assert.ifError(value)

• value <any>

如果 value 不是 undefined 或 null,则抛出 value。这在回调中测试 error 参数时很有用。堆栈跟踪包含来自传给 ifError() 的错误的所有帧,包括 ifError() 本身的潜在新帧。

\Throws value if value is not undefined or null. This is useful when testing the error argument in callbacks. The stack trace contains all frames from the error passed to ifError() including the potential new frames for ifError() itself.

import assert from 'node:assert/strict';
assert.ifError(null);
// OK
assert.ifError(0);
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 0
assert.ifError('error');
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 'error'
assert.ifError(new Error());
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: Error
// Create some random error frames.
let err;
(function errorFrame() {
 err = new Error('test error');
})();
(function ifErrorFrame() {
 assert.ifError(err);
})();
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: test error
// at ifErrorFrame
// at errorFrameconst assert = require('node:assert/strict');
assert.ifError(null);
// OK
assert.ifError(0);
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 0
assert.ifError('error');
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 'error'
assert.ifError(new Error());
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: Error
// Create some random error frames.
let err;
(function errorFrame() {
 err = new Error('test error');
})();
(function ifErrorFrame() {
 assert.ifError(err);
})();
// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: test error
// at ifErrorFrame
// at errorFrame拷贝