6. Setup, main, cleanup and retries

Real tests power a unit before measuring it and must power it off afterwards, whatever happened in between. Sequences have three phases for that.

Create Bench/Fixture.cs and restart the executor:

using Anvil.Step;

/// <summary>The test fixture the board sits in.</summary>
public static class Fixture
{
    /// <summary>Clamps the board and powers it.</summary>
    [Step]
    public static void PowerOn() { }

    /// <summary>Cuts power and releases the board.</summary>
    [Step]
    public static void PowerOff() { }

    /// <summary>Opens the link to the board; the first attempt always times out.</summary>
    [Step]
    public static Outcome Connect(Ctx ctx) =>
        ctx.Attempt == 1
            ? Outcome.Errored("no answer from the board")
            : Outcome.Passed("connected on attempt " + ctx.Attempt);

    /// <summary>Measures the rail while it settles: low on the first attempt.</summary>
    [Step]
    public static double MeasureSettlingRail(Ctx ctx) => ctx.Attempt == 1 ? 4.1 : 4.97;
}

Ctx is optional: declare it as a parameter and the SDK hands you the attempt number, among other things. It is not an input the sequence sends.

Three phases

name: phases

executors:
  - { name: bench, type: grpc, host: 127.0.0.1, port: 9201 }

setup:
  - name: fixture/power_on
    executor: bench

main:
  - name: fixture/measure_settling_rail
    executor: bench
    retries: 3
    limit: { type: range, min: 4.75, max: 5.25 }

  - name: board/check_led
    executor: bench

cleanup:
  - name: fixture/power_off
    executor: bench

$ anvil sequences/phases.yseq 2>/dev/null
=== phases: fail ===
  [pass] fixture/power_on: 
  [fail] fixture/measure_settling_rail: 4.1 fuera de rango [4.75, 5.25]
  [pass] fixture/power_off: 

• setup runs first. If any setup step does not pass, main is skipped entirely.
• main runs next and stops at its first step that does not pass.
• cleanup always runs, whatever happened before. fixture/power_off ran even though the measurement failed. Put everything that makes the bench safe here.

Retries do not re-measure a failed limit

That sequence has retries: 3 on fixture/measure_settling_rail, and the step reads 4.97 V from its second attempt on. Yet the report shows 4.1 and fail.

This is how 0.5.0 behaves (#76): retries repeats a step only while the step itself does not pass. The limit is applied once, after the last attempt. A step that returns a measurement has passed as far as retries are concerned, so it is not called again, and the limit then fails the first value.

Retries are for a step that fails or errors on its own — a link that times out once, for example:

name: retries

executors:
  - { name: bench, type: grpc, host: 127.0.0.1, port: 9201 }

setup:
  - name: fixture/power_on
    executor: bench
  - name: fixture/connect
    executor: bench
    retries: 3

main:
  - name: board/measure_rail
    executor: bench
    limit: { type: range, min: 4.75, max: 5.25 }

cleanup:
  - name: fixture/power_off
    executor: bench

$ anvil sequences/retries.yseq 2>/dev/null
=== retries: pass ===
  [pass] fixture/power_on: 
  [pass] fixture/connect: connected on attempt 2
  [pass] board/measure_rail: 
  [pass] fixture/power_off: 

fixture/connect errored on attempt 1 and passed on attempt 2. retries is the total number of attempts: the default is 1, meaning no retry, and 0 is refused when the file loads.

The report keeps only the last attempt. The “on attempt 2” in the message is there because the step wrote it; Anvil does not record the earlier attempt.

Without the retries, the same link does not come up, and the setup rule shows:

name: setup_fails

executors:
  - { name: bench, type: grpc, host: 127.0.0.1, port: 9201 }

setup:
  - name: fixture/power_on
    executor: bench
  - name: fixture/connect
    executor: bench

main:
  - name: board/measure_rail
    executor: bench
    limit: { type: range, min: 4.75, max: 5.25 }

cleanup:
  - name: fixture/power_off
    executor: bench

$ anvil sequences/setup-fails.yseq 2>/dev/null
=== setup_fails: error ===
  [pass] fixture/power_on: 
  [error] fixture/connect: no answer from the board
  [pass] fixture/power_off: 

The setup errored, main never ran, and cleanup still did.