支持对scan后rows.Err()检查 (#144)

scanner/scanner.go

@@ -32,6 +32,8 @@ type Rows interface {
 	Next() bool
 
 	Scan(dest ...interface{}) error
+
+	Err() error
 }
 
 const (
@@ -329,6 +331,10 @@ func resolveDataFromRows(rows Rows) ([]map[string]interface{}, error) {
 		}
 		result = append(result, mp)
 	}
+	err = rows.Err()
+	if nil != err {
+		return nil, err
+	}
 	return result, nil
 }
 

scanner/scanner_test.go

@@ -1,6 +1,7 @@
 package scanner
 
 import (
+	"context"
 	"database/sql"
 	"encoding/json"
 	"errors"
@@ -987,7 +988,9 @@ type fakeRows struct {
 	idx     int
 }
 
+var gCtx context.Context = context.Background()
 var errCloseForTest = errors.New("just for test")
+var errCancelForTest = errors.New("context canceled")
 
 func (r *fakeRows) Close() error {
 	return errCloseForTest
@@ -1020,6 +1023,14 @@ func (r *fakeRows) Scan(dt ...interface{}) (err error) {
 	return nil
 }
 
+func (r *fakeRows) Err() error {
+	err := gCtx.Err()
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func TestScanNotSettable(t *testing.T) {
 	should := require.New(t)
 	err := Scan(&fakeRows{}, nil)
@@ -1076,6 +1087,31 @@ func TestScanMock(t *testing.T) {
 	should.Equal(24, boys[1].Age)
 }
 
+func TestScanCtxErr(t *testing.T) {
+	should := require.New(t)
+	scannn := &fakeRows{
+		columns: []string{"name", "age"},
+		dataset: [][]interface{}{
+			{"deen", 23},
+			{"caibirdme", 24},
+		},
+	}
+	type curdBoy struct {
+		Name string `ddb:"name"`
+		Age  int    `ddb:"age"`
+	}
+	var boys []curdBoy
+	defaultTag := DefaultTagName
+	userDefinedTagName = &defaultTag
+
+	var cancle context.CancelFunc
+	gCtx, cancle = context.WithCancel(gCtx)
+	cancle()
+	err := Scan(scannn, &boys)
+	should.Equal(errCancelForTest.Error(), err.Error())
+	gCtx = context.Background()
+}
+
 func TestScanEmpty(t *testing.T) {
 	should := require.New(t)
 	scannn := &fakeRows{}