All files / src/internal/client/dom hydration.js

100% Statements 73/73
100% Branches 16/16
100% Functions 3/3
100% Lines 71/71

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 722x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 4404x 4404x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1465x 1465x 2x 2x 2x 2x 2x 2x 2x 2x 2x 12696x 6069x 6069x 6627x 6627x 6627x 6627x 12696x 5x 5x 6622x 6622x 6622x 6622x 6622x 12696x 39963x 26765x 26765x 26765x 10072x 26765x 16692x 6620x 6620x 6620x 10072x 10072x 10072x 26765x 33343x 33343x 33343x 2x 2x 2x  
import { HYDRATION_END, HYDRATION_START } from '../../../constants.js';
import * as e from '../errors.js';
 
/**
 * Use this variable to guard everything related to hydration code so it can be treeshaken out
 * if the user doesn't use the `hydrate` method and these code paths are therefore not needed.
 */
export let hydrating = false;
 
/** @param {boolean} value */
export function set_hydrating(value) {
	hydrating = value;
}
 
/**
 * Array of nodes to traverse for hydration. This will be null if we're not hydrating, but for
 * the sake of simplicity we're not going to use `null` checks everywhere and instead rely on
 * the `hydrating` flag to tell whether or not we're in hydration mode at which point this is set.
 * @type {import('#client').TemplateNode[]}
 */
export let hydrate_nodes = /** @type {any} */ (null);
 
/** @param {import('#client').TemplateNode[]} nodes */
export function set_hydrate_nodes(nodes) {
	hydrate_nodes = nodes;
}
 
/**
 * This function is only called when `hydrating` is true. If passed a `<!--[-->` opening
 * hydration marker, it finds the corresponding closing marker and sets `hydrate_nodes`
 * to everything between the markers, before returning the closing marker.
 * @param {Node} node
 * @returns {Node}
 */
export function hydrate_anchor(node) {
	if (node.nodeType !== 8) {
		return node;
	}
 
	var current = /** @type {Node | null} */ (node);
 
	// TODO this could have false positives, if a user comment consisted of `[`. need to tighten that up
	if (/** @type {Comment} */ (current)?.data !== HYDRATION_START) {
		return node;
	}
 
	/** @type {Node[]} */
	var nodes = [];
	var depth = 0;
 
	while ((current = /** @type {Node} */ (current).nextSibling) !== null) {
		if (current.nodeType === 8) {
			var data = /** @type {Comment} */ (current).data;
 
			if (data === HYDRATION_START) {
				depth += 1;
			} else if (data[0] === HYDRATION_END) {
				if (depth === 0) {
					hydrate_nodes = /** @type {import('#client').TemplateNode[]} */ (nodes);
					return current;
				}
 
				depth -= 1;
			}
		}
 
		nodes.push(current);
	}
 
	e.hydration_missing_marker_close();
}