node-param-array-type-assertion.ts

import { AST_NODE_TYPES, TSESTree } from "@typescript-eslint/utils";
import { utils } from "../ast/utils";
import { id } from "../ast/identifiers";

export default utils.createRule({
	name: utils.getRuleName(module),
	meta: {
		type: "problem",
		docs: {
			description: "Array of node parameters must be typed, not type-asserted.",
			recommended: "strict",
		},
		fixable: "code",
		schema: [],
		messages: {
			typeArray: "Use ': INodeProperties[]' [autofixable]",
		},
	},
	defaultOptions: [],
	create(context) {
		return {
			TSAsExpression(node) {
				if (containsArrayOfNodeParams(node)) {
					if (
						node.parent?.type !== AST_NODE_TYPES.VariableDeclarator ||
						node.parent?.id.type !== AST_NODE_TYPES.Identifier
					) {
						return;
					}

					const rangeToRemove = utils.getRangeToRemove({
						ast: node.typeAnnotation,
					});

					const { range } = node.parent.id;

					if (!range) return null;

					const indentation = getTrailingBracketIndentation(node);

					context.report({
						messageId: "typeArray",
						node,
						fix: (fixer) => {
							// double fix
							return [
								fixer.replaceTextRange(rangeToRemove, indentation),
								fixer.insertTextAfterRange(range, ": INodeProperties[]"),
							];
						},
					});
				}
			},
		};
	},
});

function containsArrayOfNodeParams(node: TSESTree.TSAsExpression) {
	if (
		node.expression.type !== AST_NODE_TYPES.ArrayExpression ||
		node.expression.elements.length === 0
	) {
		return false;
	}

	return node.expression.elements.every((element) => {
		return (
			element?.type === AST_NODE_TYPES.ObjectExpression &&
			id.isNodeParameter(element)
		);
	});
}

function getTrailingBracketIndentation(node: TSESTree.TSAsExpression) {
	return "\t".repeat(node.expression.loc.end.column - 1); // `- 1` to remove bracket column
}