Mon Sep 17 00:00:00 2001
From: Simon H <5968653+dummdidumm@users.noreply.github.com>
Date: Thu, 4 May 2023 17:05:23 +0200
Subject: [PATCH 8/8] fix

---
 .../warnings.json                                             | 2 +-
 .../warnings.json                                             | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
index 936109f53811..c1db03aa548b 100644
--- a/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
+++ b/test/validator/samples/general-siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
@@ -7,7 +7,7 @@
       "line": 12
     },
     "end": {
-      "column": 7,
+      "column": 14,
       "line": 12
     }
   }
diff --git a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
index 9db06f83091b..c027e667609a 100644
--- a/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
+++ b/test/validator/samples/siblings-combinator-in-custom-element-selects-slot-fallback/warnings.json
@@ -2,12 +2,12 @@
   {
     "code": "css-unused-selector",
     "end": {
-      "column": 11,
+      "column": 17,
       "line": 10
     },
     "message": "Unused CSS selector \"h1 + slot > span\"",
     "start": {
-      "column": 2,
+      "column": 1,
       "line": 10
     }
   }