Run the same test with different data in Jest

When you write a test in Jest and you want to run it with different data, you can use the test.each function. The function accepts a data table, which is an array of arrays with the arguments that are passed to the actual test function.

const table = [
  ["one", 1],
  ["two", 2],
  ["three", 3],
];

test.each(table)("converts %s to %d", (str, expected) => {
  // Will be called 3 times with "one", "two", "three"
  const result = convertToNumber(str);
  expect(result).toBe(expected);
});

The title of the test can inject parameters with printf formatting (like %s for a string and %d for a number).

Read more about this in the Jest documentation.