javascript - Bluebird 忘记返回警告丢失

Question

我期待 Bluebird forgotten return warning出现，但由于某种原因它不起作用。

A demo :

const Bluebird = require('bluebird');

Bluebird.config({
    warnings: true
})

Bluebird.resolve(1)
.then(() => {
    Bluebird.resolve(2); // should warn about forgotten return
})
.then(two => console.log(two));

如何解决输出警告？

我怀疑我以前遇到过这个问题，但我不记得解决方案是什么。

Answer 1

似乎需要启用长堆栈跟踪才能显示警告。您可以使用配置对象来启用它们 ( docs ) ( demo ):

Bluebird.config({
    warnings: true,
    longStackTraces: true
});

或环境变量 ( docs ) ( demo ):

In Node.js you may configure warnings and long stack traces for the entire process using environment variables:

BLUEBIRD_LONG_STACK_TRACES=1 BLUEBIRD_WARNINGS=1 node app.js

Both features are automatically enabled if the BLUEBIRD_DEBUG environment variable has been set or if the NODE_ENV environment variable is equal to "development".

和

To enable long stack traces and warnings in node development:

$ NODE_ENV=development node server.js

To enable long stack traces and warnings in node production:

$ BLUEBIRD_DEBUG=1 node server.js

See Environment Variables.

---

编辑为什么这是必要的:

似乎默认情况下警告和长堆栈跟踪都是禁用的，并且仅在检测到开发环境时才启用，请参阅 here :

Note that even though false is the default here, a development environment might be detected which automatically enables long stack traces and warnings.

要在生产环境中显示警告，您不仅必须启用警告，还必须启用长堆栈跟踪，请参阅 here和 here .