Function parseArguments

dql/parser.go:1360–1458

parseArguments parses the arguments part of the DQL query root.

(it *lex.ItemIterator, gq *GraphQuery)

// parseArguments parses the arguments part of the DQL query root.
func parseArguments(it *lex.ItemIterator, gq *GraphQuery) (result []pair, rerr error) {
	expectArg := true
	orderCount := 0
loop:
	for it.Next() {
		var p pair
		// Get key.
		item := it.Item()
		switch item.Typ {
		case itemName:
			if !expectArg {
				return result, item.Errorf("Expecting a comma. But got: %v", item.Val)
			}
			p.Key = collectName(it, item.Val)
			if isSortkey(p.Key) {
				orderCount++
			}
			expectArg = false
		case itemRightRound:
			if expectArg {
				return result, item.Errorf("Expected argument but got ')'.")
			}
			break loop
		case itemComma:
			if expectArg {
				return result, item.Errorf("Expected Argument but got comma.")
			}
			expectArg = true
			continue
		default:
			return result, item.Errorf("Expecting argument name. Got: %v", item)
		}

		it.Next()
		item = it.Item()
		if item.Typ != itemColon {
			return result, item.Errorf("Expecting a colon. Got: %v in %v", item, gq.Attr)
		}

		// Get value.
		it.Next()
		item = it.Item()
		var val string
		if item.Val == valueFunc {
			count, err := parseVarList(it, gq)
			if err != nil {
				return result, err
			}
			if count != 1 {
				return result, item.Errorf("Only one variable expected. Got %d", count)
			}
			gq.NeedsVar[len(gq.NeedsVar)-1].Typ = ValueVar
			p.Val = gq.NeedsVar[len(gq.NeedsVar)-1].Name
			result = append(result, p)
			if isSortkey(p.Key) && orderCount > 1 {
				return result, item.Errorf("Multiple sorting only allowed by predicates. Got: %+v",
					p.Val)
			}