Playgrounds rejects valid Rust (due to input processing?)

This code is expected to work but generates a compiler error due to a comment:
https://play.rust-lang.org/?version=nightly&mode=debug&edition=2018&gist=45b03c2e33ff3b6c20af40794c505c92

   Compiling playground v0.0.1 (/playground)
error: this file contains an un-closed delimiter
 --> src/main.rs:1:1854
  |
1 | pub fn main() {
    let reserved_names: [&str; 103] = [
        "as",
        "break",
        "const",
(snip)

If rust-playground tries to put all the code on a single line, that's likely the problem. Thanks for building and maintaining such a useful tool; much appreciated!

Start with the linked Rust Playground gist and compare the source sent to the compiler with the original formatting, especially around the comment that triggers the un-closed-delimiter error. Trace the playground's input-processing path to identify where valid Rust is altered; done means the linked example compiles successfully without the delimiter error.