Handle Scanning null into core types

Return error instead of panic.

query_test.go

@@ -408,6 +408,15 @@ func TestQueryRowCoreTypes(t *testing.T) {
 			}
 
 			ensureConnValid(t, conn)
+
+			// Check that Scan errors when a core type is null
+			err = conn.QueryRow(sql, nil).Scan(tt.scanArgs...)
+			if err == nil {
+				t.Errorf("%d. Expected null to cause error, but it didn't (sql -> %v)", i, sql)
+			}
+			if err != nil && !strings.Contains(err.Error(), "Cannot decode null") {
+				t.Errorf(`%d. Expected null to cause error "Cannot decode null..." but it was %v (sql -> %v)`, i, err, sql)
+			}
 		}
 	}
 }

values.go

@@ -527,6 +527,11 @@ func sanitizeArg(arg interface{}) (string, error) {
 }
 
 func decodeBool(vr *ValueReader) bool {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into bool"))
+		return false
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -571,6 +576,11 @@ func encodeBool(w *WriteBuf, value interface{}) error {
 }
 
 func decodeInt8(vr *ValueReader) int64 {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into int64"))
+		return 0
+	}
+
 	if vr.Type().DataType != Int8Oid {
 		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int8Oid, vr.Type().DataType)))
 		return 0
@@ -632,6 +642,11 @@ func encodeInt8(w *WriteBuf, value interface{}) error {
 }
 
 func decodeInt2(vr *ValueReader) int16 {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into int16"))
+		return 0
+	}
+
 	if vr.Type().DataType != Int2Oid {
 		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int2Oid, vr.Type().DataType)))
 		return 0
@@ -708,6 +723,11 @@ func encodeInt2(w *WriteBuf, value interface{}) error {
 }
 
 func decodeInt4(vr *ValueReader) int32 {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into int32"))
+		return 0
+	}
+
 	if vr.Type().DataType != Int4Oid {
 		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int4Oid, vr.Type().DataType)))
 		return 0
@@ -777,6 +797,11 @@ func encodeInt4(w *WriteBuf, value interface{}) error {
 }
 
 func decodeFloat4(vr *ValueReader) float32 {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into float32"))
+		return 0
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -824,6 +849,11 @@ func encodeFloat4(w *WriteBuf, value interface{}) error {
 }
 
 func decodeFloat8(vr *ValueReader) float64 {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into float64"))
+		return 0
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -868,6 +898,11 @@ func encodeFloat8(w *WriteBuf, value interface{}) error {
 }
 
 func decodeText(vr *ValueReader) string {
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into string"))
+		return ""
+	}
+
 	return vr.ReadString(vr.Len())
 }
 
@@ -884,6 +919,10 @@ func encodeText(w *WriteBuf, value interface{}) error {
 }
 
 func decodeBytea(vr *ValueReader) []byte {
+	if vr.Len() == -1 {
+		return nil
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -916,6 +955,11 @@ func encodeBytea(w *WriteBuf, value interface{}) error {
 func decodeDate(vr *ValueReader) time.Time {
 	var zeroTime time.Time
 
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into time.Time"))
+		return zeroTime
+	}
+
 	if vr.Type().DataType != DateOid {
 		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", DateOid, vr.Type().DataType)))
 		return zeroTime
@@ -957,6 +1001,11 @@ const microsecFromUnixEpochToY2K = 946684800 * 1000000
 func decodeTimestampTz(vr *ValueReader) time.Time {
 	var zeroTime time.Time
 
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into time.Time"))
+		return zeroTime
+	}
+
 	if vr.Type().DataType != TimestampTzOid {
 		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", TimestampTzOid, vr.Type().DataType)))
 		return zeroTime
@@ -1002,6 +1051,11 @@ func encodeTimestampTz(w *WriteBuf, value interface{}) error {
 func decodeTimestamp(vr *ValueReader) time.Time {
 	var zeroTime time.Time
 
+	if vr.Len() == -1 {
+		vr.Fatal(ProtocolError("Cannot decode null into timestamp"))
+		return zeroTime
+	}
+
 	if vr.Type().DataType != TimestampOid {
 		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", TimestampOid, vr.Type().DataType)))
 		return zeroTime