TSC remove comments even when removeComments to false

[AlgusDark]

TypeScript Version: 2.4.0

Code

var a = /*#__PURE__*/(function () { })()

Expected behavior:

var a = /*#__PURE__*/(function () { })();

Actual behavior:

var a = (function () { })();

If I wrote the comment above the declaration, it works, but I need that comment because is going to help me with Uglify to know that this is a pure function with no side-effects.

[kitsonk]

You mean does remove comments, correct?

The compiler does seem to erase comments in some surprising ways.

[kitsonk]

This sort of seem related to #1665 in that the compiler will erase comments where it thinks the comment is related to some code it is not emitting, but obviously it is getting a but over active in some positions.

[AlgusDark]

You're right, I edited my question. It's erasing the comments as you mention.

Ohh, I was afraid it was a bug, thanks for pointing that issue.

[nishantkagrawal]

As per #3844 using /*! should work. But it doesn't work either.

this.form['additionalName'].customValidationMessage = /*! i18nextract */ 'Some message';

while if the comment is moved to another line, it works.

this.form['additionalName'].customValidationMessage =
                /*! i18nextract */ 'Some message';

As per @yuit it was fixed, but it seems it is not fixed for all cases.

I am using typescript 2.3.4

[mhegazy]

looks like a duplicate of #17606

[mhegazy]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.

[benjamin21st]

I think I found one of the "mysterious ways" TSC would ignore the removeComments: false, see this example:
http://www.typescriptlang.org/play/#src=let%20stuff%20%3D%20%5B%0A%20%20%20%201%2C%0A%20%20%20%202%2C%0A%20%20%20%20%2F%2F%203%2C%0A%20%20%20%20%2F%2F%204%0A%5D

In case the link expires, here is the code:

let stuff = [
    1,
    2,
    // 3,
    // 4
]

The commented out lines 3 and 4 will be removed. But if one removes the trailing comma next to 2, the two lines will be preserved.

Not sure if this is a feature or bug -__-

[codemilli]

For React with typescript user, adding 'removeComments': false to ts-loader options is working rather than adding 'removeComments': false to tsconfig.json.