blocks|key|644107|text|基于Bergi回答，我提出了更通用的解决方案，使用原始assert.throws来处理错误消息：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|644108|import+assert+from+'assert';

async+function+assertThrowsAsync(fn,+regExp)+{
++let+f+=+()+=>+{};
++try+{
++++await+fn();
++}+catch(e)+{
++++f+=+()+=>+{throw+e};
++}+finally+{
++++assert.throws(f,+regExp);
++}
}|code-block|syntax|javascript|644109|用法：|644110|it('should+throw',+async+function+()+{
++++await+assertThrowsAsync(async+()+=>+await+asyncTask(),+/Error/);
});|644111|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/35782749/740245|1|https://nodejs.org/api/assert.html#assert_assert_throws_block_error_message^0|2|7|0|R|D|1|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]|$A|10|B|11|1|12]]|C|$]]|$1|D|3|E|5|F|7|13|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|14|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|15|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|16|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]|U|$5|P|Q|R|C|$S|V]]]]

Based on <a href="https://stackoverflow.com/a/35782749/740245">Bergi answer</a> I've suggest more universal solution that utilizes original <a href="https://nodejs.org/api/assert.html#assert_assert_throws_block_error_message" rel="noreferrer">assert.throws</a> for error messages:

<pre><code>import assert from 'assert';

async function assertThrowsAsync(fn, regExp) {
 let f = () =&gt; {};
 try {
 await fn();
 } catch(e) {
 f = () =&gt; {throw e};
 } finally {
 assert.throws(f, regExp);
 }
}
</code></pre>

Usage:

<pre><code>it('should throw', async function () {
 await assertThrowsAsync(async () =&gt; await asyncTask(), /Error/);
});
</code></pre>

blocks|key|347551|text|答案给了我工作，但我今天遇到了这个问题，并想出了另一个解决方案，我认为这是比较简单的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|347552|//+Code+being+tested
async+function+thisFunctionThrows()+{
++++throw+new+Error('Bad+response')
}


//+In+your+test.
try+{
++++await+thisFunctionThrows()
++++assert.equal(1+==+0)+//+Never+gets+run.+But+if+it+does+you+know+it+didn't+throw.
}+catch+(e)+{
++++assert(e.message.includes('Bad+response'))
}|code-block|syntax|javascript|347553|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

The answers given work, but I came across this issue today and came up with another solution, that I think is a little simpler.

<pre><code>// Code being tested
async function thisFunctionThrows() {
 throw new Error('Bad response')
}


// In your test.
try {
 await thisFunctionThrows()
 assert.equal(1 == 0) // Never gets run. But if it does you know it didn't throw.
} catch (e) {
 assert(e.message.includes('Bad response'))
}
</code></pre>

blocks|key|644139|text|您将希望使用assert.rejects()，它是Node.js版本10中的新版本。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|644140|在高级别，而不是assert.throws，我们需要类似于assert.rejects的东西，希望您能够接受它并运行它：|644141|++++++++const+assertRejects+=+(fn,+options)+=>+{
++++++++++++return+Promise.resolve(fn()).catch(e+=>+{
++++++++++++++++++++return+{
++++++++++++++++++++++++exception:+e,
++++++++++++++++++++++++result:+'OK'
++++++++++++++++++++}
++++++++++++++++})
++++++++++++++++.then(v+=>+{

++++++++++++++++++++if+(!(v+&&+v.result+===+'OK'))+{
++++++++++++++++++++++++return+Promise.reject('Missing+exception.');
++++++++++++++++++++}

++++++++++++++++++++if+(!options)+{
++++++++++++++++++++++++return;
++++++++++++++++++++}

++++++++++++++++++++if+(options.message)+{
++++++++++++++++++++++++//+check+options
++++++++++++++++++++}

++++++++++++++++++++console.log('here+we+check+options');

++++++++++++++++});
++++++++};

++++++++it('should+save+with+error',+async+()+=>+{

++++++++++++//+should+be+an+error+because+of+duplication+of+unique+document+(see+indexes+in+the+model)
++++++++++++return+await+assertRejects(async+()+=>+{

++++++++++++++++patientSubscriber+=+await+PatientSubscriber.create({
++++++++++++++++++++isSubscribed:+true,
++++++++++++++++++++patient:+patient._id,
++++++++++++++++++++subscriber:+user._id
++++++++++++++++});

++++++++++++},+{
++++++++++++++++message:+/PatientSubscriber+validation+failed/
++++++++++++});

++++++++});|code-block|syntax|javascript|644142|entityMap^0|6|G|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

You are going to want to use, <code>assert.rejects()</code> which is new in Node.js version 10.

At the high level, instead of assert.throws, we want something like assert.rejects, hopefully you can take this and run with it:

<pre><code> const assertRejects = (fn, options) =&gt; {
 return Promise.resolve(fn()).catch(e =&gt; {
 return {
 exception: e,
 result: 'OK'
 }
 })
 .then(v =&gt; {

 if (!(v &amp;&amp; v.result === 'OK')) {
 return Promise.reject('Missing exception.');
 }

 if (!options) {
 return;
 }

 if (options.message) {
 // check options
 }

 console.log('here we check options');

 });
 };

 it('should save with error', async () =&gt; {

 // should be an error because of duplication of unique document (see indexes in the model)
 return await assertRejects(async () =&gt; {

 patientSubscriber = await PatientSubscriber.create({
 isSubscribed: true,
 patient: patient._id,
 subscriber: user._id
 });

 }, {
 message: /PatientSubscriber validation failed/
 });

 });
</code></pre>

blocks|key|644181|text|由于这个问题仍然受到关注，我想总结两个最好的解决方案，特别是突出新的标准方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|644182|节点v10%2B|644183|断言库中有一个专用的方法，assert.rejects。|offset|length|style|CODE|644184|对于较早版本的Node|644185|来自vitalets回答的填充|644186|import+assert+from+'assert';

async+function+assertThrowsAsync(fn,+regExp)+{
++let+f+=+()+=>+{};
++try+{
++++await+fn();
++}+catch(e)+{
++++f+=+()+=>+{throw+e};
++}+finally+{
++++assert.throws(f,+regExp);
++}
}|code-block|syntax|javascript|644187|entityMap|0|LINK|mutability|MUTABLE|url|https://nodejs.org/api/assert.html#assert_assert_rejects_asyncfn_error_message|1|https://stackoverflow.com/a/46957474/3115520^0|0|0|D|E|D|E|0|0|0|2|A|1|0|0^^$0|@$1|2|3|4|5|6|7|12|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|13|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|14|8|@$F|15|G|16|H|I]]|9|@$F|17|G|18|1|19]]|A|$]]|$1|J|3|K|5|6|7|1A|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|1B|8|@]|9|@$F|1C|G|1D|1|1E]]|A|$]]|$1|N|3|O|5|P|7|1F|8|@]|9|@]|A|$Q|R]]|$1|S|3|-4|5|6|7|1G|8|@]|9|@]|A|$]]]|T|$U|$5|V|W|X|A|$Y|Z]]|10|$5|V|W|X|A|$Y|11]]]]

Since the question is still getting attention, I'd like to sum up the two best solutions, especially to highlight the new standard method.

<h2>Node v10+</h2>

There's a dedicated method in the assert library, <a href="https://nodejs.org/api/assert.html#assert_assert_rejects_asyncfn_error_message" rel="nofollow noreferrer"><code>assert.rejects</code></a>.

<h2>For older versions of Node</h2>

A fill from <a href="https://stackoverflow.com/a/46957474/3115520">vitalets answer</a>:

<pre><code>import assert from 'assert';

async function assertThrowsAsync(fn, regExp) {
 let f = () =&gt; {};
 try {
 await fn();
 } catch(e) {
 f = () =&gt; {throw e};
 } finally {
 assert.throws(f, regExp);
 }
}
</code></pre>

I want to check if an async function throws using <a href="https://nodejs.org/api/assert.html#assert_assert_throws_fn_error_message" rel="noreferrer"><code>assert.throws</code></a> from the native <code>assert</code> module.
I tried with
<pre><code>const test = async () =&gt; await aPromise();
assert.throws(test); // AssertionError: Missing expected exception..
</code></pre>
It (obviously?) doesn't work because the function exits before the Promise is resolved.
Yet I found <a href="https://stackoverflow.com/questions/19187111/assert-throws-on-asynchronous-method">this question</a> where the same thing is attained using callbacks.
Any suggestion?
(I'm transpiling to Node.js native generators using Babel.)

Node.js assert.throws with async functions (Promises)

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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问带有异步函数的Node.js assert.throws (承诺)
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