You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: datatype_mapper_test.go
    path of file: ./repos/rudder-server/warehouse/integrations/snowflake
    
    the code of the file until where you have to start completion: package snowflake

import (
	"database/sql"
	"testing"

	"github.com/stretchr/testify/require"
)

func TestCalculateDat
    
func TestCalculateDataType(t *testing.T) {
	testCases := []struct {
		columnType   string
		numericScale sql.NullInt64
		expected     string
		exists       bool
	}{
		{"VARCHAR", sql.NullInt64{}, "string", true},
		{"INT", sql.NullInt64{}, "int", true},
		{"INT", sql.NullInt64{Int64: 2, Valid: true}, "float", true},
		{"UNKNOWN", sql.NullInt64{}, "", false},
	}

	for _, tc := range testCases {
		dataType, exists := calculateDataType(tc.columnType, tc.numericScale)
		require.Equal(t, tc.expected, dataType)
		require.Equal(t, tc.exists, exists)
	}
}