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jestjsstring-comparisonts-jest

Jest expect.stringMatching() SyntaxError: Invalid regular expression

We have: A function that returns random values (In our case, crypto -> aes)

What do we want to do? Compare that this string is not equal to the past

We mean that the object in which the string is located is large enough, so we compare the string inside the object, and not separately

How do we compare?

const oldCiper = "oldRandom+String-/FromAny==Characters";

// Pay attention to the plus sign at the beginning of a new line
const newCiper = "+newRandomString-\From/Any==Charac+ters";

// We will get an error here 
// SyntaxError: Invalid regular expression...
expect({cipher: oldCiper }).toEqual({cipher: expect.not.stringMatching(newCiper)})

Full Error: SyntaxError: Invalid regular expression: /+newRandomString-\From/Any==Charac+ters/: Nothing to repeat

Solution

  • Solution

    Use stringContaining instead of stringMatching

    const oldCiper = "oldRandom+String-/FromAny==Characters";

const newCiper = "+newRandomString-\From/Any==Charac+ters";

expect({cipher: oldCiper }).toEqual({cipher: expect.not.stringContaining(newCiper)})

    The first character for an error can be not only a plus, but also "W", "L", etc.