flag.value_untested: A flag is read where no test that reaches the read gives it one of its values

A flag is read where no test that reaches the read gives it one of its values.

Area 16, Built-in services; not declinable; the next step is usually the agent's.

Why Jadpo refuses it

A flag ships code switched off, then turns it on while the app runs, with no deploy in between. Each value takes a different way through the code, so a branch no test ran is first run by your users, the moment someone changes the flag. Jadpo knows every read of every flag and what each test reaches, so it checks that the tests reaching each read give the flag every value it can have, before anyone can switch it.

A test gives a flag the value its flags: names, or else its default:. This can't be declined: a flag is only safe to change when each of its branches has been tested.

What it looks like

A test of the default only:

example

type CheckoutSteps = Int {    min: 1    max: 3}flags {    new_checkout: Bool {        default: false        owner: "payments"        expires: "2099-01-31"    }}action checkout_steps() -> CheckoutSteps {    if (flags.new_checkout) {        return 1    }    return 3}test "the three-step form is shown by default" {    assert checkout_steps() == 3}

jadpo checkcheck failed: 1 error, 1 file

error No test that reaches flags.new_checkout gives it true

--> main.jadpo:15:9

   |15 |     if (flags.new_checkout) {   |         ^^^^^^^^^^^^^^^^^^ not tested with every value

reason: Each read of a flag is tested with every value it can have, so each branch is known to work before the flag is switched. The tests that reach it give it only false. A test that doesn't name the flag in its flags: gives it the default:, false.
next: Add a test that reaches this read with flags: { new_checkout: true } (agent)
rule: flag.value_untested
help: https://jadpo.dev/docs/errors/flag.value_untested

(agent) at the end of the next: line means your coding agent can make the fix itself.

How to fix it

If a value has no test, add one that reaches the read with that value in its flags::

example

test "the new checkout takes one page" {    flags: {        new_checkout: true    }    assert checkout_steps() == 1}

Both branches are now tested, so the flag can be switched either way.

Why Jadpo refuses it

What it looks like

How to fix it

Related