Wsrtjtyk

I have the following code where defining a getByIds function that filters an array of objects, each of which has an id field and other fields.

// @flow



type X = {

  id: string

};

type F = (Array<string>, Array<X>) => Array<X>;

import { curry } from "ramda";

const getByIds: F = curry((ids, xs) => xs.filter(x => ids.includes(x.id)));



export default getByIds;

when feeding a user = {id: 123, alias: 'foo'} to getByIds, flow warns that X doesn't have property alias . I thought flow allows extra properties (covariant?) to be attached to object of a less restricting type.

Here is the eslintrc.js

    module.exports = {

        env: {

            // browser: true ensures things like window, or localStorage won't get complained

            browser: true,

            es6: true

        },

        plugins: [

            "react",

            "flowtype"

            // "prettier",

        ],

        extends: [

            "eslint:recommended",

            // "plugin:react/recommended",

            "plugin:flowtype/recommended"

        ],

        // https://github.com/feross/standard/issues/447

        parser: "babel-eslint",



        parserOptions: {

            ecmaFeatures: {

                modules: true,

                classes: true,

                experimentalObjectRestSpread: true,

                jsx: true

            },

            sourceType: "module"

        },

        rules: {

            // "indent": [

            //     "error",

            //     4

            // ],



            // "prettier/prettier": "error",

            "linebreak-style": ["error", "unix"],

            // "quotes": [

            //     "error",

            //     "double"

            // ],

            // "semi": [

            //     "error",

            //     "never"

            // ],

            // "jsx-space-before-closing": 1,

            // "no-undef": "error",

            "no-unused-vars": [2, { argsIgnorePattern: "_" }], //https://eslint.org/docs/rules/no-unused-vars#argsignorepattern

            "flowtype/define-flow-type": 1,

            "comma-dangle": [1, "always-multiline"],

            "always-multiline": 0,

            "no-console": 0,

            "no-constant-condition": 0,

            "no-case-declarations": 0,

            "react/no-danger": 0,

            "react/display-name": 1,

            "react/jsx-key": 1,

            "react/jsx-no-comment-textnodes": 1,

            "react/jsx-no-duplicate-props": 1,

            "react/jsx-no-target-blank": 1,

            "react/jsx-no-undef": 1,

            "react/jsx-uses-react": 1,

            "react/jsx-uses-vars": 1,

            "react/no-children-prop": 1,

            "react/no-danger-with-children": 1,

            "react/no-deprecated": 1,

            "react/no-direct-mutation-state": 1,

            "react/no-find-dom-node": 1,

            "react/no-is-mounted": 1,

            "react/no-render-return-value": 1,

            "react/no-string-refs": 1,

            "react/no-unescaped-entities": 1,

            "react/no-unknown-property": 1,

            "react/prop-types": 1,

            "react/react-in-jsx-scope": 1,

            "react/require-render-return": 1,

            "react/jsx-max-props-per-line": 1,

            "react/jsx-first-prop-new-line": [1, "multiline-multiprop"],

            "react/jsx-indent-props": [1, 2]

        },

        globals: {

            module: true,

            gon: true,

            require: true,

            __dirname: true,

            _: true,

            jest: true,

            process: true,

            it: true,

            describe: true,

            expect: true,

            test: true,

            SyntheticEvent: true,

            SyntheticAnimationEvent: true,

            SyntheticClipboardEvent: true,

            SyntheticCompositionEvent: true,

            SyntheticInputEvent: true,

            SyntheticUIEvent: true,

            SyntheticFocusEvent: true,

            SyntheticKeyboardEvent: true,

            SyntheticMouseEvent: true,

            SyntheticDragEvent: true,

            SyntheticWheelEvent: true,

            SyntheticTouchEvent: true,

            SyntheticTransitionEvent: true

        },

        settings: {

            flowtype: {

                onlyFilesWithFlowAnnotation: true

            }

        }

    };

Any ideas?