[JSON] Trailing comments are not handled

We use the js expression parser (which shares the same printer with JSON) to parse binding syntax in HTML, but the trailing comments are removed (reported by https://github.com/prettier/prettier/pull/5259#issuecomment-429571079).

Prettier 1.14.3 Playground link

--parser json

Input:

index /* TODO: use id when links will be provided by API */

Output:

Error: Comment "TODO: use id when links will be provided by API" was not printed. Please report this error!
    at https://prettier.io/lib/standalone.js:10671:13
    at Array.forEach (<anonymous>)
    at ensureAllCommentsPrinted (https://prettier.io/lib/standalone.js:10669:15)
    at coreFormat (https://prettier.io/lib/standalone.js:10719:3)
    at format (https://prettier.io/lib/standalone.js:10874:16)
    at formatWithCursor (https://prettier.io/lib/standalone.js:10886:12)
    at https://prettier.io/lib/standalone.js:21134:15
    at Object.format (https://prettier.io/lib/standalone.js:21142:12)
    at formatCode (https://prettier.io/worker.js:188:21)
    at handleMessage (https://prettier.io/worker.js:139:18)

Expected behavior: Comments are printed.

[ikatyang]

@michaeljota It’s indeed a vue-only issue after we switch to use angular-estree-parser for angular expression.

(Angular only allows a single-line comment at the end of the expression, excluding microsyntax.)

[renatoagds]

@ikatyang hey! I didn’t start it. go ahead 🤘