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# x <= snapshot()

## General

A snapshot can be compared against any value with `<=` or `>=`. This can be used to create an upper/lower bound for some result. The snapshot value can be trimmed to the lowest/largest valid value.

Example:

original code--inline-snapshot=create optimized code --inline-snapshot=trim

    from inline_snapshot import snapshot

    def gcd(x, y):
        iterations = 0
        if x > y:
            small = y
        else:
            small = x
        for i in range(1, small + 1):
            iterations += 1
            if (x % i == 0) and (y % i == 0):
                gcd = i

        return gcd, iterations

    def test_gcd():
        result, iterations = gcd(12, 18)

        assert result == snapshot()
        assert iterations <= snapshot()

    from inline_snapshot import snapshot

    def gcd(x, y):
        iterations = 0
        if x > y:
            small = y
        else:
            small = x
        for i in range(1, small + 1):
            iterations += 1
            if (x % i == 0) and (y % i == 0):
                gcd = i

        return gcd, iterations

    def test_gcd():
        result, iterations = gcd(12, 18)

        assert result == snapshot(6)
        assert iterations <= snapshot(12)

    from inline_snapshot import snapshot

    def gcd(x, y):
        # use Euclidean Algorithm
        iterations = 0
        while y:
            iterations += 1
            x, y = y, x % y
        return abs(x), iterations

    def test_gcd():
        result, iterations = gcd(12, 18)

        assert result == snapshot(6)
        assert iterations <= snapshot(12)

    from inline_snapshot import snapshot

    def gcd(x, y):
        # use Euclidean Algorithm
        iterations = 0
        while y:
            iterations += 1
            x, y = y, x % y
        return abs(x), iterations

    def test_gcd():
        result, iterations = gcd(12, 18)

        assert result == snapshot(6)
        assert iterations <= snapshot(3)

Warning

This should not be used to check for any flaky values like the runtime of some code, because it will randomly break your tests.

The same snapshot value can also be used in multiple assertions.

original code--inline-snapshot=create

    from inline_snapshot import snapshot

    def test_something():
        value = snapshot()

        assert 5 <= value
        assert 6 <= value

    from inline_snapshot import snapshot

    def test_something():
        value = snapshot(6)

        assert 5 <= value
        assert 6 <= value

## pytest options

It interacts with the following `--inline-snapshot` flags:

- `create` create a new value if the snapshot value is undefined.
- `fix` record the new value and store it in the source code if it contradicts the comparison.
- `trim` record the new value and store it in the source code if it is stricter than the old one.