mysqlc: Fix query of cursor position in result set

Fix queries like "IsAfterLast" in result sets of prepared statements in
the mysql driver.

Cursor position is stored in the driver, since the mysql C driver does
not support the query of the cursor position.

The cursor position works the following way:
- 0 means the cursor is on "BeforeFirst". In that state calling of
getXXX() methods is user error.
- 1 means the first row is already fetched.
- n means the last fow is fetched, where n is the total number of rows
in the result set.
- Everything bigger than n is "AfterLast"

Change-Id: I131f2042606897019cc0f868dbc4151faf4850ac
Reviewed-on: https://gerrit.libreoffice.org/76549
Tested-by: Jenkins
Reviewed-by: Tamás Bunth <btomi96@gmail.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/connectivity/qa/connectivity/mysql/mysql.cxx b/connectivity/qa/connectivity/mysql/mysql.cxx
index 3e48ce5b3750..24af725b0110 100644
--- a/connectivity/qa/connectivity/mysql/mysql.cxx
+++ b/connectivity/qa/connectivity/mysql/mysql.cxx
@@ -54,6 +54,7 @@ public:
     void testDBMetaData();
     void testTimestampField();
     void testNumericConversionPrepared();
+    void testPreparedStmtIsAfterLast();
 
     CPPUNIT_TEST_SUITE(MysqlTestDriver);
     CPPUNIT_TEST(testDBConnection);
@@ -63,6 +64,7 @@ public:
     CPPUNIT_TEST(testDBMetaData);
     CPPUNIT_TEST(testTimestampField);
     CPPUNIT_TEST(testNumericConversionPrepared);
+    CPPUNIT_TEST(testPreparedStmtIsAfterLast);
     CPPUNIT_TEST_SUITE_END();
 };
 
@@ -405,6 +407,45 @@ void MysqlTestDriver::testNumericConversionPrepared()
     xStatement->executeUpdate("DROP TABLE myTestTable");
 }
 
+/**
+ * Test cursor positioning method isAfterLast in case of using prepared
+ * statement.
+ */
+void MysqlTestDriver::testPreparedStmtIsAfterLast()
+{
+    Reference<XConnection> xConnection = m_xDriver->connect(m_sUrl, m_infos);
+    if (!xConnection.is())
+        CPPUNIT_ASSERT_MESSAGE("cannot connect to data source!", xConnection.is());
+    uno::Reference<XStatement> xStatement = xConnection->createStatement();
+    CPPUNIT_ASSERT(xStatement.is());
+    xStatement->executeUpdate("DROP TABLE IF EXISTS myTestTable");
+
+    // create test table
+    xStatement->executeUpdate("CREATE TABLE myTestTable (id INTEGER PRIMARY KEY)");
+    Reference<XPreparedStatement> xPrepared
+        = xConnection->prepareStatement(OUString{ "INSERT INTO myTestTable VALUES (?)" });
+    Reference<XParameters> xParams(xPrepared, UNO_QUERY);
+    constexpr int ROW_COUNT = 6;
+    for (int i = 0; i < ROW_COUNT; ++i)
+    {
+        xParams->setShort(1, i);
+        xPrepared->executeUpdate();
+    }
+
+    // query test table
+    xPrepared = xConnection->prepareStatement("SELECT id from myTestTable where id = 3");
+    Reference<XResultSet> xResultSet = xPrepared->executeQuery();
+
+    // There should be exactly one row, therefore IsAfterLast is false at first.
+    xResultSet->next();
+    CPPUNIT_ASSERT(!xResultSet->isAfterLast());
+
+    // attempt to fetch more data
+    bool hasData = xResultSet->next();
+    CPPUNIT_ASSERT(!hasData); // now we are on "AfterLast"
+    CPPUNIT_ASSERT(xResultSet->isAfterLast());
+}
+
 CPPUNIT_TEST_SUITE_REGISTRATION(MysqlTestDriver);
 
 CPPUNIT_PLUGIN_IMPLEMENT();