[sqlite] Fix bug in how recover virtual table handles empty.

third_party/sqlite/src/test/recover.test

 # 2012 January 11 {}
 #
 # The author disclaims copyright to this source code.  In place of
 # a legal notice, here is a blessing:
 #
 #    May you do good and not evil.
 #    May you find forgiveness for yourself and forgive others.
 #    May you share freely, never taking more than you give.
 #
 #***********************************************************************
@@ skipping 92 matching lines @@
     DROP TABLE IF EXISTS temp.leaf_recover;
     CREATE VIRTUAL TABLE temp.leaf_recover USING recover(
       leaf,
       t TEXT,
       n INTEGER
     );
   }
   execsql {SELECT t, n FROM leaf_recover ORDER BY rowid}
 } {{Leaf-node-generating line 0} 0 {Leaf-node-generating line 1} 1 {Leaf-node-generating line 2} 2 {Leaf-node-generating line 3} 3 {Leaf-node-generating line 4} 4 {Leaf-node-generating line 5} 5 {Leaf-node-generating line 6} 6 {Leaf-node-generating line 7} 7 {Leaf-node-generating line 8} 8 {Leaf-node-generating line 9} 9}
 
+# Empty table gives empty results.
+do_test recover-leaf-2.0 {
+  db close
+  sqlite3 db test.db
+  generate "empty" "Leaf-node-generating line " 0
+
+  db eval {
+    DROP TABLE IF EXISTS temp.leaf_recover;
+    CREATE VIRTUAL TABLE temp.leaf_recover USING recover(
+      empty,
+      t TEXT,
+      n INTEGER
+    );
+  }
+  execsql {SELECT t, n FROM leaf_recover ORDER BY rowid}
+} {}
+
 # Single level of interior node.
 do_test recover-interior-1.0 {
   db close
   sqlite3 db test.db
   generate "interior" "Interior-node-generating line " 100
 
   db eval {
     DROP TABLE IF EXISTS temp.interior_recover;
     CREATE VIRTUAL TABLE temp.interior_recover USING recover(
       interior,
@@ skipping 15 matching lines @@
     CREATE VIRTUAL TABLE temp.interior2_recover USING recover(
       interior2,
       t TEXT,
       n INTEGER
     );
   }
   execsql {SELECT t, n FROM interior2_recover WHERE (rowid%500)=0 ORDER BY rowid}
 } {{Interior-node-generating line 499} 499 {Interior-node-generating line 999} 999 {Interior-node-generating line 1499} 1499 {Interior-node-generating line 1999} 1999 {Interior-node-generating line 2499} 2499 {Interior-node-generating line 2999} 2999 {Interior-node-generating line 3499} 3499 {Interior-node-generating line 3999} 3999 {Interior-node-generating line 4499} 4499 {Interior-node-generating line 4999} 4999}
 
 finish_test