move element code (#10778)

* move element code

* eslint nonsense

---------

Co-authored-by: Rich Harris <rich.harris@vercel.com>

Author: Rich-Harris

packages/svelte/src/internal/client/dom/elements/attributes.js

@@ -0,0 +1,363 @@
+import { DEV } from 'esm-env';
+import { hydrating } from '../../hydration.js';
+import { render_effect } from '../../reactivity/effects.js';
+import { get_descriptors, object_assign } from '../../utils.js';
+import { map_get, map_set } from '../../operations.js';
+import { AttributeAliases, DelegatedEvents, namespace_svg } from '../../../../constants.js';
+import { delegate } from './events.js';
+import { autofocus } from './misc.js';
+
+/**
+ * The value/checked attribute in the template actually corresponds to the defaultValue property, so we need
+ * to remove it upon hydration to avoid a bug when someone resets the form value.
+ * @param {HTMLInputElement | HTMLSelectElement} dom
+ * @returns {void}
+ */
+export function remove_input_attr_defaults(dom) {
+	if (hydrating) {
+		attr(dom, 'value', null);
+		attr(dom, 'checked', null);
+	}
+}
+
+/**
+ * @param {Element} dom
+ * @param {string} attribute
+ * @param {() => string} value
+ */
+export function attr_effect(dom, attribute, value) {
+	render_effect(() => {
+		attr(dom, attribute, value());
+	});
+}
+
+/**
+ * @param {Element} dom
+ * @param {string} attribute
+ * @param {string | null} value
+ */
+export function attr(dom, attribute, value) {
+	value = value == null ? null : value + '';
+
+	if (DEV) {
+		check_src_in_dev_hydration(dom, attribute, value);
+	}
+
+	if (
+		!hydrating ||
+		(dom.getAttribute(attribute) !== value &&
+			// If we reset those, they would result in another network request, which we want to avoid.
+			// We assume they are the same between client and server as checking if they are equal is expensive
+			// (we can't just compare the strings as they can be different between client and server but result in the
+			// same url, so we would need to create hidden anchor elements to compare them)
+			attribute !== 'src' &&
+			attribute !== 'href' &&
+			attribute !== 'srcset')
+	) {
+		if (value === null) {
+			dom.removeAttribute(attribute);
+		} else {
+			dom.setAttribute(attribute, value);
+		}
+	}
+}
+
+/**
+ * @param {Element} dom
+ * @param {string} attribute
+ * @param {() => string} value
+ */
+export function xlink_attr_effect(dom, attribute, value) {
+	render_effect(() => {
+		xlink_attr(dom, attribute, value());
+	});
+}
+
+/**
+ * @param {Element} dom
+ * @param {string} attribute
+ * @param {string} value
+ */
+export function xlink_attr(dom, attribute, value) {
+	dom.setAttributeNS('http://www.w3.org/1999/xlink', attribute, value);
+}
+
+/**
+ * @param {any} node
+ * @param {string} prop
+ * @param {() => any} value
+ */
+export function set_custom_element_data_effect(node, prop, value) {
+	render_effect(() => {
+		set_custom_element_data(node, prop, value());
+	});
+}
+
+/**
+ * @param {any} node
+ * @param {string} prop
+ * @param {any} value
+ */
+export function set_custom_element_data(node, prop, value) {
+	if (prop in node) {
+		node[prop] = typeof node[prop] === 'boolean' && value === '' ? true : value;
+	} else {
+		attr(node, prop, value);
+	}
+}
+
+/**
+ * Like `spread_attributes` but self-contained
+ * @param {Element & ElementCSSInlineStyle} dom
+ * @param {() => Record<string, unknown>[]} attrs
+ * @param {boolean} lowercase_attributes
+ * @param {string} css_hash
+ */
+export function spread_attributes_effect(dom, attrs, lowercase_attributes, css_hash) {
+	/** @type {Record<string, any> | undefined} */
+	var current;
+
+	render_effect(() => {
+		current = spread_attributes(dom, current, attrs(), lowercase_attributes, css_hash);
+	});
+}
+
+/**
+ * Spreads attributes onto a DOM element, taking into account the currently set attributes
+ * @param {Element & ElementCSSInlineStyle} dom
+ * @param {Record<string, unknown> | undefined} prev
+ * @param {Record<string, unknown>[]} attrs
+ * @param {boolean} lowercase_attributes
+ * @param {string} css_hash
+ * @returns {Record<string, unknown>}
+ */
+export function spread_attributes(dom, prev, attrs, lowercase_attributes, css_hash) {
+	var next = object_assign({}, ...attrs);
+	var has_hash = css_hash.length !== 0;
+
+	for (var key in prev) {
+		if (!(key in next)) {
+			next[key] = null;
+		}
+	}
+
+	if (has_hash && !next.class) {
+		next.class = '';
+	}
+
+	var setters = map_get(setters_cache, dom.nodeName);
+	if (!setters) map_set(setters_cache, dom.nodeName, (setters = get_setters(dom)));
+
+	for (key in next) {
+		var value = next[key];
+		if (value === prev?.[key]) continue;
+
+		var prefix = key[0] + key[1]; // this is faster than key.slice(0, 2)
+		if (prefix === '$$') continue;
+
+		if (prefix === 'on') {
+			/** @type {{ capture?: true }} */
+			var opts = {};
+			var event_name = key.slice(2);
+			var delegated = DelegatedEvents.includes(event_name);
+
+			if (
+				event_name.endsWith('capture') &&
+				event_name !== 'ongotpointercapture' &&
+				event_name !== 'onlostpointercapture'
+			) {
+				event_name = event_name.slice(0, -7);
+				opts.capture = true;
+			}
+
+			if (!delegated && prev?.[key]) {
+				dom.removeEventListener(event_name, /** @type {any} */ (prev[key]), opts);
+			}
+
+			if (value != null) {
+				if (!delegated) {
+					dom.addEventListener(event_name, value, opts);
+				} else {
+					// @ts-ignore
+					dom[`__${event_name}`] = value;
+					delegate([event_name]);
+				}
+			}
+		} else if (value == null) {
+			dom.removeAttribute(key);
+		} else if (key === 'style') {
+			dom.style.cssText = value + '';
+		} else if (key === 'autofocus') {
+			autofocus(/** @type {HTMLElement} */ (dom), Boolean(value));
+		} else if (key === '__value' || key === 'value') {
+			// @ts-ignore
+			dom.value = dom[key] = dom.__value = value;
+		} else {
+			var name = key;
+			if (lowercase_attributes) {
+				name = name.toLowerCase();
+				name = AttributeAliases[name] || name;
+			}
+
+			if (setters.includes(name)) {
+				if (DEV) {
+					check_src_in_dev_hydration(dom, name, value);
+				}
+
+				if (
+					!hydrating ||
+					//  @ts-ignore see attr method for an explanation of src/srcset
+					(dom[name] !== value && name !== 'src' && name !== 'href' && name !== 'srcset')
+				) {
+					// @ts-ignore
+					dom[name] = value;
+				}
+			} else if (typeof value !== 'function') {
+				if (has_hash && name === 'class') {
+					if (value) value += ' ';
+					value += css_hash;
+				}
+
+				attr(dom, name, value);
+			}
+		}
+	}
+
+	return next;
+}
+
+/**
+ * @param {Element} node
+ * @param {() => Record<string, unknown>[]} attrs
+ * @param {string} css_hash
+ */
+export function spread_dynamic_element_attributes_effect(node, attrs, css_hash) {
+	/** @type {Record<string, any> | undefined} */
+	var current;
+
+	render_effect(() => {
+		current = spread_dynamic_element_attributes(node, current, attrs(), css_hash);
+	});
+}
+
+/**
+ * @param {Element} node
+ * @param {Record<string, unknown> | undefined} prev
+ * @param {Record<string, unknown>[]} attrs
+ * @param {string} css_hash
+ */
+export function spread_dynamic_element_attributes(node, prev, attrs, css_hash) {
+	if (node.tagName.includes('-')) {
+		var next = object_assign({}, ...attrs);
+
+		for (var key in prev) {
+			if (!(key in next)) {
+				next[key] = null;
+			}
+		}
+
+		for (key in next) {
+			set_custom_element_data(node, key, next[key]);
+		}
+
+		return next;
+	} else {
+		return spread_attributes(
+			/** @type {Element & ElementCSSInlineStyle} */ (node),
+			prev,
+			attrs,
+			node.namespaceURI !== namespace_svg,
+			css_hash
+		);
+	}
+}
+
+/**
+ * List of attributes that should always be set through the attr method,
+ * because updating them through the property setter doesn't work reliably.
+ * In the example of `width`/`height`, the problem is that the setter only
+ * accepts numeric values, but the attribute can also be set to a string like `50%`.
+ * If this list becomes too big, rethink this approach.
+ */
+var always_set_through_set_attribute = ['width', 'height'];
+
+/** @type {Map<string, string[]>} */
+var setters_cache = new Map();
+
+/** @param {Element} element */
+function get_setters(element) {
+	/** @type {string[]} */
+	var setters = [];
+
+	// @ts-expect-error
+	var descriptors = get_descriptors(element.__proto__);
+
+	for (var key in descriptors) {
+		if (descriptors[key].set && !always_set_through_set_attribute.includes(key)) {
+			setters.push(key);
+		}
+	}
+
+	return setters;
+}
+
+/**
+ * @param {any} dom
+ * @param {string} attribute
+ * @param {string | null} value
+ */
+function check_src_in_dev_hydration(dom, attribute, value) {
+	if (!hydrating) return;
+	if (attribute !== 'src' && attribute !== 'href' && attribute !== 'srcset') return;
+
+	if (attribute === 'srcset' && srcset_url_equal(dom, value)) return;
+	if (src_url_equal(dom.getAttribute(attribute) ?? '', value ?? '')) return;
+
+	// eslint-disable-next-line no-console
+	console.error(
+		`Detected a ${attribute} attribute value change during hydration. This will not be repaired during hydration, ` +
+			`the ${attribute} value that came from the server will be used. Related element:`,
+		dom,
+		' Differing value:',
+		value
+	);
+}
+
+/**
+ * @param {string} element_src
+ * @param {string} url
+ * @returns {boolean}
+ */
+function src_url_equal(element_src, url) {
+	if (element_src === url) return true;
+	return new URL(element_src, document.baseURI).href === new URL(url, document.baseURI).href;
+}
+
+/** @param {string} srcset */
+function split_srcset(srcset) {
+	return srcset.split(',').map((src) => src.trim().split(' ').filter(Boolean));
+}
+
+/**
+ * @param {HTMLSourceElement | HTMLImageElement} element
+ * @param {string | undefined | null} srcset
+ * @returns {boolean}
+ */
+export function srcset_url_equal(element, srcset) {
+	var element_urls = split_srcset(element.srcset);
+	var urls = split_srcset(srcset ?? '');
+
+	return (
+		urls.length === element_urls.length &&
+		urls.every(
+			([url, width], i) =>
+				width === element_urls[i][1] &&
+				// We need to test both ways because Vite will create an a full URL with
+				// `new URL(asset, import.meta.url).href` for the client when `base: './'`, and the
+				// relative URLs inside srcset are not automatically resolved to absolute URLs by
+				// browsers (in contrast to img.src). This means both SSR and DOM code could
+				// contain relative or absolute URLs.
+				(src_url_equal(element_urls[i][0], url) || src_url_equal(url, element_urls[i][0]))
+		)
+	);
+}