column_count, column_name, close statement

spec/driver_spec.cr

@@ -6,6 +6,10 @@ ensure
   File.delete(DB_FILENAME)
 end
 
+def with_mem_db
+  yield DB.open "sqlite3", {"database": ":memory:"}
+end
+
 def sql(s : String)
   "#{s.inspect}"
 end
@@ -119,4 +123,30 @@ describe Driver do
       assert_single_read result_set, String, "hello"
     end
   end
+
+  it "gets column count" do
+    with_mem_db do |db|
+      db.exec_non_query "create table person (name string, age integer)"
+      db.exec_non_query %(insert into person values ("foo", 10))
+
+      run = false
+      db.exec_query_each "select * from person" do |result_set|
+        run = true
+        result_set.column_count.should eq(2)
+      end
+      run.should be_true
+    end
+  end
+
+  it "gets column name" do
+    with_mem_db do |db|
+      db.exec_non_query "create table person (name string, age integer)"
+      db.exec_non_query %(insert into person values ("foo", 10))
+
+      db.exec_query_each("select * from person") do |result_set|
+        result_set.column_name(0).should eq("name")
+        result_set.column_name(1).should eq("age")
+      end
+    end
+  end
 end

src/sqlite3/result_set2.cr

@@ -57,6 +57,14 @@ class SQLite3::ResultSet2 < DB::ResultSet
     end
   end
 
+  def column_count
+    LibSQLite3.column_count(self)
+  end
+
+  def column_name(index)
+    String.new LibSQLite3.column_name(self, index)
+  end
+
   def to_unsafe
     @statement.to_unsafe
   end

src/sqlite3/statement2.cr

@@ -8,6 +8,10 @@ class SQLite3::Statement2 < DB::Statement
     LibSQLite3.reset(self)
   end
 
+  protected def on_close
+    check LibSQLite3.finalize(self)
+  end
+
   protected def add_parameter(index : Int32, value)
     bind_arg(index, value)
   end