Line returns added in serialized function when running through jest

issue に記載されている Jest テストの再現から始め、その出力をスタンドアロンの Node.js の結果およびリンク先の gist と比較します。Jest を通して実行したときに、シリアライズされた例が改行を挿入せず、期待される関数のフォーマットを生成すれば完了です。

I always get the weirdest issues. So, serialize-javascript works fine in actual production, but it somehow outputs a different thing while running a test. In the example of the object with all the types including the function, I get an odd line return within the serialized function.

Environment:

• Node 14.13.0
• Jest 26.5.2
• serialize-javascript 5.0.1

Reproduction:
(Alternatively, see https://gist.github.com/eslachance/6dbd88820f09de4509d4f19c4c0e7ad6 for reproduction)

• Create a jest test
• import serialize-javascript
• Add a console.log of the serialized example.

test("serializes javascript", () => {
  console.log(serialize({
    str  : 'string',
    num  : 0,
    obj  : {foo: 'foo'},
    arr  : [1, 2, 3],
    bool : true,
    nil  : null,
    undef: undefined,
    inf  : Infinity,
    date : new Date("Thu, 28 Apr 2016 22:02:17 GMT"),
    map  : new Map([['hello', 'world']]),
    set  : new Set([123, 456]),
    fn   : function echo(arg) { return arg; },
    re   : /([^\s]+)/g,
    big  : BigInt(10),
  }))
});

Expected result:

{"str":"string","num":0,"obj":{"foo":"foo"},"arr":[1,2,3],"bool":true,"nil":null,"undef":undefined,"inf":Infinity,"date":new Date("2016-04-28T22:02:17.000Z"),"map":new Map([["hello","world"]]),"set":new Set([123,456]),"fn":function echo(arg) { return arg; },"re":new RegExp("([^\\s]+)", "g"),"big":BigInt("10")}

Actual Result:

    {"str":"string","num":0,"obj":{"foo":"foo"},"arr":[1,2,3],"bool":true,"nil":null,"undef":undefined,"inf":Infinity,"date":new Date("2016-04-28T22:02:17.000Z"),"map":new Map([["hello","world"]]),"set":new Set([123,456]),"fn":function echo(arg) {
          return arg;
        },"re":new RegExp("([^\\s]+)", "g"),"big":BigInt("10")}

The expected result was a simple nodejs file which outputs the serialized data and nothing else.

This is confusing me very much, and I don't know where to begin in troubleshooting it.