When to use expect.stringContaining instead of toContain for substring matching in Jest

user_5747510 0
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What's the use case to use stringContaining instead of just using toContain for substring matching with Jest?

it("tests with stringContaining", () => {
  expect("testerama").toEqual(expect.stringContaining("test"))
})
it("tests with toContain", () => {
  expect("testerama").toContain("test")
})

As far as I can see the behaviour is similar apart from that if the string is null or undefined the stringContaining error message is a bit clearer.

Expected: StringContaining "test"
Received: null

as opposed to

Matcher error: received value must not be null nor undefined
Received has value: null

It hardly seems worth it for the less terse code. Am I missing something?

jestjs
1 Answers

The only real difference is that the expect.stringContaining method is maintained by the community, whereas expect.toContain is part of the official Jest API.

user_17183120
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