eslint-plugin-ft-flow/dist/rules/noMutableArray.js.flow

Flowtype linting rules for ESLint by flow-typed

import _ from 'lodash';

const schema = [];

// const x = [];
const isEmptyArrayLiteral = (node) => _.get(node, 'init.type') === 'ArrayExpression' && _.get(node, 'init.elements.length') === 0;

// const x = new Array(); const y = Array();
const isEmptyArrayInstance = (node) => {
  if (_.get(node, 'init.type') === 'NewExpression' || _.get(node, 'init.type') === 'CallExpression') {
    return _.get(node, 'init.callee.name') === 'Array' && _.get(node, 'init.arguments.length') === 0;
  }

  return false;
};

const isAnnotationOfEmptyArrayInit = (node) => {
  if (_.has(node, 'parent.parent.parent')) {
    const parent = _.get(node, 'parent.parent.parent');
    const isVariableDeclaration = _.get(parent, 'type') === 'VariableDeclarator';

    return isVariableDeclaration && (isEmptyArrayLiteral(parent) || isEmptyArrayInstance(parent));
  }

  return false;
};

const create = (context) => ({
  ArrayTypeAnnotation(node) {
    if (!isAnnotationOfEmptyArrayInit(node)) {
      context.report({
        fix(fixer) {
          const rawElementType = context.getSourceCode().getText(node.elementType);

          return fixer.replaceText(node, `$ReadOnlyArray<${rawElementType}>`);
        },
        message: 'Use "$ReadOnlyArray" instead of array shorthand notation',
        node,
      });
    }
  },
  GenericTypeAnnotation(node) {
    if (node.id.name === 'Array' && !isAnnotationOfEmptyArrayInit(node)) {
      context.report({
        fix(fixer) {
          return fixer.replaceText(node.id, '$ReadOnlyArray');
        },
        message: 'Use "$ReadOnlyArray" instead of "Array"',
        node,
      });
    }
  },
});

export default {
  create,
  meta: {
    fixable: 'code',
    schema,
  },
};