Added parameter 'clear_bound_vars', so we could reset the statement without clearing bound variables, so and current row is reset to the beginning.

It is used to support the Andorid' sqlite cursor feature which could move the cursor around the result set.

BUG=
TEST=Added a new test.
TBR=agl,akalin,michaeln

Review URL: http://codereview.chromium.org/10171014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@133985 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 35 insertions, 12 deletions

diff --git a/sql/connection_unittest.cc b/sql/connection_unittest.cc
index 96cc25b..97dd152 100644
--- a/sql/connection_unittest.cc
+++ b/sql/connection_unittest.cc
@@ -195,7 +195,7 @@ TEST_F(SQLConnectionTest, RazePageSize) {
 
   // After raze, page_size should still match the indicated value.
   ASSERT_TRUE(db().Raze());
-  s.Reset();
+  s.Reset(true);
   ASSERT_TRUE(s.Step());
   ASSERT_EQ(kPageSize, s.ColumnInt(0));
 }
@@ -218,7 +218,7 @@ TEST_F(SQLConnectionTest, RazeMultiple) {
   ASSERT_TRUE(db().Raze());
 
   // The second connection sees the updated database.
-  s.Reset();
+  s.Reset(true);
   ASSERT_TRUE(s.Step());
   ASSERT_EQ(0, s.ColumnInt(0));
 }
diff --git a/sql/statement.cc b/sql/statement.cc
index 626c15b..3616dcc 100644
--- a/sql/statement.cc
+++ b/sql/statement.cc
@@ -28,11 +28,11 @@ Statement::~Statement() {
   // Free the resources associated with this statement. We assume there's only
   // one statement active for a given sqlite3_stmt at any time, so this won't
   // mess with anything.
-  Reset();
+  Reset(true);
 }
 
 void Statement::Assign(scoped_refptr<Connection::StatementRef> ref) {
-  Reset();
+  Reset(true);
   ref_ = ref;
 }
 
@@ -61,12 +61,13 @@ bool Statement::Step() {
   return CheckError(sqlite3_step(ref_->stmt())) == SQLITE_ROW;
 }
 
-void Statement::Reset() {
+void Statement::Reset(bool clear_bound_vars) {
   if (is_valid()) {
     // We don't call CheckError() here because sqlite3_reset() returns
     // the last error that Step() caused thereby generating a second
     // spurious error callback.
-    sqlite3_clear_bindings(ref_->stmt());
+    if (clear_bound_vars)
+      sqlite3_clear_bindings(ref_->stmt());
     sqlite3_reset(ref_->stmt());
   }
 
diff --git a/sql/statement.h b/sql/statement.h
index 92d1ef2..269684f 100644
--- a/sql/statement.h
+++ b/sql/statement.h
@@ -87,9 +87,9 @@ class SQL_EXPORT Statement {
   //   return s.Succeeded();
   bool Step();
 
-  // Resets the statement to its initial condition. This includes clearing all
-  // the bound variables and any current result row.
-  void Reset();
+  // Resets the statement to its initial condition. This includes any current
+  // result row, and also the bound variables if the |clear_bound_vars| is true.
+  void Reset(bool clear_bound_vars);
 
   // Returns true if the last executed thing in this statement succeeded. If
   // there was no last executed thing or the statement is invalid, this will
diff --git a/sql/statement_unittest.cc b/sql/statement_unittest.cc
index b6b6aa8..0028b9d 100644
--- a/sql/statement_unittest.cc
+++ b/sql/statement_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -88,14 +88,14 @@ TEST_F(SQLStatementTest, Run) {
 
   // Run should fail since this produces output, and we should use Step(). This
   // gets a bit wonky since sqlite says this is OK so succeeded is set.
-  s.Reset();
+  s.Reset(true);
   s.BindInt(0, 3);
   EXPECT_FALSE(s.Run());
   EXPECT_EQ(SQLITE_ROW, db().GetErrorCode());
   EXPECT_TRUE(s.Succeeded());
 
   // Resetting it should put it back to the previous state (not runnable).
-  s.Reset();
+  s.Reset(true);
   EXPECT_FALSE(s.Succeeded());
 
   // Binding and stepping should produce one row.
@@ -120,3 +120,25 @@ TEST_F(SQLStatementTest, BasicErrorCallback) {
   EXPECT_EQ(SQLITE_MISMATCH, sqlite_error());
   reset_error();
 }
+
+TEST_F(SQLStatementTest, Reset) {
+  ASSERT_TRUE(db().Execute("CREATE TABLE foo (a, b)"));
+  ASSERT_TRUE(db().Execute("INSERT INTO foo (a, b) VALUES (3, 12)"));
+  ASSERT_TRUE(db().Execute("INSERT INTO foo (a, b) VALUES (4, 13)"));
+
+  sql::Statement s(db().GetUniqueStatement(
+      "SELECT b FROM foo WHERE a = ? "));
+  s.BindInt(0, 3);
+  ASSERT_TRUE(s.Step());
+  EXPECT_EQ(12, s.ColumnInt(0));
+  ASSERT_FALSE(s.Step());
+
+  s.Reset(false);
+  // Verify that we can get all rows again.
+  ASSERT_TRUE(s.Step());
+  EXPECT_EQ(12, s.ColumnInt(0));
+  EXPECT_FALSE(s.Step());
+
+  s.Reset(true);
+  ASSERT_FALSE(s.Step());
+}