How to get the testId generated by Visual Studio in a .loadtest file
During these days I have been working on a tool that automates the execution of a load test.
Our objective was to parse a .loadtest template file, based on a template, which has been configured for a specific scenario with a set of counters. Once we have parsed the template we are ready to add the TestMix node and a TestProfile node for each test that we want to execute from those defined on test assembly.
The Obstacle
When I was creating the TestProfile node, I realized that each unit test has an specific Id (represented by a unique identifier a.k.a Guid). What I didn't noticed until we've run the load test is that this identifier was generated dynamically by Visual Studio.
We tried going under the hood , unluckily, using reflector to analyze some of Visual Studio assemblies in order to find how these identifiers were generated.
The suggested workaround
Searching on the web I found a post with a method which generates the Guid we’re looking for:
private static Guid GetGuidFromString(string value)
{
SHA1CryptoServiceProvider provider = new SHA1CryptoServiceProvider();
byte[] buffer1 = provider.ComputeHash(Encoding.Unicode.GetBytes(value));
byte[] buffer2 = new byte[0x10];
Array.Copy(buffer1, buffer2, 0×10);
return new Guid(buffer2);
}Using the recently created function we’re able to retrieve the Guid for a given assembly as I’m showing below
private static IList<TestEntry> GetUnitTests()
{
IList<TestEntry> unitTests = new List<TestEntry>();
Assembly assembly = Assembly.LoadFrom(“Tests\\PerformanceTests.dll“);
Type[] assemblyTypes = assembly.GetTypes();
foreach (Type type in assemblyTypes)
{
if (type.IsClass &&
type.GetCustomAttributes(typeof(TestClassAttribute), false).Length > 0)
{
MethodInfo[] info = type.GetMethods();
foreach (MethodInfo m in info)
{
if (m.GetCustomAttributes(typeof(TestMethodAttribute), false).Length > 0)
{
Guid testGuid = GetGUIDFromString(type.FullName + “.“ + m.Name);
unitTests.Add(new TestEntry(testGuid, m.Name));
}
}
}
}
return unitTests;
}Hope you find it useful!