eslint-config-strictest
Version:
Super strict eslint rules for more reliable software
130 lines (114 loc) • 4.18 kB
JavaScript
module.exports = {
rules: {
// 🕸
'@typescript-eslint/require-array-sort-compare': 'error',
// 👀
'@typescript-eslint/prefer-reduce-type-parameter': 'error',
'@typescript-eslint/return-await': ['error', 'always'],
'@typescript-eslint/dot-notation': 'error',
/**
* #high, #improves-code-stability, #improves-code-understanding
* Bad: `if (value)`, Good: `if (value !== undefined)`
*/
'@typescript-eslint/strict-boolean-expressions': ['error'],
/**
* #high, #improves-code-stability, #improves-code-understanding
* Bad: `return foo !== null && foo !== undefined ? foo : 'a string'`
* Good: `foo ?? 'a string'`
*/
'@typescript-eslint/prefer-nullish-coalescing': 'error',
/**
* #improves-code-stability, #improves-code-understanding
* Mark all functions that return a Promise as `async`. This clearly shows all asynchronous
* functions and ensures you can't return a non-Promise value.
*/
'@typescript-eslint/promise-function-async': [
'error',
{
checkArrowFunctions: false,
},
],
/**
* #improves-code-stability
* Warns about properties that can be readonly but aren't.
* Improves code stability because it warns users when trying to turn a readonly property into a
* mutable one.
*/
'@typescript-eslint/prefer-readonly': 'error',
/**
* #improves-code-stability
* Allow only strings and numbers to be placed in template expressions.
* Bad: `${null}`, Bad: `${[]}`
* Good: `${'string'}`, Good: `${4}`
*/
'@typescript-eslint/restrict-template-expressions': [
'error',
{
allowNumber: true,
},
],
/**
* #improves-code-understanding
* Bad: `array.indexOf(value) !== -1`, Good: `array.includes(values)`
*/
'@typescript-eslint/prefer-includes': 'error',
/**
* #improves-code-understanding
* Bad: `array[array.length - 1] === '.'`, Good: `array.endsWith('.')`
*/
'@typescript-eslint/prefer-string-starts-ends-with': 'error',
/**
* #improves-code-understanding
* Bad: `'' + {}`
* Bad: ({}.toString())
* Good: 'Text' + true
* Good: `Arrays too: ${[1, 2, 3]}`
*/
'@typescript-eslint/no-base-to-string': 'error',
/**
* #improves-code-understanding
* ```ts
* // Bad
* const func = () => 'value'
* await func()
*
* // Good
* const func = async () => 'value'
* await func()
* ```
*/
'@typescript-eslint/await-thenable': 'error',
/**
* #remove-unnecessary, #improves-code-understanding
* Bad: `const value = 3 as number`, Good: `const value = 3`
*/
'@typescript-eslint/no-unnecessary-type-assertion': 'error',
/**
* #remove-unnecessary, #improves-code-understanding
* @example
* // Bad
* function f<T = number>() {}
* f<number>();
* // Good
* function f<T = number>() {}
* f<string>();
*/
'@typescript-eslint/no-unnecessary-type-arguments': 'error',
/**
* #remove-unnecessary, #improves-code-understanding
* Asynchronous functions that don’t use await might not need to be asynchronous functions and
* could be the unintentional result of refactoring.
*/
'@typescript-eslint/require-await': 'error',
/**
* #ban, #low
* Don't use `for-in` loops for arrays.
* Bad: `for (const x in [3, 4, 5]) {`, Good: `for (const x in { a: 3, b: 4, c: 5 }) {`
*/
'@typescript-eslint/no-for-in-array': 'error',
/**
* #consistency, #low
*/
'@typescript-eslint/no-unnecessary-qualifier': 'error',
},
}