Access internal constructor outside the assembly-CodePudding

I reviewed the code of Specflow in github and found a tricky issue that I cannot understand.

Line 69 in https://github.com/SpecFlowOSS/SpecFlow/blob/master/TechTalk.SpecFlow/ScenarioContext.cs

internal ScenarioContext(IObjectContainer scenarioContainer, ScenarioInfo scenarioInfo, ITestObjectResolver testObjectResolver)

Line 97~100 in https://github.com/SpecFlowOSS/SpecFlow/blob/master/Tests/TechTalk.SpecFlow.PluginTests/Infrastructure/WindsorPluginTests.cs

            var context = new ScenarioContext(
                objectContainer.Object, 
                new ScenarioInfo("", "", Array.Empty<string>(), new OrderedDictionary()), 
                new WindsorTestObjectResolver());

The constructor of TechTalk.SpecFlow.ScenarioContext is internal which means it could only access in the TechTalk.SpecFlow.dll. Why it still can access in TechTalk.SpecFlow.PluginTests.Infrastructure.WindsorPluginTests class? TechTalk.SpecFlow.PluginTests.Infrastructure.WindsorPluginTests class is in TechTalk.SpecFlow.PluginTests.dll. They are in different assembly.

CodePudding user response：

Because of InternalsVisibleTo. This enables access to internal types, methods, etc. to every object calling from the authorized assembly.

In https://github.com/SpecFlowOSS/SpecFlow/blob/master/TechTalk.SpecFlow/AssemblyAttributes.cs the assembly TechTalk.SpecFlow is decorated with some of this attributes, exposing all the internal methods to the listed assemblies:

TechTalk.SpecFlow.RuntimeTests
TechTalk.SpecFlow.PluginTests

It's a very common and useful technique used to test methods that should not be accessible to anyone, but that need to be tested.