fix output escaping

[3axap4eHko]

During a conversion process via command

jss convert style.css -f js -e cjs > style.js

escaping characters should be escaped:

#big-bang::before {
  content: "\ffff";
}

should became

#big-bang::before {
  content: "\\ffff";
}

[kof]

Do you foresee any problems with other properties besides content, e.g. background image URLs?

[3axap4eHko]

@kof every backslash should be escaped, otherwise, it's used as an escape character and escapes the next character. Does it make sense for you?

[kof]

yeah, anyways I am gonna merge it and we will see

[kof]

Actually, it only makes sense if the escaping character is inside of a string value, like in case of content. Other properties may have actual character escape, which you would unescape.

[kof]

I think ultimately we should movecss parser we currently use to postcss parser and add value parser plugin, which will be context aware, otherwise this kind of fixes will be an infinite source of bugs.

[3axap4eHko]

The other properties within the actual escape character are not affected because the escape character is not represented by a backslash.

[3axap4eHko]

@kof Could you give me an example of values that you were mentioning before?

[kof]

Literally any value that potentially is escaped, so the backslash is actually escaping and doesn't need unescaping. Can be content, can be url

[kof]

content: "test \"bla\"";

[3axap4eHko]

content: "test \"bla\"";

At this case, my fix transpiles it to '"test \\"bla\\""' and once you set a css rule it converts back to "test \"bla\"" as a js expression

[kof]

yea but it is supposed to render test "bla" in the end, right?

[3axap4eHko]

nope, just test it out on own example

[3axap4eHko]

@kof ping 😃

[3axap4eHko]

actually I can add this example too

[maksym-boytsov]

I faced the same problem, tested on my example, and for me, it works well.
@kof I think that current PR solving the escaping problem