await-async-queries.ts

import { ASTUtils, TSESTree } from '@typescript-eslint/utils';

import { createTestingLibraryRule } from '../create-testing-library-rule';
import {
	findClosestCallExpressionNode,
	getDeepestIdentifierNode,
	getFunctionName,
	getInnermostReturningFunction,
	getVariableReferences,
	isPromiseHandled,
} from '../node-utils';

export const RULE_NAME = 'await-async-queries';
export type MessageIds = 'asyncQueryWrapper' | 'awaitAsyncQuery';
type Options = [];

export default createTestingLibraryRule<Options, MessageIds>({
	name: RULE_NAME,
	meta: {
		type: 'problem',
		docs: {
			description: 'Enforce promises from async queries to be handled',
			recommendedConfig: {
				dom: 'error',
				angular: 'error',
				react: 'error',
				vue: 'error',
				svelte: 'error',
				marko: 'error',
			},
		},
		messages: {
			awaitAsyncQuery:
				'promise returned from `{{ name }}` query must be handled',
			asyncQueryWrapper:
				'promise returned from `{{ name }}` wrapper over async query must be handled',
		},
		schema: [],
	},
	defaultOptions: [],

	create(context, _, helpers) {
		const functionWrappersNames: string[] = [];

		function detectAsyncQueryWrapper(node: TSESTree.Identifier) {
			const innerFunction = getInnermostReturningFunction(context, node);
			if (innerFunction) {
				functionWrappersNames.push(getFunctionName(innerFunction));
			}
		}

		return {
			CallExpression(node) {
				const identifierNode = getDeepestIdentifierNode(node);

				if (!identifierNode) {
					return;
				}

				if (helpers.isAsyncQuery(identifierNode)) {
					// detect async query used within wrapper function for later analysis
					detectAsyncQueryWrapper(identifierNode);

					const closestCallExpressionNode = findClosestCallExpressionNode(
						node,
						true
					);

					if (!closestCallExpressionNode?.parent) {
						return;
					}

					const references = getVariableReferences(
						context,
						closestCallExpressionNode.parent
					);

					// check direct usage of async query:
					// const element = await findByRole('button')
					if (references.length === 0) {
						if (!isPromiseHandled(identifierNode)) {
							context.report({
								node: identifierNode,
								messageId: 'awaitAsyncQuery',
								data: { name: identifierNode.name },
							});
							return;
						}
					}

					// check references usages of async query:
					//  const promise = findByRole('button')
					//  const element = await promise
					for (const reference of references) {
						if (
							ASTUtils.isIdentifier(reference.identifier) &&
							!isPromiseHandled(reference.identifier)
						) {
							context.report({
								node: identifierNode,
								messageId: 'awaitAsyncQuery',
								data: { name: identifierNode.name },
							});
							return;
						}
					}
				} else if (
					functionWrappersNames.includes(identifierNode.name) &&
					!isPromiseHandled(identifierNode)
				) {
					// check async queries used within a wrapper previously detected
					context.report({
						node: identifierNode,
						messageId: 'asyncQueryWrapper',
						data: { name: identifierNode.name },
					});
				}
			},
		};
	},
});