product: maestro audience: test-developer authority: normative

Runtime Control Fields

enabled — static disable

false → step IS immediately SKIPPED without executing.

- name: "Legacy step"
  type: mock
  enabled: false

precondition — conditional execution

A DynamicExpresso boolean expression evaluated at runtime. false → SKIPPED. Exception during evaluation → ABORTED.

- name: "Calibrate"
  type: mock
  precondition: "runCalibration == true"

Supported syntax:

• variable == true / variable == false
• temperature > 25
• a == true && b < 3
• skipCal == true || forceRun == true

cfg.*, exec.*, and mes.* MUST NOT be used in precondition: expressions. These namespaces use dot notation which DynamicExpresso interprets as C# member access. To branch on a cfg.* value, read it into a bare variable in a preceding step.

force — verdict override

- name: "Noisy measurement"
  type: mock
  force: "pass"

retry — retry on failure

- name: "Flaky instrument read"
  runner: dotnet
  runner_type: net10.0
  assembly: "Tests.dll"
  class: "Tests.Instruments"
  method: "ReadDMM"
  retry:
    count: 3        # 3 retries → 4 total attempts
    delay_ms: 500

repeat — condition-based loop

Two built-in variables are set before each iteration:

max_iterations IS required as a safety cap.

- name: "Sweep 5 points"
  runner: python
  runner_type: python3.11
  module: "sweep"
  function: "measure_point"
  parameters:
    step: "{{__iteration__}}"
  repeat:
    condition: "__iteration__ < 4"   # iterations 0–4 = 5 total
    max_iterations: 10

Looping a sub-sequence

repeat works on type: sequence steps. __iteration__ and __cycle__ are available inside the child YAML through the shared variable scope. Use __cycle__ to produce readable measurement names like VOUT_CYCLE1, VOUT_CYCLE2.

Every sub-sequence file MUST have a test: root element with name: and version:. The format is identical to a top-level test file; the engine ignores setup: and teardown: blocks inside sub-sequences. Only the steps: list is executed inline.

This is intentional — see Standalone / Composite Test Pattern for how to use this behaviour to write sub-sequences that work both as independent tests and as reusable modules in a full suite.

# poe.yaml — top-level test
steps:
  - name: "Power cycle"
    type: sequence
    sequence: "tests/poe-cycle.yaml"
    repeat:
      condition: "__iteration__ < 2"   # 2 cycles
      max_iterations: 5
    post_execution_action: terminate-on-fail

# tests/poe-cycle.yaml — the reusable sub-sequence
test:
  name: "PoE power cycle (sub-sequence)"
  version: "1.0.0"
  steps:
    - name: "[Cycle {{__cycle__}}] Enable detection"
      runner: dotnet
      runner_type: net10.0
      assembly: "regressiontests.dll"
      class: "regressiontests.Poe"
      method: "EnableDetectionAndClassification"
      post_execution_action: terminate-on-fail

    - name: "[Cycle {{__cycle__}}] Read registers"
      runner: dotnet
      runner_type: net10.0
      assembly: "regressiontests.dll"
      class: "regressiontests.Poe"
      method: "DumpRegisters"
      outputs:
        opmode: "{{opmode_ch1}}"
        vin:    "{{vin}}"
      measurements:
        - { name: "OPMODE_CYCLE{{__cycle__}}",  type: string, value: "{{opmode_ch1}}" }
        - { name: "VIN_CYCLE{{__cycle__}}",     value: "{{vin}}", unit: "V", operator: log }

timeout_ms — per-attempt wall-clock timeout

Hardware steps MUST always carry timeout_ms. An instrument that stops responding will otherwise block the runner indefinitely.

- name: "Flash firmware"
  runner: dotnet
  runner_type: net10.0
  assembly: "FlashTools.dll"
  class: "FlashTools.Programmer"
  method: "Flash"
  timeout_ms: 30000

run_on_abort — guaranteed cleanup

true → the step IS executed even when the test is aborting. MUST be set on all power-down, disconnect, and instrument-release steps.

- name: "Power down (always runs)"
  runner: dotnet
  runner_type: net10.0
  assembly: "Tests.dll"
  class: "Tests.Cleanup"
  method: "PowerDown"
  run_on_abort: true

post_execution_action

MUST be set to terminate-on-fail on all power-on, connect, and init steps.

requires — shared-instrument locking (parallel stations)

A list of named shared resources the step needs exclusive access to. When the station runs more than one test at a time (MaxParallelExecutions > 1), concurrent tests share the bench instruments; requires: tells the engine to serialise access to each named resource. The whole set is acquired atomically before the step runs and released after.

- name: "Measure 3V3 Rail"
  runner: dotnet
  runner_type: net10.0
  assembly: "PowerTests.dll"
  class: "MyTests.PowerTests"
  method: "MeasureVoltage"
  requires: [dmm, mux]        # exclusive DMM + mux for the duration of this step
  measurement:
    name: "RAIL_3V3"
    value: "{{result}}"
    low_limit: 3.135
    high_limit: 3.465
    unit: "V"

Rules:

• Names are free-form — use one consistent name per physical instrument across the whole station (e.g. dmm, psu, mux, scope).
• The set is acquired in a fixed order, so declaring requires: can never deadlock.
• On a single-execution station (MaxParallelExecutions = 1, the default) this has no effect — but it is always safe to declare, and makes the package correct on a parallel station.
• Any step that touches a shared instrument MUST declare it. Omitting requires: is the common cause of corrupted measurements when two tests run at once.