Function propagateVisitedness

tools/celtest/test_runner.go:1072–1080

propagateVisitedness implements two rules for extending the coverage report: - If a node is visited, all its ancestors are visited. - If a node is visited, and it has only one child, then the child is visited.

(root *cel.Ast, coverageStats map[int64]set, state interpreter.EvalState)

// - If a node is visited, all its ancestors are visited.
// - If a node is visited, and it has only one child, then the child is visited.
func propagateVisitedness(root *cel.Ast, coverageStats map[int64]set, state interpreter.EvalState) {
	if root == nil || coverageStats == nil {
		return
	}
	// Propagate visitedness upwards for ancestors.
	ast.PostOrderVisit(root.NativeRep().Expr(), parentVisitor{coverageStats: coverageStats, evalState: state})
	// Propagate visitedness downwards for single-child nodes.
	ast.PostOrderVisit(root.NativeRep().Expr(), childrenVisitor{coverageStats: coverageStats, evalState: state})
}

// childrenVisitor is a visitor that populates the coverageStats for the child nodes of a given expression.
type childrenVisitor struct {