All files / src/internal/client/dom/blocks if.js

98.85% Statements 86/87
95.83% Branches 23/24
100% Functions 1/1
98.78% Lines 81/82

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 72 73 74 75 76 77 78 79 80 81 82 832x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 814x 1755x 1517x 1517x 1517x 1517x 1755x 376x 376x 376x 2x 2x 2x 2x 2x 2x 376x 1517x 1755x 777x 44x 777x 733x 733x 776x 777x 58x 56x 58x 58x 1755x 740x   740x 194x 194x 740x 740x 336x 272x 336x 336x 740x 1516x 1755x 2x 2x 2x 814x 814x  
import { EFFECT_TRANSPARENT } from '../../constants.js';
import { hydrate_nodes, hydrating, set_hydrating } from '../hydration.js';
import { remove } from '../reconciler.js';
import { block, branch, pause_effect, resume_effect } from '../../reactivity/effects.js';
import { HYDRATION_END_ELSE } from '../../../../constants.js';
 
/**
 * @param {Comment} anchor
 * @param {() => boolean} get_condition
 * @param {(anchor: Node) => import('#client').Dom} consequent_fn
 * @param {null | ((anchor: Node) => import('#client').Dom)} [alternate_fn]
 * @param {boolean} [elseif] True if this is an `{:else if ...}` block rather than an `{#if ...}`, as that affects which transitions are considered 'local'
 * @returns {void}
 */
export function if_block(
	anchor,
	get_condition,
	consequent_fn,
	alternate_fn = null,
	elseif = false
) {
	/** @type {import('#client').Effect | null} */
	var consequent_effect = null;
 
	/** @type {import('#client').Effect | null} */
	var alternate_effect = null;
 
	/** @type {boolean | null} */
	var condition = null;
 
	var flags = elseif ? EFFECT_TRANSPARENT : 0;
 
	block(() => {
		if (condition === (condition = !!get_condition())) return;
 
		/** Whether or not there was a hydration mismatch. Needs to be a `let` or else it isn't treeshaken out */
		let mismatch = false;
 
		if (hydrating) {
			const is_else = anchor.data === HYDRATION_END_ELSE;
 
			if (condition === is_else) {
				// Hydration mismatch: remove everything inside the anchor and start fresh.
				// This could happen with `{#if browser}...{/if}`, for example
				remove(hydrate_nodes);
				set_hydrating(false);
				mismatch = true;
			}
		}
 
		if (condition) {
			if (consequent_effect) {
				resume_effect(consequent_effect);
			} else {
				consequent_effect = branch(() => consequent_fn(anchor));
			}
 
			if (alternate_effect) {
				pause_effect(alternate_effect, () => {
					alternate_effect = null;
				});
			}
		} else {
			if (alternate_effect) {
				resume_effect(alternate_effect);
			} else if (alternate_fn) {
				alternate_effect = branch(() => alternate_fn(anchor));
			}
 
			if (consequent_effect) {
				pause_effect(consequent_effect, () => {
					consequent_effect = null;
				});
			}
		}
 
		if (mismatch) {
			// continue in hydration mode
			set_hydrating(true);
		}
	}, flags);
}