All files / src/compiler/phases/3-transform/server/visitors AssignmentExpression.js

97.18% Statements 69/71
92.85% Branches 13/14
100% Functions 3/3
97.05% Lines 66/68

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 692x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1118x 1118x 2x 2x 2x 2x 2x 2x 2x 2x 2x 1170x 1170x 1170x 1170x 343x 343x 343x 1170x 1170x 1120x 1120x 50x 50x 50x 1139x     50x 1139x 40x 40x 40x 40x 40x 40x 10x 10x 10x 10x 10x 10x 10x 10x 10x 10x 10x 10x 10x 2x 2x 2x 2x 1114x 1114x 1114x  
/** @import { AssignmentExpression, AssignmentOperator, Expression, Pattern } from 'estree' */
/** @import { SvelteNode } from '#compiler' */
/** @import { Context, ServerTransformState } from '../types.js' */
import * as b from '../../../../utils/builders.js';
import { build_assignment_value } from '../../../../utils/ast.js';
import { visit_assignment_expression } from '../../shared/assignments.js';
 
/**
 * @param {AssignmentExpression} node
 * @param {Context} context
 */
export function AssignmentExpression(node, context) {
	return visit_assignment_expression(node, context, build_assignment) ?? context.next();
}
 
/**
 * Only returns an expression if this is not a `$store` assignment, as others can be kept as-is
 * @param {AssignmentOperator} operator
 * @param {Pattern} left
 * @param {Expression} right
 * @param {import('zimmerframe').Context<SvelteNode, ServerTransformState>} context
 * @returns {Expression | null}
 */
function build_assignment(operator, left, right, context) {
	let object = left;
 
	while (object.type === 'MemberExpression') {
		// @ts-expect-error
		object = object.object;
	}
 
	if (object.type !== 'Identifier' || !is_store_name(object.name)) {
		return null;
	}
 
	const name = object.name.slice(1);
 
	if (!context.state.scope.get(name)) {
		return null;
	}
 
	if (object === left) {
		let value = /** @type {Expression} */ (
			context.visit(build_assignment_value(operator, left, right))
		);
 
		return b.call('$.store_set', b.id(name), value);
	}
 
	return b.call(
		'$.store_mutate',
		b.assignment('??=', b.id('$$store_subs'), b.object([])),
		b.literal(object.name),
		b.id(name),
		b.assignment(
			operator,
			/** @type {Pattern} */ (context.visit(left)),
			/** @type {Expression} */ (context.visit(right))
		)
	);
}
 
/**
 * @param {string} name
 */
function is_store_name(name) {
	return name[0] === '$' && /[A-Za-z_]/.test(name[1]);
}