Method buildMacroCallArg

parser/helper.go:193–223

buildMacroCallArg iterates the expression and returns a new expression where all macros have been replaced by their IDs in MacroCalls

(expr ast.Expr)

// buildMacroCallArg iterates the expression and returns a new expression
// where all macros have been replaced by their IDs in MacroCalls
func (p *parserHelper) buildMacroCallArg(expr ast.Expr) ast.Expr {
	if _, found := p.sourceInfo.GetMacroCall(expr.ID()); found {
		return p.exprFactory.NewUnspecifiedExpr(expr.ID())
	}

	switch expr.Kind() {
	case ast.CallKind:
		// Iterate the AST from `expr` recursively looking for macros. Because we are at most
		// starting from the top level macro, this recursion is bounded by the size of the AST. This
		// means that the depth check on the AST during parsing will catch recursion overflows
		// before we get to here.
		call := expr.AsCall()
		macroArgs := make([]ast.Expr, len(call.Args()))
		for index, arg := range call.Args() {
			macroArgs[index] = p.buildMacroCallArg(arg)
		}
		if !call.IsMemberFunction() {
			return p.exprFactory.NewCall(expr.ID(), call.FunctionName(), macroArgs...)
		}
		macroTarget := p.buildMacroCallArg(call.Target())
		return p.exprFactory.NewMemberCall(expr.ID(), call.FunctionName(), macroTarget, macroArgs...)
	case ast.ListKind:
		list := expr.AsList()
		macroListArgs := make([]ast.Expr, list.Size())
		for i, elem := range list.Elements() {
			macroListArgs[i] = p.buildMacroCallArg(elem)
		}
		return p.exprFactory.NewList(expr.ID(), macroListArgs, list.OptionalIndices())
	}
	return expr
}

// addMacroCall adds the macro the the MacroCalls map in source info. If a macro has args/subargs/target
// that are macros, their ID will be stored instead for later self-lookups.