PatchOperation.Add throws an exception if the value is null.

[danieldespainTLS]

We are continuously addressing and improving the SDK, if possible, make sure the problem persist in the latest SDK version.

Describe the bug
Unable to PatchOperation.Add("/path", value) when the value is null.
Same as issue 2931 #2931, but when doing an .Add

To Reproduce
string? svar = null;
await container.PatchItemAsync(id, partitionKey, new List { PatchOperation.Add("/name", svar) });

Expected behavior
The value should be allowed to be null, and the JSON document in the container should get a "null" value for /name.

Actual behavior
System.Private.CoreLib: Exception while executing function: ReadDataFromCosmosDb. Anonymously Hosted DynamicMethods Assembly: The type arguments for method 'Microsoft.Azure.Cosmos.PatchOperation.Add(string, T)' cannot be inferred from the usage. Try specifying the type arguments explicitly.

Environment summary
SDK Version: 3.32.3
OS Version (e.g. Windows, Linux, MacOSX) MacOSX

Additional context
If I try to write:
PatchOperation.Add("/name", null)
then I get a compile error (same text as "actual behavior" above)

Similar to issue 2931 but that was for .Set. I think all of the patch methods should accept a null value since the JSON document supports nulls and it's reasonable to expect a POCO to have a null value.

The same JToken workaround from post 2931 works for .Add

[ealsur]

@aavasthy could you take a look? It seems we missed adding support for this on Add and Replace operations

[aavasthy]

@danieldespainTLS The error message you encountered isn't pointing to ArgumentNullException but it suggests that the type of the 'svar' variable cannot be inferred by the compiler. Please try to explicitly specify the type argument for the 'Add' method of the PatchOperation.

Updated code:

string? svar = null;
await container.PatchItemAsync(id, partitionKey, new List { PatchOperation.Add<string>("/name", svar)});

[ghost]

@danieldespainTLS this issue requires more information for the team to be able to help. In case this information is available, please add it and re-open the Issue.