Function compactBindingContexts

pkg/task/queue/task_queue.go:573–622

compactBindingContexts mimics the logic from shell-operator's CombineBindingContextForHook. It removes intermediate states for the same group, keeping only the most recent one.

(combinedContext []bindingcontext.BindingContext)

// compactBindingContexts mimics the logic from shell-operator's CombineBindingContextForHook.
// It removes intermediate states for the same group, keeping only the most recent one.
func compactBindingContexts(combinedContext []bindingcontext.BindingContext) []bindingcontext.BindingContext {
	if len(combinedContext) < 2 {
		return combinedContext
	}

	// Count ungrouped contexts and estimate result size
	ungroupedCount := 0
	groupCount := 0
	for _, bc := range combinedContext {
		if bc.Metadata.Group == "" {
			ungroupedCount++
		} else {
			groupCount++
		}
	}

	// If no grouped contexts, return as is
	if groupCount == 0 {
		return combinedContext
	}

	// Use a single pass approach with a map to track the last occurrence of each group
	lastIndexForGroup := make(map[string]int, groupCount)
	ungroupedIndices := make([]int, 0, ungroupedCount)

	for i, bc := range combinedContext {
		group := bc.Metadata.Group
		if group == "" {
			ungroupedIndices = append(ungroupedIndices, i)
		} else {
			lastIndexForGroup[group] = i
		}
	}

	// Pre-allocate result slice with exact capacity
	resultSize := len(ungroupedIndices) + len(lastIndexForGroup)
	result := make([]bindingcontext.BindingContext, 0, resultSize)

	// Add ungrouped contexts first (preserving their order)
	for _, idx := range ungroupedIndices {
		result = append(result, combinedContext[idx])
	}

	// Add the last occurrence of each group
	for _, idx := range lastIndexForGroup {
		result = append(result, combinedContext[idx])
	}

	return result
}

// RemoveLast deletes a tail element, so tail is moved.
func (q *TaskQueue) RemoveLast() task.Task {