adding Merge method to Batch

index.go

@@ -102,6 +102,18 @@ func (b *Batch) Reset() {
 	b.internal.Reset()
 }
 
+// Merge performs the merge of the internal Index.Batch
+// of the given batch to the self.
+func (b *Batch) Merge(other *Batch) {
+	for k, v := range other.internal.IndexOps {
+		b.internal.IndexOps[k] = v
+	}
+
+	for k, v := range other.internal.InternalOps {
+		b.internal.InternalOps[k] = v
+	}
+}
+
 // An Index implements all the indexing and searching
 // capabilities of bleve.  An Index can be created
 // using the New() and Open() methods.

index_test.go

@@ -1815,3 +1815,72 @@ func TestIndexAdvancedCountMatchSearch(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestMatchMerge(t *testing.T) {
+	defer func() {
+		err := os.RemoveAll("testidx")
+		if err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	index, err := New("testidx", NewIndexMapping())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	doca := map[string]interface{}{
+		"name": "scorcher",
+		"desc": "cbft",
+	}
+	batcha := index.NewBatch()
+	err = batcha.Index("a", doca)
+	if err != nil {
+		t.Error(err)
+	}
+	batcha.SetInternal([]byte("batch_a"), []byte("batch_a_value"))
+
+	docb := map[string]interface{}{
+		"name": "updc down",
+		"desc": "bleve",
+	}
+
+	batchb := index.NewBatch()
+	err = batchb.Index("b", docb)
+	if err != nil {
+		t.Error(err)
+	}
+	batchb.SetInternal([]byte("batch_b"), []byte("batch_b_value"))
+
+	batcha.Merge(batchb)
+
+	err = index.Batch(batcha)
+	if err != nil {
+		t.Error(err)
+	}
+
+	val, err := index.GetInternal([]byte("batch_b"))
+	if err != nil {
+		t.Error(err)
+	}
+
+	if string(val) != "batch_b_value" {
+		t.Errorf("expected 'batch_b_value', got '%s'", val)
+	}
+
+	val, err = index.GetInternal([]byte("batch_a"))
+	if err != nil {
+		t.Error(err)
+	}
+	if string(val) != "batch_a_value" {
+		t.Errorf("expected 'batch_a_value', got '%s'", val)
+	}
+
+	val, err = index.GetInternal([]byte("status"))
+	if err != nil {
+		t.Error(err)
+	}
+	if val != nil {
+		t.Errorf("expected nil, got '%s'", val)
+	}
+}