[sql] Database recovery system for Shortcuts.

sql/recovery_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sql/recovery.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <string>
@@ skipping 749 matching lines @@
   std::unique_ptr<sql::Recovery> recovery =
       sql::Recovery::Begin(&db(), db_path());
   ASSERT_TRUE(recovery.get());
 
   // In the current implementation, the PRAGMA successfully runs with no result
   // rows.  Running with a single result of |0| is also acceptable.
   sql::Statement s(recovery->db()->GetUniqueStatement("PRAGMA mmap_size"));
   EXPECT_TRUE(!s.Step() || !s.ColumnInt64(0));
 }
 
+TEST_F(SQLRecoveryTest, RecoverDatabase) {
+  // As a side effect, AUTOINCREMENT creates the sqlite_sequence table for
+  // RecoverDatabase() to handle.
+  ASSERT_TRUE(db().Execute(
+      "CREATE TABLE x (id INTEGER PRIMARY KEY AUTOINCREMENT, v TEXT)"));
+  EXPECT_TRUE(db().Execute("INSERT INTO x (v) VALUES ('turtle')"));
+  EXPECT_TRUE(db().Execute("INSERT INTO x (v) VALUES ('truck')"));
+  EXPECT_TRUE(db().Execute("INSERT INTO x (v) VALUES ('trailer')"));
+
+  // This table needs index and a unique index to work.
+  ASSERT_TRUE(db().Execute("CREATE TABLE y (name TEXT, v TEXT)"));
+  ASSERT_TRUE(db().Execute("CREATE UNIQUE INDEX y_name ON y(name)"));
+  ASSERT_TRUE(db().Execute("CREATE INDEX y_v ON y(v)"));
+  EXPECT_TRUE(db().Execute("INSERT INTO y VALUES ('jim', 'telephone')"));
+  EXPECT_TRUE(db().Execute("INSERT INTO y VALUES ('bob', 'truck')"));
+  EXPECT_TRUE(db().Execute("INSERT INTO y VALUES ('dean', 'trailer')"));
+
+  // View which is the intersection of [x.v] and [y.v].
+  ASSERT_TRUE(db().Execute(
+      "CREATE VIEW v AS SELECT x.v FROM x, y WHERE x.v = y.v"));
+
+  // When an element is deleted from [x], trigger a delete on [y].  Between the
+  // BEGIN and END, [old] stands for the deleted rows from [x].
+  ASSERT_TRUE(db().Execute("CREATE TRIGGER t AFTER DELETE ON x "
+                           "BEGIN DELETE FROM y WHERE y.v = old.v; END"));
+
+  // Save aside a copy of the original schema, verifying that it has the created
+  // items plus the sqlite_sequence table.
+  const std::string orig_schema(GetSchema(&db()));
+  ASSERT_EQ(6, std::count(orig_schema.begin(), orig_schema.end(), '\n'));
+
+  const char kXSql[] = "SELECT * FROM x ORDER BY 1";
+  const char kYSql[] = "SELECT * FROM y ORDER BY 1";
+  const char kVSql[] = "SELECT * FROM v ORDER BY 1";
+  EXPECT_EQ("1|turtle\n2|truck\n3|trailer",
+            ExecuteWithResults(&db(), kXSql, "|", "\n"));
+  EXPECT_EQ("bob|truck\ndean|trailer\njim|telephone",
+            ExecuteWithResults(&db(), kYSql, "|", "\n"));
+  EXPECT_EQ("trailer\ntruck", ExecuteWithResults(&db(), kVSql, "|", "\n"));
+
+  // Database handle is valid before recovery, poisoned after.
+  const char kTrivialSql[] = "SELECT COUNT(*) FROM sqlite_master";
+  EXPECT_TRUE(db().IsSQLValid(kTrivialSql));
+  sql::Recovery::RecoverDatabase(&db(), db_path());
+  EXPECT_FALSE(db().IsSQLValid(kTrivialSql));
+
+  // Since the database was not corrupt, the entire schema and all
+  // data should be recovered.
+  ASSERT_TRUE(Reopen());
+  ASSERT_EQ(orig_schema, GetSchema(&db()));
+  EXPECT_EQ("1|turtle\n2|truck\n3|trailer",
+            ExecuteWithResults(&db(), kXSql, "|", "\n"));
+  EXPECT_EQ("bob|truck\ndean|trailer\njim|telephone",
+            ExecuteWithResults(&db(), kYSql, "|", "\n"));
+  EXPECT_EQ("trailer\ntruck", ExecuteWithResults(&db(), kVSql, "|", "\n"));
+
+  // Test that the trigger works.
+  ASSERT_TRUE(db().Execute("DELETE FROM x WHERE v = 'truck'"));
+  EXPECT_EQ("1|turtle\n3|trailer",
+            ExecuteWithResults(&db(), kXSql, "|", "\n"));
+  EXPECT_EQ("dean|trailer\njim|telephone",
+            ExecuteWithResults(&db(), kYSql, "|", "\n"));
+  EXPECT_EQ("trailer", ExecuteWithResults(&db(), kVSql, "|", "\n"));
+}
+
 }  // namespace