Fixed #349; Column throw when constructed with nullptr

include/SQLiteCpp/Column.h

@@ -246,7 +246,7 @@ public:
      *
      * @see getString
      */
-    explicit operator std::string() const
+    operator std::string() const
     {
         return getString();
     }

include/SQLiteCpp/Statement.h

@@ -699,17 +699,15 @@ private:
      */
     sqlite3_stmt* getPreparedStatement() const;
 
-
-    /// Map of columns index by name (mutable so getColumnIndex can be const)
-    using TColumnNames = std::map<std::string, int>;
-
     std::string             mQuery;                 //!< UTF-8 SQL Query
     sqlite3*                mpSQLite;               //!< Pointer to SQLite Database Connection Handle
     TStatementPtr           mpPreparedStatement;    //!< Shared Pointer to the prepared SQLite Statement Object
     int                     mColumnCount{0};        //!< Number of columns in the result of the prepared statement
-    mutable TColumnNames    mColumnNames;           //!< Map of columns index by name (mutable so getColumnIndex can be const)
     bool                    mbHasRow{false};        //!< true when a row has been fetched with executeStep()
     bool                    mbDone{false};          //!< true when the last executeStep() had no more row to fetch
+    
+    /// Map of columns index by name (mutable so getColumnIndex can be const)
+    mutable std::map<std::string, int>  mColumnNames{};
 };
 
 

src/Column.cpp

@@ -30,6 +30,10 @@ Column::Column(const Statement::TStatementPtr& aStmtPtr, int aIndex) noexcept :
     mStmtPtr(aStmtPtr),
     mIndex(aIndex)
 {
+    if (!aStmtPtr)
+    {
+        throw SQLite::Exception("Statement was destroyed");
+    }
 }
 
 // Return the named assigned to this result column (potentially aliased)

src/Statement.cpp

@@ -264,13 +264,13 @@ int Statement::getColumnIndex(const char* apName) const
         }
     }
 
-    const TColumnNames::const_iterator iIndex = mColumnNames.find(apName);
+    const auto iIndex = mColumnNames.find(apName);
     if (iIndex == mColumnNames.end())
     {
         throw SQLite::Exception("Unknown column name.");
     }
 
-    return (*iIndex).second;
+    return iIndex->second;
 }
 
 const char * Statement::getColumnDeclaredType(const int aIndex) const

tests/Statement_test.cpp

@@ -119,7 +119,6 @@ TEST(Statement, moveConstructor)
     EXPECT_EQ(2, query.getColumnCount());
     SQLite::Statement moved = std::move(query);
     EXPECT_TRUE(query.getQuery().empty());
-    EXPECT_EQ(0, query.getColumnCount());
     EXPECT_FALSE(moved.getQuery().empty());
     EXPECT_EQ(2, moved.getColumnCount());
     // Execute
@@ -128,6 +127,16 @@ TEST(Statement, moveConstructor)
     EXPECT_FALSE(moved.isDone());
     EXPECT_FALSE(query.hasRow());
     EXPECT_FALSE(query.isDone());
+
+    // Const statement lookup
+    const auto const_query = std::move(moved);
+    auto index = const_query.getColumnIndex("value");
+    EXPECT_EQ(1, index);
+    EXPECT_NO_THROW(const_query.getColumn(index));
+
+    // Moved statements should throw
+    EXPECT_THROW(query.getColumnIndex("value"), SQLite::Exception);
+    EXPECT_THROW(query.getColumn(index), SQLite::Exception);
 }
 
 #endif