Fix for #90

* When a slice that is `*sql.RawBytes`, `*[]byte` or `sql.Scanner` no errors will be returned.

HISTORY.md

@@ -1,6 +1,8 @@
 ## v7.1.0
 
 * [FIXED] Embedded pointers with property names that duplicate parent struct properties. [#23](https://github.com/doug-martin/goqu/issues/23)
+* [FIXED] Can't scan values using []byte or []string [#90](https://github.com/doug-martin/goqu/issues/90)
+    * When a slice that is `*sql.RawBytes`, `*[]byte` or `sql.Scanner` no errors will be returned. 
 
 ## v7.0.1
 

exec/query_executor.go

@@ -203,13 +203,19 @@ func (q QueryExecutor) ScanValContext(ctx context.Context, i interface{}) (bool,
 	}
 	val = reflect.Indirect(val)
 	if util.IsSlice(val.Kind()) {
-		return false, errScanValNonSlice
+		switch i.(type) {
+		case *sql.RawBytes: // do nothing
+		case *[]byte: // do nothing
+		case sql.Scanner: // do nothing
+		default:
+			return false, errScanValNonSlice
+		}
 	}
 	rows, err := q.QueryContext(ctx)
 	if err != nil {
 		return false, err
 	}
-	return NewScanner(rows).ScanVals(i)
+	return NewScanner(rows).ScanVal(i)
 }
 
 func (q QueryExecutor) rowsScanner(ctx context.Context) (Scanner, error) {

exec/scanner.go

@@ -13,6 +13,7 @@ type (
 	Scanner interface {
 		ScanStructs(i interface{}) (bool, error)
 		ScanVals(i interface{}) (bool, error)
+		ScanVal(i interface{}) (found bool, err error)
 	}
 	scanner struct {
 		rows *sql.Rows
@@ -76,28 +77,35 @@ func (q *scanner) ScanVals(i interface{}) (found bool, err error) {
 	defer q.rows.Close()
 	val := reflect.Indirect(reflect.ValueOf(i))
 	t, _, isSliceOfPointers := util.GetTypeInfo(i, val)
-	switch val.Kind() {
-	case reflect.Slice:
-		for q.rows.Next() {
-			found = true
-			row := reflect.New(t)
-			if err = q.rows.Scan(row.Interface()); err != nil {
-				return found, err
-			}
-			if isSliceOfPointers {
-				val.Set(reflect.Append(val, row))
-			} else {
-				val.Set(reflect.Append(val, reflect.Indirect(row)))
-			}
+	for q.rows.Next() {
+		found = true
+		row := reflect.New(t)
+		if err = q.rows.Scan(row.Interface()); err != nil {
+			return found, err
 		}
-	default:
-		for q.rows.Next() {
-			found = true
-			if err = q.rows.Scan(i); err != nil {
-				return false, err
-			}
+		if isSliceOfPointers {
+			val.Set(reflect.Append(val, row))
+		} else {
+			val.Set(reflect.Append(val, reflect.Indirect(row)))
 		}
+	}
+	return found, q.rows.Err()
+}
 
+// This will execute the SQL and append results to the slice.
+//    var ids []uint32
+//    if err := From("test").Select("id").ScanVals(&ids); err != nil{
+//        panic(err.Error()
+//    }
+//
+// i: Takes a pointer to a slice of primitive values.
+func (q *scanner) ScanVal(i interface{}) (found bool, err error) {
+	defer q.rows.Close()
+	for q.rows.Next() {
+		found = true
+		if err = q.rows.Scan(i); err != nil {
+			return false, err
+		}
 	}
 	return found, q.rows.Err()
 }

exec/scanner_test.go

@@ -3,6 +3,7 @@ package exec
 import (
 	"context"
 	"database/sql"
+	"encoding/json"
 	"fmt"
 	"testing"
 
@@ -707,6 +708,81 @@ func (cet *crudExecTest) TestScanVal() {
 	assert.Equal(t, ptrID, int64(1))
 }
 
+func (cet *crudExecTest) TestScanVal_withByteSlice() {
+	t := cet.T()
+	mDb, mock, err := sqlmock.New()
+	assert.NoError(t, err)
+
+	mock.ExpectQuery(`SELECT "name" FROM "items"`).
+		WithArgs().
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).FromCSVString("byte slice result"))
+
+	db := newMockDb(mDb)
+	e := newQueryExecutor(db, nil, `SELECT "name" FROM "items"`)
+
+	var bytes []byte
+	found, err := e.ScanVal(bytes)
+	assert.Equal(t, errScanValPointer, err)
+	assert.False(t, found)
+
+	found, err = e.ScanVal(&bytes)
+	assert.NoError(t, err)
+	assert.True(t, found)
+	assert.Equal(t, []byte("byte slice result"), bytes)
+}
+
+func (cet *crudExecTest) TestScanVal_withRawBytes() {
+	t := cet.T()
+	mDb, mock, err := sqlmock.New()
+	assert.NoError(t, err)
+
+	mock.ExpectQuery(`SELECT "name" FROM "items"`).
+		WithArgs().
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).FromCSVString("byte slice result"))
+
+	db := newMockDb(mDb)
+	e := newQueryExecutor(db, nil, `SELECT "name" FROM "items"`)
+
+	var bytes sql.RawBytes
+	found, err := e.ScanVal(bytes)
+	assert.Equal(t, errScanValPointer, err)
+	assert.False(t, found)
+
+	found, err = e.ScanVal(&bytes)
+	assert.NoError(t, err)
+	assert.True(t, found)
+	assert.Equal(t, sql.RawBytes("byte slice result"), bytes)
+}
+
+type JSONBoolArray []bool
+
+func (b *JSONBoolArray) Scan(src interface{}) error {
+	return json.Unmarshal(src.([]byte), b)
+}
+
+func (cet *crudExecTest) TestScanVal_withValuerSlice() {
+	t := cet.T()
+	mDb, mock, err := sqlmock.New()
+	assert.NoError(t, err)
+
+	mock.ExpectQuery(`SELECT "bools" FROM "items"`).
+		WithArgs().
+		WillReturnRows(sqlmock.NewRows([]string{"bools"}).FromCSVString(`"[true, false, true]"`))
+
+	db := newMockDb(mDb)
+	e := newQueryExecutor(db, nil, `SELECT "bools" FROM "items"`)
+
+	var bools JSONBoolArray
+	found, err := e.ScanVal(bools)
+	assert.Equal(t, errScanValPointer, err)
+	assert.False(t, found)
+
+	found, err = e.ScanVal(&bools)
+	assert.NoError(t, err)
+	assert.True(t, found)
+	assert.Equal(t, JSONBoolArray{true, false, true}, bools)
+}
+
 func TestCrudExecSuite(t *testing.T) {
 	suite.Run(t, new(crudExecTest))
 }