func()

in workflow.go [322:361]

• 35 lines of code
• 12 McCabe index (conditional complexity)

func (w *Workflow) preflight() error {
	// assert all dependency would not form a cycle
	// start scanning, mark Step as Scanned only when its all dependencies are Scanned
	for {
		hasNewScanned := false // whether a new Step being marked as Scanned this turn
		for step, state := range w.steps {
			if state.GetStatus() == scanned {
				continue
			}
			if isAllUpstreamScanned(w.UpstreamOf(step)) {
				hasNewScanned = true
				state.SetStatus(scanned)
			}
		}
		if !hasNewScanned { // break when no new Step being Scanned
			break
		}
	}
	// check whether still have Steps not Scanned,
	// not Scanned Steps are in a cycle.
	stepsInCycle := make(ErrCycleDependency)
	for step, state := range w.steps {
		if state.GetStatus() == scanned {
			continue
		}
		for up, statusErr := range w.UpstreamOf(step) {
			if statusErr.Status != scanned {
				stepsInCycle[step] = append(stepsInCycle[step], up)
			}
		}
	}
	if len(stepsInCycle) > 0 {
		return stepsInCycle
	}
	// reset all Steps' status to Pending
	for _, step := range w.steps {
		step.SetStatus(Pending)
	}
	return nil
}