Correctly diagnose null field

ZewoGraveyard · Nov 3, 2016 · a3dbab5 · a3dbab5
1 parent 05ab2ba
commit a3dbab5
Showing 1 changed file with 8 additions and 2 deletions.
diff --git a/Sources/PostgreSQL/Result.swift b/Sources/PostgreSQL/Result.swift
@@ -81,12 +81,18 @@ public class Result: SQL.ResultProtocol {
     }
 
     public func data(atRow rowIndex: Int, forFieldIndex fieldIndex: Int) -> Buffer? {
+        let rowIndex = Int32(rowIndex)
+        let fieldIndex = Int32(fieldIndex)
 
-        let count = PQgetlength(resultPointer, Int32(rowIndex), Int32(fieldIndex))
-        guard count > 0, let start = PQgetvalue(resultPointer, Int32(rowIndex), Int32(fieldIndex)) else {
+        guard PQgetisnull(resultPointer, rowIndex, fieldIndex) == 0 else {
             return nil
         }
 
+        let count = PQgetlength(resultPointer, rowIndex, fieldIndex)
+        guard count > 0, let start = PQgetvalue(resultPointer, rowIndex, fieldIndex) else {
+            return Buffer()
+        }
+
         return start.withMemoryRebound(to: UInt8.self, capacity: Int(count)) { start in
             return Buffer(Array(UnsafeBufferPointer(start: start, count: Int(count))))
         }