Cache is never populated in ComponentDesigner.ShadowPropertyCollection.cs

.NET version

8.0.0-alpha.1.22559.2

However, the situation I am reporting is not tied to a specific .NET version.

Did it work in .NET Framework?

No

Did it work in any of the earlier releases of .NET Core or .NET 5+?

no

Issue description

The ShadowPropertyCollection class contains a private field called _descriptors which, if I understand the original intent correctly, is supposed to be used as a cache of PropertyDescriptor. The flow is supposed to be like this:

• the first-time a given property descriptor is requested, the value is calculated in the private PropertyDescriptor GetShadowedPropertyDescriptor(string propertyName) private method
• this value is added to the cache
• if the same property descriptor is subsequently requested the cached value is returned

However, what I observe when reading the code of this private method is that the calculated value is NOT added to the cache and therefore it is re-calculated each time the same descriptor is requested.

@elachlan, @dreddy-work and myself had a discussion about this and we concluded that it made more sense to raise a separate issue about this rather than simply fix it as part of #8222.

If the conclusion is that we want to fix the flawed logic, I will be happy to volunteer a PR.

Steps to reproduce

To be clear, the current logic works without problem and returns the expected result. It’s just that we pay a performance penalty if the same descriptor is requested multiple times.

[merriemcgaw]

We’d like to do a bit of investigation on the VS side of things so we can make sure that we don’t run into something unexpected.

[dreddy-work]

We haven’t got chance to go over this yet. It may have to wait for some more time.