AssemblyNameInfo.FullName does not include public key

[jkotas]

Repro

using System.Reflection;
using System.Reflection.Metadata;

var mscorlib = "mscorlib, Version=4.0.0.0, Culture=neutral, PublicKey=00000000000000000400000000000000";

Console.WriteLine(new AssemblyName(mscorlib).FullName);
Console.WriteLine(AssemblyNameInfo.Parse(mscorlib).FullName);

Actual result

mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
mscorlib, Version=4.0.0.0, Culture=neutral

Expected result

PublicKey (or PublicKeyToken) is included in AssemblyNameInfo.FullName

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[jkotas]

@adamsitnik I have run into this while working on #102036. I see that you have mentioned this behavior in the documentation, but it is not the behavior that I would expect.

Somewhat related to this issue is a problem with conversions of PublicKey to PublicKeyToken. In #102036, I ended up calling into AssemblyName for this conversion in number of places, but it does not look pretty. Would it make sense to have a public API for it?

[adamsitnik]

PublicKey (or PublicKeyToken) is included in AssemblyNameInfo.FullName

IIRC we did not want the AssemblyNameInfo to perform any conversions and validations of the PublicKey[Token].

Would including PublicKey in AssemblyNameInfo.FullName be enough for your scenario?

Have used it here just to let it be a key in the dictionary (and part of the info was missing) or did you also want to treat two AssemblyNameInfo instances, one with PublicKey and another with PublicKeyToken that map to the same PublicKeyToken as equal?

[jkotas]

IIRC we did not want the AssemblyNameInfo to perform any conversions and validations of the PublicKey[Token].

I do like that AssemblyNameInfo does not perform any implicit conversions of PublicKey[Token]. I think it is the right design decision.

There are situations where one needs to do an explicit PublicKey -> PublicKeyToken conversion. There is no straightforward way to do it. I think we may want to add an API for the explicit conversion.

Would including PublicKey in AssemblyNameInfo.FullName be enough for your scenario?

Yes, I would address the behavior that I did not expect. I assumed that AssemblyNameInfo.FullName/AssemblyNameInfo.Parse is going to roundtrip all (non-obsolete) properties.

Have used it here just to let it be a key in the dictionary

I have run into several different issues while coding my change. In the specific place you have linked, the missing conversion would just result into inefficiency (much longer public key stored into binary instead of public key token).

[adamsitnik]

Yes, I would address the behavior that I did not expect.

Great, then we agree on the solution.

When it comes to the fix I am currently busy with... backporting Full Framework with Security updates and finishing the PayloadReader API. I think I should be able to get back to this in +- 2 weeks.