v12 regression; gentype of record with escaped record fields generates invalid Typescript code

[illusionalsagacity]

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• Is it a bug? Usage questions should often be asked in the forum instead.
• Concise, focused, friendly issue title & description.
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• Is it already fixed in master? Instructions

The following rescript code

@genType
type t = {
  \"Illegal-field name": int,
}

results in this:

export type record = {
  readonly "\"Illegal-field name"": number
};

The extra trailing " makes this invalid syntax, and the leading \" doesn't match the generated javascript