JavaScript only has a single number type, so 0.0 is the same as 0. Thus when you are sending a JS object as JSON, in certain situations it will literally change 0.0 to 0 for you and send that instead (same with any number that has a zero decimal). This will cause casting errors in other languages when they attempt to deserialize ints into doubles or floats.
It will cause casting errors in other languages that have badly written, non-standards compliant, JSON parsers, as 1 and 1.0 being the same is part of the official JSON ISO standard and has been for a long time: https://json-schema.org/understanding-json-schema/reference/numeric
JSON schema is not a standard lol. 😂 it especially isn’t a standard across languages. And it most definitely isn’t an ISO standard 🤣. JSON Data Interchange Format is a standard, but it wasn’t published until 2017, and it doesn’t say anything about 1.0 needs to auto cast to 1 (because that would be fucking idiotic). https://datatracker.ietf.org/doc/html/rfc8259
JSON Schema does have a draft in the IETF right now, but JSON Schema isn’t a specification of the language, it’s for defining a schema for your code. https://datatracker.ietf.org/doc/draft-handrews-json-schema/
Edit: and to add to that, JavaScript has a habit of declaring their dumb bugs as “it’s in the spec” years after the fact. Just because it’s in the spec doesn’t mean it’s not a bug and just because it’s in the spec doesn’t mean everywhere else is incorrect.
Yes, it most literally and inarguably is:
https://www.iso.org/standard/71616.html
Page 3 of INTERNATIONAL STANDARD
- ISO/IEC 21778 - Information technology — The JSON data interchange syntax
8 Numbers A number is a sequence of decimal digits with no superfluous leading zero. It may have a preceding minus sign (U+002D). It may have a fractional part prefixed by a decimal point (U+002E). It may have an exponent, prefixed by e (U+0065) or E (U+0045) and optionally + (U+002B) or – (U+002D). The digits are the code points U+0030 through U+0039.
