dialect/sql: support mapping non-lowercased tags

dialect/sql/scan.go

@@ -213,10 +213,15 @@ func scanStruct(typ reflect.Type, columns []string) (*rowScan, error) {
 		names[columnName(f)] = []int{i}
 	}
 	for _, c := range columns {
-		// Normalize columns if necessary, for example: COUNT(*) => count.
-		name := strings.ToLower(strings.Split(c, "(")[0])
-		idx, ok := names[name]
-		if !ok {
+		var idx []int
+		// Normalize columns if necessary,
+		// for example: COUNT(*) => count.
+		switch name := strings.Split(c, "(")[0]; {
+		case names[name] != nil:
+			idx = names[name]
+		case names[strings.ToLower(name)] != nil:
+			idx = names[strings.ToLower(name)]
+		default:
 			return nil, fmt.Errorf("sql/scan: missing struct field for column: %s (%s)", c, name)
 		}
 		idxs = append(idxs, idx)

dialect/sql/scan_test.go

@@ -140,6 +140,17 @@ func TestScanSlice(t *testing.T) {
 	require.Empty(t, pp)
 }
 
+func TestScanSlice_CamelTags(t *testing.T) {
+	mock := sqlmock.NewRows([]string{"nickName"}).
+		AddRow("foo").
+		AddRow("bar")
+	var v []*struct {
+		NickName string `json:"nickName"`
+	}
+	require.NoError(t, ScanSlice(toRows(mock), &v))
+	require.Equal(t, "foo", v[0].NickName)
+}
+
 func TestScanJSON(t *testing.T) {
 	mock := sqlmock.NewRows([]string{"v", "p"}).
 		AddRow([]byte(`{"i": 1, "s":"a8m"}`), []byte(`{"i": 1, "s":"a8m"}`)).