Don't panic!

data_row_reader.go

@@ -1,5 +1,9 @@
 package pgx
 
+import (
+	"fmt"
+)
+
 // DataRowReader is used by SelectFunc to process incoming rows.
 type DataRowReader struct {
 	mr              *MessageReader
@@ -7,14 +11,14 @@ type DataRowReader struct {
 	currentFieldIdx int
 }
 
-func newDataRowReader(mr *MessageReader, fields []FieldDescription) (r *DataRowReader) {
+func newDataRowReader(mr *MessageReader, fields []FieldDescription) (r *DataRowReader, err error) {
 	r = new(DataRowReader)
 	r.mr = mr
 	r.fields = fields
 
 	fieldCount := int(mr.ReadInt16())
 	if fieldCount != len(fields) {
-		panic("Row description field count and data row field count do not match")
+		return nil, ProtocolError(fmt.Sprintf("Row description field count (%v) and data row field count (%v) do not match", len(fields), fieldCount))
 	}
 
 	return
@@ -34,7 +38,7 @@ func (r *DataRowReader) ReadValue() interface{} {
 			case 1:
 				return vt.DecodeBinary(r.mr, size)
 			default:
-				panic("Unknown format")
+				return ProtocolError(fmt.Sprintf("Unknown field description format code: %v", fieldDescription.FormatCode))
 			}
 		} else {
 			return r.mr.ReadString(size)