65 lines
1.9 KiB
JavaScript
65 lines
1.9 KiB
JavaScript
'use strict'
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const getDocsUrl = require('./lib/get-docs-url')
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module.exports = {
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meta: {
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docs: {
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url: getDocsUrl('prefer-await-to-callbacks')
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},
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messages: {
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error: 'Avoid callbacks. Prefer Async/Await.'
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}
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},
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create(context) {
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function checkLastParamsForCallback(node) {
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const lastParam = node.params[node.params.length - 1] || {}
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if (lastParam.name === 'callback' || lastParam.name === 'cb') {
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context.report({ node: lastParam, messageId: 'error' })
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}
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}
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function isInsideYieldOrAwait() {
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return context.getAncestors().some(parent => {
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return (
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parent.type === 'AwaitExpression' || parent.type === 'YieldExpression'
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)
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})
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}
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return {
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CallExpression(node) {
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// Callbacks aren't allowed.
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if (node.callee.name === 'cb' || node.callee.name === 'callback') {
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context.report({ node, messageId: 'error' })
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return
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}
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// Then-ables aren't allowed either.
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const args = node.arguments
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const lastArgIndex = args.length - 1
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const arg = lastArgIndex > -1 && node.arguments[lastArgIndex]
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if (
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(arg && arg.type === 'FunctionExpression') ||
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arg.type === 'ArrowFunctionExpression'
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) {
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// Ignore event listener callbacks.
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if (
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node.callee.property &&
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(node.callee.property.name === 'on' ||
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node.callee.property.name === 'once')
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) {
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return
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}
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if (arg.params && arg.params[0] && arg.params[0].name === 'err') {
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if (!isInsideYieldOrAwait()) {
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context.report({ node: arg, messageId: 'error' })
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}
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}
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}
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},
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FunctionDeclaration: checkLastParamsForCallback,
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FunctionExpression: checkLastParamsForCallback,
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ArrowFunctionExpression: checkLastParamsForCallback
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}
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}
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}
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