electron/lib/common/api/deprecate.js
Shelley Vohr 4b18a38e9f
chore: simplify promisify helper (#15952)
chore: simplify promisify helper
2018-12-10 08:13:09 -08:00

122 lines
3.1 KiB
JavaScript

'use strict'
let deprecationHandler = null
function warnOnce (oldName, newName) {
let warned = false
const msg = newName
? `'${oldName}' is deprecated and will be removed. Please use '${newName}' instead.`
: `'${oldName}' is deprecated and will be removed.`
return () => {
if (!warned && !process.noDeprecation) {
warned = true
deprecate.log(msg)
}
}
}
const deprecate = {
setHandler: (handler) => { deprecationHandler = handler },
getHandler: () => deprecationHandler,
warn: (oldName, newName) => {
if (!process.noDeprecation) {
deprecate.log(`'${oldName}' is deprecated. Use '${newName}' instead.`)
}
},
log: (message) => {
if (typeof deprecationHandler === 'function') {
deprecationHandler(message)
} else if (process.throwDeprecation) {
throw new Error(message)
} else if (process.traceDeprecation) {
return console.trace(message)
} else {
return console.warn(`(electron) ${message}`)
}
},
event: (emitter, oldName, newName) => {
const warn = newName.startsWith('-') /* internal event */
? warnOnce(`${oldName} event`)
: warnOnce(`${oldName} event`, `${newName} event`)
return emitter.on(newName, function (...args) {
if (this.listenerCount(oldName) !== 0) {
warn()
this.emit(oldName, ...args)
}
})
},
removeProperty: (o, removedName) => {
// if the property's already been removed, warn about it
if (!(removedName in o)) {
deprecate.log(`Unable to remove property '${removedName}' from an object that lacks it.`)
}
// wrap the deprecated property in an accessor to warn
const warn = warnOnce(removedName)
let val = o[removedName]
return Object.defineProperty(o, removedName, {
configurable: true,
get: () => {
warn()
return val
},
set: newVal => {
warn()
val = newVal
}
})
},
promisify: (fn, cbParamIndex) => {
const fnName = fn.name || 'function'
const oldName = `${fnName} with callbacks`
const newName = `${fnName} with Promises`
const warn = warnOnce(oldName, newName)
return function (...params) {
const cb = params.splice(cbParamIndex, 1)[0]
const promise = fn.apply(this, params)
if (typeof cb !== 'function') return promise
if (process.enablePromiseAPIs) warn()
return promise
.then(res => {
process.nextTick(() => {
cb(null, res)
})
}, err => {
process.nextTick(() => {
cb(err)
})
})
}
},
renameProperty: (o, oldName, newName) => {
const warn = warnOnce(oldName, newName)
// if the new property isn't there yet,
// inject it and warn about it
if ((oldName in o) && !(newName in o)) {
warn()
o[newName] = o[oldName]
}
// wrap the deprecated property in an accessor to warn
// and redirect to the new property
return Object.defineProperty(o, oldName, {
get: () => {
warn()
return o[newName]
},
set: value => {
warn()
o[newName] = value
}
})
}
}
module.exports = deprecate