push wrong hydratable

packages/svelte/src/compiler/phases/3-transform/server/visitors/AwaitBlock.js

@@ -1,6 +1,7 @@
-/** @import { BlockStatement, Expression, Pattern } from 'estree' */
+/** @import { BlockStatement, Expression, Pattern, Statement } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { ComponentContext } from '../types.js' */
+import { is_hydratable } from '../../../../../internal/server/hydration.js';
 import * as b from '../../../../utils/builders.js';
 import { empty_comment } from './shared/utils.js';
 
@@ -9,8 +10,8 @@ import { empty_comment } from './shared/utils.js';
  * @param {ComponentContext} context
  */
 export function AwaitBlock(node, context) {
-	context.state.template.push(
-		empty_comment,
+	const hydratable = is_hydratable();
+	const templates = /** @type {Array<Expression | Statement>} */ ([
 		b.stmt(
 			b.call(
 				'$.await',
@@ -27,7 +28,13 @@ export function AwaitBlock(node, context) {
 					node.catch ? /** @type {BlockStatement} */ (context.visit(node.catch)) : b.block([])
 				)
 			)
-		),
-		empty_comment
-	);
+		)
+	]);
+
+	if (hydratable) {
+		templates.unshift(empty_comment);
+		templates.push(empty_comment);
+	}
+
+	context.state.template.push(...templates);
 }

packages/svelte/src/compiler/phases/3-transform/server/visitors/EachBlock.js

@@ -1,7 +1,7 @@
 /** @import { BlockStatement, Expression, Pattern, Statement } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { ComponentContext } from '../types.js' */
-import { BLOCK_OPEN_ELSE } from '../../../../../internal/server/hydration.js';
+import { BLOCK_OPEN_ELSE, is_hydratable } from '../../../../../internal/server/hydration.js';
 import * as b from '../../../../utils/builders.js';
 import { block_close, block_open } from './shared/utils.js';
 
@@ -10,6 +10,7 @@ import { block_close, block_open } from './shared/utils.js';
  * @param {ComponentContext} context
  */
 export function EachBlock(node, context) {
+	const hydratable = is_hydratable();
 	const state = context.state;
 
 	const each_node_meta = node.metadata;
@@ -40,23 +41,32 @@ export function EachBlock(node, context) {
 	);
 
 	if (node.fallback) {
-		const open = b.stmt(b.assignment('+=', b.id('$$payload.out'), block_open));
-
 		const fallback = /** @type {BlockStatement} */ (context.visit(node.fallback));
 
-		fallback.body.unshift(
-			b.stmt(b.assignment('+=', b.id('$$payload.out'), b.literal(BLOCK_OPEN_ELSE)))
-		);
-
-		state.template.push(
-			b.if(
-				b.binary('!==', b.member(array_id, 'length'), b.literal(0)),
-				b.block([open, for_loop]),
-				fallback
-			),
-			block_close
-		);
+		const block = /** @type {Statement[]} */ ([for_loop]);
+
+		if (hydratable) {
+			block.unshift(b.stmt(b.assignment('+=', b.id('$$payload.out'), block_open)));
+
+			fallback.body.unshift(
+				b.stmt(b.assignment('+=', b.id('$$payload.out'), b.literal(BLOCK_OPEN_ELSE)))
+			);
+		}
+
+		const templates = /** @type {Array<Expression | Statement>} */ ([
+			b.if(b.binary('!==', b.member(array_id, 'length'), b.literal(0)), b.block(block), fallback)
+		]);
+		if (hydratable) {
+			templates.push(block_close);
+		}
+
+		state.template.push(...templates);
 	} else {
-		state.template.push(block_open, for_loop, block_close);
+		const templates = /** @type {Array<Expression | Statement>} */ ([for_loop]);
+		if (hydratable) {
+			templates.unshift(block_open);
+			templates.push(block_close);
+		}
+		state.template.push(...templates);
 	}
 }

packages/svelte/src/compiler/phases/3-transform/server/visitors/Fragment.js

@@ -3,6 +3,7 @@
 import { clean_nodes, infer_namespace } from '../../utils.js';
 import * as b from '../../../../utils/builders.js';
 import { empty_comment, process_children, build_template } from './shared/utils.js';
+import { is_hydratable } from '../../../../../internal/server/hydration.js';
 
 /**
  * @param {AST.Fragment} node
@@ -35,7 +36,8 @@ export function Fragment(node, context) {
 		context.visit(node, state);
 	}
 
-	if (is_text_first) {
+	if (is_text_first && is_hydratable()) {
+		console.log({ hid: is_hydratable() });
 		// insert `<!---->` to prevent this from being glued to the previous fragment
 		state.template.push(empty_comment);
 	}

packages/svelte/src/compiler/phases/3-transform/server/visitors/IfBlock.js

@@ -1,7 +1,7 @@
 /** @import { BlockStatement, Expression } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { ComponentContext } from '../types.js' */
-import { BLOCK_OPEN_ELSE } from '../../../../../internal/server/hydration.js';
+import { BLOCK_OPEN_ELSE, is_hydratable } from '../../../../../internal/server/hydration.js';
 import * as b from '../../../../utils/builders.js';
 import { block_close, block_open } from './shared/utils.js';
 
@@ -10,6 +10,7 @@ import { block_close, block_open } from './shared/utils.js';
  * @param {ComponentContext} context
  */
 export function IfBlock(node, context) {
+	const hydratable = is_hydratable();
 	const test = /** @type {Expression} */ (context.visit(node.test));
 
 	const consequent = /** @type {BlockStatement} */ (context.visit(node.consequent));
@@ -18,11 +19,13 @@ export function IfBlock(node, context) {
 		? /** @type {BlockStatement} */ (context.visit(node.alternate))
 		: b.block([]);
 
-	consequent.body.unshift(b.stmt(b.assignment('+=', b.id('$$payload.out'), block_open)));
+	if (hydratable) {
+		consequent.body.unshift(b.stmt(b.assignment('+=', b.id('$$payload.out'), block_open)));
 
-	alternate.body.unshift(
-		b.stmt(b.assignment('+=', b.id('$$payload.out'), b.literal(BLOCK_OPEN_ELSE)))
-	);
+		alternate.body.unshift(
+			b.stmt(b.assignment('+=', b.id('$$payload.out'), b.literal(BLOCK_OPEN_ELSE)))
+		);
+	}
 
 	context.state.template.push(b.if(test, consequent, alternate), block_close);
 }

packages/svelte/src/compiler/phases/3-transform/server/visitors/KeyBlock.js

@@ -1,6 +1,7 @@
-/** @import { BlockStatement } from 'estree' */
+/** @import { BlockStatement, Expression, Statement } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { ComponentContext } from '../types.js' */
+import { is_hydratable } from '../../../../../internal/server/hydration.js';
 import { empty_comment } from './shared/utils.js';
 
 /**
@@ -8,9 +9,14 @@ import { empty_comment } from './shared/utils.js';
  * @param {ComponentContext} context
  */
 export function KeyBlock(node, context) {
-	context.state.template.push(
-		empty_comment,
-		/** @type {BlockStatement} */ (context.visit(node.fragment)),
-		empty_comment
-	);
+	const templates = /** @type {Array<Expression | Statement>} */ ([
+		/** @type {BlockStatement} */ (context.visit(node.fragment))
+	]);
+
+	if (is_hydratable()) {
+		templates.unshift(empty_comment);
+		templates.push(empty_comment);
+	}
+
+	context.state.template.push(...templates);
 }

packages/svelte/src/compiler/phases/3-transform/server/visitors/RenderTag.js

@@ -1,6 +1,7 @@
 /** @import { Expression } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { ComponentContext } from '../types.js' */
+import { is_hydratable } from '../../../../../internal/server/hydration.js';
 import { unwrap_optional } from '../../../../utils/ast.js';
 import * as b from '../../../../utils/builders.js';
 import { empty_comment } from './shared/utils.js';
@@ -29,7 +30,7 @@ export function RenderTag(node, context) {
 		)
 	);
 
-	if (!context.state.skip_hydration_boundaries) {
+	if (!context.state.skip_hydration_boundaries && is_hydratable()) {
 		context.state.template.push(empty_comment);
 	}
 }

packages/svelte/src/compiler/phases/3-transform/server/visitors/SlotElement.js

@@ -1,6 +1,7 @@
-/** @import { BlockStatement, Expression, Literal, Property } from 'estree' */
+/** @import { BlockStatement, Expression, Literal, Property, Statement } from 'estree' */
 /** @import { AST } from '#compiler' */
 /** @import { ComponentContext } from '../types.js' */
+import { is_hydratable } from '../../../../../internal/server/hydration.js';
 import * as b from '../../../../utils/builders.js';
 import { empty_comment, build_attribute_value } from './shared/utils.js';
 
@@ -50,5 +51,12 @@ export function SlotElement(node, context) {
 		fallback
 	);
 
-	context.state.template.push(empty_comment, b.stmt(slot), empty_comment);
+	const templates = /** @type {Array<Expression | Statement>} */ ([b.stmt(slot)]);
+
+	if (is_hydratable()) {
+		templates.unshift(empty_comment);
+		templates.push(empty_comment);
+	}
+
+	context.state.template.push(...templates);
 }

packages/svelte/src/compiler/phases/3-transform/server/visitors/shared/component.js

@@ -4,6 +4,7 @@
 import { empty_comment, build_attribute_value } from './utils.js';
 import * as b from '../../../../../utils/builders.js';
 import { is_element_node } from '../../../../nodes.js';
+import { is_hydratable } from '../../../../../../internal/server/hydration.js';
 
 /**
  * @param {AST.Component | AST.SvelteComponent | AST.SvelteSelf} node
@@ -268,13 +269,14 @@ export function build_inline_component(node, expression, context) {
 			)
 		);
 	} else {
-		if (dynamic) {
+		const hydratable = is_hydratable();
+		if (dynamic && hydratable) {
 			context.state.template.push(empty_comment);
 		}
 
 		context.state.template.push(statement);
 
-		if (!context.state.skip_hydration_boundaries) {
+		if (!context.state.skip_hydration_boundaries && hydratable) {
 			context.state.template.push(empty_comment);
 		}
 	}

packages/svelte/src/internal/server/blocks/html.js

@@ -1,11 +1,13 @@
 import { DEV } from 'esm-env';
 import { hash } from '../../../utils.js';
+import { EMPTY_COMMENT, is_hydratable } from '../hydration.js';
 
 /**
  * @param {string} value
  */
 export function html(value) {
+	const hydratable = is_hydratable();
 	var html = String(value ?? '');
-	var open = DEV ? `<!--${hash(html)}-->` : '<!---->';
-	return open + html + '<!---->';
+	var open = hydratable ? (DEV ? `<!--${hash(html)}-->` : EMPTY_COMMENT) : '';
+	return open + html + (hydratable ? EMPTY_COMMENT : '');
 }

packages/svelte/src/internal/server/hydration.js

@@ -4,3 +4,17 @@ export const BLOCK_OPEN = `<!--${HYDRATION_START}-->`;
 export const BLOCK_OPEN_ELSE = `<!--${HYDRATION_START_ELSE}-->`;
 export const BLOCK_CLOSE = `<!--${HYDRATION_END}-->`;
 export const EMPTY_COMMENT = `<!---->`;
+
+let hydratable = true;
+
+export function is_hydratable() {
+	return hydratable;
+}
+
+/**
+ *
+ * @param {boolean} new_hydratable
+ */
+export function set_hydratable(new_hydratable) {
+	hydratable = new_hydratable;
+}

packages/svelte/src/internal/server/index.js

@@ -14,7 +14,13 @@ import {
 import { escape_html } from '../../escaping.js';
 import { DEV } from 'esm-env';
 import { current_component, pop, push } from './context.js';
-import { EMPTY_COMMENT, BLOCK_CLOSE, BLOCK_OPEN } from './hydration.js';
+import {
+	EMPTY_COMMENT,
+	BLOCK_CLOSE,
+	BLOCK_OPEN,
+	set_hydratable,
+	is_hydratable
+} from './hydration.js';
 import { validate_store } from '../shared/validate.js';
 import { is_boolean_attribute, is_void } from '../../utils.js';
 import { reset_elements } from './dev.js';
@@ -61,7 +67,9 @@ export function assign_payload(p1, p2) {
  * @returns {void}
  */
 export function element(payload, tag, attributes_fn = noop, children_fn = noop) {
-	payload.out += '<!---->';
+	let hydratable = is_hydratable();
+
+	if (hydratable) payload.out += EMPTY_COMMENT;
 
 	if (tag) {
 		payload.out += `<${tag} `;
@@ -70,14 +78,14 @@ export function element(payload, tag, attributes_fn = noop, children_fn = noop)
 
 		if (!is_void(tag)) {
 			children_fn();
-			if (!RAW_TEXT_ELEMENTS.includes(tag)) {
+			if (!RAW_TEXT_ELEMENTS.includes(tag) && hydratable) {
 				payload.out += EMPTY_COMMENT;
 			}
 			payload.out += `</${tag}>`;
 		}
 	}
 
-	payload.out += '<!---->';
+	if (hydratable) payload.out += EMPTY_COMMENT;
 }
 
 /**
@@ -91,16 +99,20 @@ export let on_destroy = [];
  * Takes a component and returns an object with `body` and `head` properties on it, which you can use to populate the HTML when server-rendering your app.
  * @template {Record<string, any>} Props
  * @param {import('svelte').Component<Props> | ComponentType<SvelteComponent<Props>>} component
- * @param {{ props?: Omit<Props, '$$slots' | '$$events'>; context?: Map<any, any> }} [options]
+ * @param {{ props?: Omit<Props, '$$slots' | '$$events'>; context?: Map<any, any>, hydratable?: boolean }} [options]
  * @returns {RenderOutput}
  */
 export function render(component, options = {}) {
+	let hydratable = options?.hydratable ?? true;
+	console.log({ hydratable });
+	set_hydratable(hydratable);
+
 	/** @type {Payload} */
 	const payload = { out: '', css: new Set(), head: { title: '', out: '' } };
 
 	const prev_on_destroy = on_destroy;
 	on_destroy = [];
-	payload.out += BLOCK_OPEN;
+	if (hydratable) payload.out += BLOCK_OPEN;
 
 	let reset_reset_element;
 
@@ -125,7 +137,7 @@ export function render(component, options = {}) {
 		reset_reset_element();
 	}
 
-	payload.out += BLOCK_CLOSE;
+	if (hydratable) payload.out += BLOCK_CLOSE;
 	for (const cleanup of on_destroy) cleanup();
 	on_destroy = prev_on_destroy;
 
@@ -163,6 +175,8 @@ export function head(payload, fn) {
  * @returns {void}
  */
 export function css_props(payload, is_html, props, component, dynamic = false) {
+	let comment = is_hydratable() ? EMPTY_COMMENT : '';
+
 	const styles = style_object_to_string(props);
 
 	if (is_html) {
@@ -172,15 +186,15 @@ export function css_props(payload, is_html, props, component, dynamic = false) {
 	}
 
 	if (dynamic) {
-		payload.out += '<!---->';
+		payload.out += comment;
 	}
 
 	component();
 
 	if (is_html) {
-		payload.out += `<!----></svelte-css-wrapper>`;
+		payload.out += comment + `</svelte-css-wrapper>`;
 	} else {
-		payload.out += `<!----></g>`;
+		payload.out += comment + `</g>`;
 	}
 }
 

packages/svelte/tests/server-side-rendering/samples/hydratable-false/Component.svelte

@@ -0,0 +1 @@
+<slot />

packages/svelte/tests/server-side-rendering/samples/hydratable-false/_config.js

@@ -0,0 +1,5 @@
+import { test } from '../../test';
+
+export default test({
+	hydratable: false
+});

packages/svelte/tests/server-side-rendering/samples/hydratable-false/main.svelte

@@ -0,0 +1,28 @@
+<script lang="ts">
+	import Component from "./Component.svelte";
+</script>
+
+
+{#if true}
+	if
+{/if}
+
+{#each [] as i}
+	{i}
+{/each}
+
+{#await Promise.resolve() then x}
+	{x}
+{/await}
+
+{#key true}
+	cool
+{/key}
+
+{#snippet to_render()}
+	cool
+{/snippet}
+
+{@render to_render()}
+
+<Component />

packages/svelte/tests/server-side-rendering/test.ts

@@ -15,6 +15,7 @@ import type { CompileOptions } from '#compiler';
 interface SSRTest extends BaseTest {
 	compileOptions?: Partial<CompileOptions>;
 	props?: Record<string, any>;
+	hydratable?: boolean;
 	withoutNormalizeHtml?: boolean;
 	errors?: string[];
 }
@@ -33,7 +34,8 @@ const { test, run } = suite<SSRTest>(async (config, test_dir) => {
 
 	const Component = (await import(`${test_dir}/_output/server/main.svelte.js`)).default;
 	const expected_html = try_read_file(`${test_dir}/_expected.html`);
-	const rendered = render(Component, { props: config.props || {} });
+	console.log({ config });
+	const rendered = render(Component, { props: config.props || {}, hydratable: config.hydratable });
 	const { body, head } = rendered;
 
 	fs.writeFileSync(`${test_dir}/_output/rendered.html`, body);