Fix multi-query resultset iteration

This uses an ugly hack to keep the standard rows iterator from closing the
HTTP body when it reaches the end: It sets the body to nil.

I think there's room now to consolidate the `rows` and `multiQueriesRows`.
My initial thought was to expand `rows`, but now that I have two
implementations, I believe it would make more sense instead to consolidate
everything in to `multiQueriesRows`.  It already has a few special cases
anyway.

db_live_test.go

@@ -52,16 +52,51 @@ func TestQueries_1_x(t *testing.T) {
 	}
 }
 
-// func TestQueries_2_x(t *testing.T) {
-// 	dsn := os.Getenv("KIVIK_TEST_DSN_COUCH23")
-// 	if dsn == "" {
-// 		dsn = os.Getenv("KIVIK_TEST_DSN_COUCH22")
-// 	}
-// 	if dsn == "" {
-// 		t.Skip("Neither KIVIK_TEST_DSN_COUCH22 nor KIVIK_TEST_DSN_COUCH23 configured")
-// 	}
+func TestQueries_2_x(t *testing.T) {
+	dsn := os.Getenv("KIVIK_TEST_DSN_COUCH23")
+	if dsn == "" {
+		dsn = os.Getenv("KIVIK_TEST_DSN_COUCH22")
+	}
+	if dsn == "" {
+		t.Skip("Neither KIVIK_TEST_DSN_COUCH22 nor KIVIK_TEST_DSN_COUCH23 configured")
+	}
 
-// }
+	client, err := kivik.New("couch", dsn)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	db := client.DB(context.Background(), "_users")
+	rows, err := db.AllDocs(context.Background(), map[string]interface{}{
+		"queries": []map[string]interface{}{
+			{},
+			{},
+		},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer rows.Close() // nolint:errcheck
+	result := make([]interface{}, 0)
+	for rows.Next() {
+		if rows.EOQ() {
+			result = append(result, map[string]interface{}{
+				"EOQ":        true,
+				"total_rows": rows.TotalRows(),
+			})
+			continue
+		}
+		result = append(result, map[string]interface{}{
+			"_id": rows.ID(),
+		})
+	}
+	if err := rows.Err(); err != nil {
+		t.Fatal(err)
+	}
+	if d := testy.DiffInterface(testy.Snapshot(t), result); d != nil {
+		t.Error(d)
+	}
+}
 
 // func TestQueries_3_x(t *testing.T) {
 // 	dsn := os.Getenv("KIVIK_TEST_DSN_COUCH30")

iter.go

@@ -262,6 +262,10 @@ func (i *iter) nextRow(row interface{}) error {
 
 func (i *iter) Close() error {
 	atomic.StoreInt32(&i.closed, 1)
+	// body will be nil if we're iterating over a multi-query resultset.
+	if i.body == nil {
+		return nil
+	}
 	return i.body.Close()
 }
 

rows.go

@@ -215,6 +215,7 @@ func (r *multiQueriesRows) begin() error {
 			Closer: r.r,
 		}
 		r.rows = newRows(r.ctx, in).(*rows)
+		r.rows.body = nil
 		r.rows.dec = json.NewDecoder(in)
 		return r.rows.begin()
 	}
@@ -223,6 +224,7 @@ func (r *multiQueriesRows) begin() error {
 		return err
 	}
 	r.rows = newRows(r.ctx, r.r).(*rows)
+	r.rows.body = nil
 	r.rows.iter.dec = r.dec
 	return r.rows.iter.begin()
 }
@@ -249,6 +251,7 @@ func (r *multiQueriesRows) nextQuery() error {
 	}
 	r.queryIndex++
 	r.rows = rows
+	r.rows.body = nil
 	return nil
 }
 

testdata/TestQueries_2_x

@@ -0,0 +1,16 @@
+([]interface {}) (len=4) {
+  (map[string]interface {}) (len=1) {
+    (string) (len=3) "_id": (string) (len=13) "_design/_auth"
+  },
+  (map[string]interface {}) (len=2) {
+    (string) (len=3) "EOQ": (bool) true,
+    (string) (len=10) "total_rows": (int64) 1
+  },
+  (map[string]interface {}) (len=1) {
+    (string) (len=3) "_id": (string) (len=13) "_design/_auth"
+  },
+  (map[string]interface {}) (len=2) {
+    (string) (len=3) "EOQ": (bool) true,
+    (string) (len=10) "total_rows": (int64) 1
+  }
+}