Escape single-lined description in SDL

[barthez]

Hello!

I got a pretty strange error while generating types for typescript out of schema SDL. I have switched from rendering with https://github.com/maartenvanvliet/absinthe_sdl to Absinthe.Schema.to_sdl. It turned out I had a macro enum definition like this:

enum :logic do
  value :and, description: "Apply \"and\" logic to query"
  value :or, description: "Apply \"or\" logic to query"
end

The type generator complained about duplicated values in enum. When I took a closer look at generated SDL it looked like:

enum Logic {
  "Apply "and" logic to query"
  AND

  "Apply "or" logic to query"
  OR
}

Which, after stripping descriptions, is:

enum Logic {
  and
  AND
  or
  OR
}

I got into GraphQL specs for strings: http://spec.graphql.org/June2018/#sec-String-Value

It seems some characters need to be escaped in a single line description string.

[barthez]

Hey @benwilson512, could you please give it a look?

[benwilson512]

Great catch, thanks!