# `Accrue.Clock`
[🔗](https://github.com/szTheory/accrue/blob/accrue-v0.3.0/lib/accrue/clock.ex#L1)

Canonical time source for Accrue (D3-86).

All code inside Accrue that needs "now" MUST call `Accrue.Clock.utc_now/0`
instead of `DateTime.utc_now/0`. In the test environment (`:accrue, :env`
set to `:test`) this delegates to `Accrue.Processor.Fake.now/0`, which is
backed by the Fake processor's in-memory test clock. In any other
environment it delegates to the BEAM's `DateTime.utc_now/0`.

This indirection is what makes the Fake Processor the primary test
surface (TEST-01): time-sensitive billing logic (trial ends, dunning,
expiring-card notices) can be exercised deterministically by advancing
the Fake clock rather than by sleeping or by stubbing `DateTime`.

## Why application env, not compile env

The `:env` flag is read at runtime via `Application.get_env/3` so host
apps can flip it in tests without recompiling Accrue. Production never
reaches the Fake branch because the default is `:prod` and host apps
never set `:accrue, :env` to anything but `:test`.

# `utc_now`

```elixir
@spec utc_now() :: DateTime.t()
```

---

*Consult [api-reference.md](api-reference.md) for complete listing*