# gs-timing

[GS Open Source](https://garrity.co/oss.html) |
[License (MIT)](./LICENSE)

Timing library for Cats Effect and Scala 3.

- [Usage](#usage)
- [Donate](#donate)

## Usage

### Dependency

This artifact is available in the Garrity Software Maven repository.

```scala
externalResolvers +=
  "Garrity Software Releases" at "https://maven.garrity.co/gs"

val Gstiming: ModuleID =
  "gs" %% "gs-timing-v0" % "$VERSION"
```

### System Time

```scala
import gs.timing.v0.*
import cats.effect.IO
import cats.effect.unsafe.IORuntime

given IORuntime = IORuntime.global

val timing = new Timing(MonotonicProvider.system[IO])

val nanoTime: Long = timing.monotonic().unsafeRunSync()
```

### Elapsed Time

```
import gs.timing.v0.*
import cats.effect.IO
import cats.effect.unsafe.IORuntime
import scala.concurrent.duration._

given IORuntime = IORuntime.global

val timing = new Timing(MonotonicProvider.system[IO])

val program: IO[(ElapsedTime, ElapsedTime)] =
  for
    timer    <- timing.start()
    _        <- IO.sleep(1.seconds)
    elapsed1 <- timer.checkpoint()
    _        <- IO.sleep(1.seconds)
    elapsed2 <- timer.checkpoint()
  yield
    (elapsed1, elapsed2)

val (e1, e2) = program.unsafeRunSync()
assert(e1.start == e2.start)
assert(e1.end != e2.end)
println(e1.duration)
println(e1.toNanoseconds())
println(e1.toMilliseconds())
println(e1.toSeconds())
```

### Testing

For example, using munit and a simple helper for running IO-based tests:

```
iotest("should retrieve monotonic time") {
  for
    (provider, timing) <- Timing.manual[IO]
    t1                 <- timing.monotonic()
    t2                 <- timing.monotonic()
    _                  <- provider.tick()
    t3                 <- timing.monotonic()
    _                  <- provider.tick()
    t4                 <- timing.monotonic()
    _                  <- provider.reset()
    t5                 <- timing.monotonic()
  yield
    assertEquals(t1, 0L)
    assertEquals(t2, 0L)
    assertEquals(t3, 1L)
    assertEquals(t4, 2L)
    assertEquals(t5, 0L)
}
```

## Donate

Enjoy this project or want to help me achieve my [goals](https://garrity.co)?
Consider [Donating to Pat on Ko-fi](https://ko-fi.com/gspfm).