Function exprLinesFromPolicy

policy/compiler_test.go:585–619

exprLinesFromPolicy returns a set of line numbers within a policy where expressions (variables, conditions, etc.) are defined.

(policy *Policy)

// exprLinesFromPolicy returns a set of line numbers within a policy where expressions (variables,
// conditions, etc.) are defined.
func exprLinesFromPolicy(policy *Policy) map[int]bool {
	lines := make(map[int]bool)
	addExpectedLines := func(vs ValueString) {
		if offset, found := policy.SourceInfo().GetOffsetRange(vs.ID); found {
			startLoc, foundStart := policy.Source().OffsetLocation(offset.Start)
			// Multiline strings can span multiple lines, but the SourceInfo will only contain the start
			// position of the expression. So just skip the check if the expression contains a multiline
			// string literal.
			hasMultiline := strings.Contains(vs.Value, "'''") || strings.Contains(vs.Value, "\"\"\"")
			if foundStart && !hasMultiline {
				numLines := strings.Count(vs.Value, "\n")
				for i := 0; i <= numLines; i++ {
					lines[startLoc.Line()+i] = true
				}
			}
		}
	}
	var traverseRule func(r *Rule)
	traverseRule = func(r *Rule) {
		for _, v := range r.Variables() {
			addExpectedLines(v.Expression())
		}
		for _, m := range r.Matches() {
			addExpectedLines(m.Condition())
			if m.HasOutput() {
				addExpectedLines(m.Output())
			}
			if m.HasRule() {
				traverseRule(m.Rule())
			}
		}
	}
	traverseRule(policy.Rule())
	return lines
}