eslint-plugin-unicorn-x/rules/no-named-default.js

More than 100 powerful ESLint rules

import {removeSpecifier} from './fix/index.js';
import assertToken from './utils/assert-token.js';

const MESSAGE_ID = 'no-named-default';
const messages = {
	[MESSAGE_ID]: 'Prefer using the default {{type}} over named {{type}}.',
};

const isValueImport = (node) => !node.importKind || node.importKind === 'value';
const isValueExport = (node) => !node.exportKind || node.exportKind === 'value';

const fixImportSpecifier = (importSpecifier, {sourceCode}) =>
	function* (fixer) {
		const declaration = importSpecifier.parent;

		yield* removeSpecifier(
			importSpecifier,
			fixer,
			sourceCode,
			/* keepDeclaration */ true,
		);

		const nameText = sourceCode.getText(importSpecifier.local);
		const hasDefaultImport = declaration.specifiers.some(
			({type}) => type === 'ImportDefaultSpecifier',
		);

		// Insert a new `ImportDeclaration`
		if (hasDefaultImport) {
			const fromToken = sourceCode.getTokenBefore(
				declaration.source,
				(token) => token.type === 'Identifier' && token.value === 'from',
			);
			const [startOfFromToken] = sourceCode.getRange(fromToken);
			const [, endOfDeclaration] = sourceCode.getRange(declaration);
			const text = `import ${nameText} ${sourceCode.text.slice(startOfFromToken, endOfDeclaration)}`;
			yield fixer.insertTextBefore(declaration, `${text}\n`);

			return;
		}

		const importToken = sourceCode.getFirstToken(declaration);
		assertToken(importToken, {
			expected: {type: 'Keyword', value: 'import'},
			ruleId: 'no-named-default',
		});

		const shouldAddComma = declaration.specifiers.some(
			(specifier) =>
				specifier !== importSpecifier &&
				specifier.type === importSpecifier.type,
		);
		yield fixer.insertTextAfter(
			importToken,
			` ${nameText}${shouldAddComma ? ',' : ''}`,
		);
	};

const fixExportSpecifier = (exportSpecifier, {sourceCode}) =>
	function* (fixer) {
		const declaration = exportSpecifier.parent;
		yield* removeSpecifier(exportSpecifier, fixer, sourceCode);

		const text = `export default ${sourceCode.getText(exportSpecifier.local)};`;
		yield fixer.insertTextBefore(declaration, `${text}\n`);
	};

/** @param {import('eslint').Rule.RuleContext} context */
const create = (context) => ({
	ImportSpecifier(specifier) {
		if (
			!(
				isValueImport(specifier) &&
				specifier.imported.name === 'default' &&
				isValueImport(specifier.parent)
			)
		) {
			return;
		}

		return {
			node: specifier,
			messageId: MESSAGE_ID,
			data: {type: 'import'},
			fix: fixImportSpecifier(specifier, context),
		};
	},
	ExportSpecifier(specifier) {
		if (
			!(
				isValueExport(specifier) &&
				specifier.exported.name === 'default' &&
				isValueExport(specifier.parent) &&
				!specifier.parent.source
			)
		) {
			return;
		}

		return {
			node: specifier,
			messageId: MESSAGE_ID,
			data: {type: 'export'},
			fix: fixExportSpecifier(specifier, context),
		};
	},
});

/** @type {import('eslint').Rule.RuleModule} */
const config = {
	create,
	meta: {
		type: 'suggestion',
		docs: {
			description: 'Disallow named usage of default import and export.',
			recommended: true,
		},
		fixable: 'code',
		messages,
	},
};

export default config;