Function TestRegexCosts

ext/regex_test.go:277–417

(t *testing.T)

}

func TestRegexCosts(t *testing.T) {
	tests := []struct {
		expr          string
		vars          []cel.EnvOption
		in            map[string]any
		hints         map[string]uint64
		estimatedCost checker.CostEstimate
		actualCost    uint64
	}{
		{
			expr:          `regex.extract('hello world', 'hello (.*)') == optional.of('world')`,
			estimatedCost: checker.CostEstimate{Min: 8, Max: 20},
			actualCost:    8,
		},
		// - Estimated Cost (Min: 5): Derived from fixed costs of scanning 10-char
		//   target string and compiling 2-char regex. Since the inputs are constant,
		//   the Min estimate is very accurate.
		// - Actual Cost (5): Observed cost is the sum of a base call cost (~1), the
		//   search cost, and the allocation cost for the 2-char result string '22'.
		//   It aligns perfectly with the minimum estimate.
		{
			expr:          "regex.extract('4122345432', '22').orValue('777') == '22'",
			estimatedCost: checker.CostEstimate{Min: 4, Max: 14},
			actualCost:    4,
		},
		// .or() condition introduces runtime uncertainty, and since the cost estimator
		// can't know which branch the code will take, it must prepare for the most
		// expensive possible outcome resulting in an estimate.Max of ~ math.MaxUint64.
		{
			expr:          "regex.extract('4122345432', '22').or(optional.of('777')) == optional.of('22')",
			estimatedCost: checker.CostEstimate{Min: 6, Max: 1844674407370955279},
			actualCost:    5,
		},
		{
			expr:          "regex.extract('hello world', 'goodbye (.*)') == optional.none()",
			estimatedCost: checker.CostEstimate{Min: 10, Max: 22},
			actualCost:    8,
		},
		{
			expr:          "regex.extractAll('id:123, id:456', 'assa') == []",
			estimatedCost: checker.CostEstimate{Min: 24, Max: 38},
			actualCost:    23,
		},
		// - Estimated Cost (Min: 25): Cost to scan the 14-char target and compile
		//   5-char regex, plus a worst-case allocation cost for the result list's
		//   contents, which is estimated as the full 14-char size of the target.
		// - Actual Cost (28): Observed cost includes the search cost plus the actual
		//   allocation cost, which is the base list creation cost plus the cost of
		//   allocating the two result strings, totaling 12 chars of content.
		{
			expr:          `regex.extractAll('id:123, id:456', r'id:\d+') == ['id:123', 'id:456']`,
			estimatedCost: checker.CostEstimate{Min: 25, Max: 39},
			actualCost:    27,
		},
		{
			expr:          `regex.extractAll('a b c', r'(\S*)\s*') == ['a', 'b', 'c']`,
			estimatedCost: checker.CostEstimate{Min: 24, Max: 29},
			actualCost:    27,