Assembly.GetType(string, bool, bool) throws unexpected FileLoadException on NET9 #113534
Description
Description
When using Assembly.GetType(string, bool, bool) (in NET9) you can get unexpected FileLoadException depending on the input.
Depending on the passed in string parameter the method either succeeds (or fails) to look up a type, or throws an exception. Throwing that exception under those circumstances is certainly unexpected.
According to the documentation a FileLoadException will occur when
FileLoadException
name requires a dependent assembly that was found but could not be loaded.
alas - again according to the documentation,
This method only searches the current assembly instance
Specifically this occurs when using mscorlib as assembly to call things on. That assembly certainly should NOT have a problem "loading".
Reproduction Steps
Simple console program demonstrating the issue:
namespace Foo {
internal class Program {
static void Main(string[] args) {
var mscorLibAssembly = typeof(string).Assembly;
mscorLibAssembly.GetType("a,b", false, false); // wont throw
mscorLibAssembly.GetType("a,b,c", false, false); // will throw
}
}
}It seems, as soon as there are three (or more) , in the name parameter the method invocation throws.
Expected behavior
The method should certainly not throw a FileLoadException - because that indicates an issue with the probed assembly (here mscorlib) itself.
It might be reasonable to throw an ArgumentException because at least the docs state that this might occur
ArgumentException
name is invalid.
although "invalid" is not explained any further.
Preferably the method should not throw and just return null for a found type if the input is gibberish. Other runtimes - specifically NetFramework - simply returned null here.
Actual behavior
The method throws an unexpected exception FileLoadException on certain parameters.
Regression?
Yes. The method - and example code - will not throw an exception under previous versions of .NET (checked with .NET Framework 4.7.2 & .NET 8).
Known Workarounds
none
Configuration
NET 9.0.2
Other information
No response