toEqual does not treat non-enumerable properties equally #6392
Description
🐛 Bug Report
I discovered some inconsistent behavior in the toEqual matcher in Jest; when comparing to objects, it ignores non-enumerable properties, but only if they are not symbols. This leads to quite inconsistent behavior:
This test passes:
const actual1 = {
x: 3
}
Object.defineProperty(actual1, "test", {
enumerable: false,
value: 5
})
expect(actual1).toEqual({ x: 3 })But this one doesn't:
const actual2 = {
x: 3
}
const mySymbol = Symbol("test")
Object.defineProperty(actual2, mySymbol, {
enumerable: false,
value: 5
})
expect(actual2).toEqual({ x: 3 })Where one would expect both to behave the same.
The cause of the issue can be found here. To find the string properties the for..in loop is used which ignores non-enumerable properties, but for the symbolic properties getOwnPropertySymbols is used, which will include non-enumerable properties.
To Reproduce
See link below
Expected behavior
Non-enumerable symbolic properties should be treated the same as non-enumerable non-symbolic properties when running toEqual. Either both should be included, or excluded. Given that symbolic properties are lot more exotic, I think the behavior of string properties should be followed and non-enumerable symbolic properties should be excluded from deep equality.
I am willing to file a PR myself
Link to repl or repo (highly encouraged)
https://repl.it/@mweststrate/IckyMeanProgrammers
Run npx envinfo --preset jest
Paste the results here:
System:
OS: Linux 4.15 Ubuntu 18.04 LTS (Bionic Beaver)
CPU: x64 Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz
Binaries:
Node: 9.3.0 - ~/.nvm/versions/node/v9.3.0/bin/node
Yarn: 1.6.0 - /usr/bin/yarn
npm: 5.5.1 - ~/.nvm/versions/node/v9.3.0/bin/npm
npmPackages:
@types/jest: ^21.1.9 => 21.1.10
jest: ^22.0.4 => 22.4.4