Fix decoding row with same type values

Row decoding was reusing and returning connection owned values for
decoding. Instead allocate new value each time.

fixes #313

pgtype/record.go

@@ -2,6 +2,7 @@ package pgtype
 
 import (
 	"encoding/binary"
+	"reflect"
 
 	"github.com/pkg/errors"
 )
@@ -111,6 +112,9 @@ func (dst *Record) DecodeBinary(ci *ConnInfo, src []byte) error {
 			rp += fieldLen
 		}
 
+		// Duplicate struct to scan into
+		binaryDecoder = reflect.New(reflect.ValueOf(binaryDecoder).Elem().Type()).Interface().(BinaryDecoder)
+
 		if err := binaryDecoder.DecodeBinary(ci, fieldBytes); err != nil {
 			return err
 		}

pgtype/record_test.go

@@ -35,6 +35,16 @@ func TestRecordTranscode(t *testing.T) {
 				Status: pgtype.Present,
 			},
 		},
+		{
+			sql: `select row(100.0::float4, 1.09::float4)`,
+			expected: pgtype.Record{
+				Fields: []pgtype.Value{
+					&pgtype.Float4{Float: 100, Status: pgtype.Present},
+					&pgtype.Float4{Float: 1.09, Status: pgtype.Present},
+				},
+				Status: pgtype.Present,
+			},
+		},
 		{
 			sql: `select row('foo'::text, array[1, 2, null, 4]::int4[], 42::int4)`,
 			expected: pgtype.Record{
@@ -87,7 +97,7 @@ func TestRecordTranscode(t *testing.T) {
 		}
 
 		if !reflect.DeepEqual(tt.expected, result) {
-			t.Errorf("%d: expected %v, got %v", i, tt.expected, result)
+			t.Errorf("%d: expected %#v, got %#v", i, tt.expected, result)
 		}
 	}
 }

values_test.go

@@ -931,6 +931,13 @@ func TestRowDecode(t *testing.T) {
 				time.Date(2015, 1, 1, 8, 12, 42, 0, time.UTC).Local(),
 			},
 		},
+		{
+			"select row(100.0::float, 1.09::float)",
+			[]interface{}{
+				float64(100),
+				float64(1.09),
+			},
+		},
 	}
 
 	for i, tt := range tests {