Add special type for scanning of unused columns (V1) (#132) (#134)

* add noOpScanType

* remove Value method

* add test for scanning of unknown enum

* fix tests

* update db version

* fix codecov

* use token in codecov

---------

Co-authored-by: br3w0r <daniildirun123@gmail.com>

Author: georgysavva

.github/workflows/test.yml

@@ -27,8 +27,8 @@ jobs:
     steps:
       - name: Download CockroachDB Binary
         run: |
-          wget -qO- https://binaries.cockroachdb.com/cockroach-v20.1.3.linux-amd64.tgz | tar  xvz
-          sudo cp -i cockroach-v20.1.3.linux-amd64/cockroach /usr/local/bin/
+          wget -qO- https://binaries.cockroachdb.com/cockroach-v23.2.3.linux-amd64.tgz | tar  xvz
+          sudo cp -i cockroach-v23.2.3.linux-amd64/cockroach /usr/local/bin/
 
       - name: Install Go
         uses: actions/setup-go@v3
@@ -56,12 +56,12 @@ jobs:
         run: go test --tags with_mssql -v -race  -coverprofile=coverage.txt -covermode=atomic ./... --cockroach-binary cockroach
 
       - name: Upload Codecov
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v4
         with:
+          token: ${{ secrets.CODECOV_TOKEN }}
           files: ./coverage.txt
           flags: unittests
           env_vars: GO
           name: codecov-umbrella
           fail_ci_if_error: true
-          path_to_write_report: ./codecov_report.txt
           verbose: true

dbscan/dbscan_test.go

@@ -374,6 +374,25 @@ func TestScanRow_withAllowUnknownColumns_returnsRow(t *testing.T) {
 	assert.Equal(t, expected, *got)
 }
 
+func TestScanRow_withAllowUnknownColumns_unknownColumnType(t *testing.T) {
+	t.Parallel()
+	rows := queryRows(t, `
+		SELECT 'foo val' AS foo, 'test_val_1'::test_enum_type AS bar
+	`)
+	defer rows.Close() //nolint: errcheck
+	rows.Next()
+
+	got := &struct{ Foo string }{}
+	testAPIWithUnknownColumns, err := getAPI(dbscan.WithAllowUnknownColumns(true))
+	require.NoError(t, err)
+	err = testAPIWithUnknownColumns.ScanRow(got, rows)
+	require.NoError(t, err)
+	requireNoRowsErrorsAndClose(t, rows)
+
+	expected := struct{ Foo string }{Foo: "foo val"}
+	assert.Equal(t, expected, *got)
+}
+
 func TestMain(m *testing.M) {
 	exitCode := func() int {
 		flag.Parse()
@@ -387,6 +406,10 @@ func TestMain(m *testing.M) {
 			panic(err)
 		}
 		defer testDB.Close()
+		err = prepareTestDB(testDB)
+		if err != nil {
+			panic(err)
+		}
 		testAPI, err = getAPI()
 		if err != nil {
 			panic(err)
@@ -395,3 +418,11 @@ func TestMain(m *testing.M) {
 	}()
 	os.Exit(exitCode)
 }
+
+func prepareTestDB(testDB *pgxpool.Pool) (err error) {
+	_, err = testDB.Exec(ctx, `
+		CREATE TYPE test_enum_type AS ENUM ('test_val_1', 'test_val_2');
+	`)
+
+	return err
+}

dbscan/rowscanner.go

@@ -124,6 +124,12 @@ func startScanner(rs *RowScanner, dstValue reflect.Value) error {
 	)
 }
 
+type noOpScanType struct{}
+
+func (*noOpScanType) Scan(value interface{}) error {
+	return nil
+}
+
 func (rs *RowScanner) scanStruct(structValue reflect.Value) error {
 	if rs.scans == nil {
 		rs.scans = make([]interface{}, len(rs.columns))
@@ -132,7 +138,7 @@ func (rs *RowScanner) scanStruct(structValue reflect.Value) error {
 		fieldIndex, ok := rs.columnToFieldIndex[column]
 		if !ok {
 			if rs.api.allowUnknownColumns {
-				var tmp interface{}
+				var tmp noOpScanType
 				rs.scans[i] = &tmp
 				continue
 			}