Fix handling of parameters with default null #85
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| .Parameters.Select(x => | ||
| { | ||
| var dispString = x.ToDisplayString(FullyQualifiedDisplayFormat); | ||
| if (x.HasExplicitDefaultValue && x.ExplicitDefaultValue is null && x.NullableAnnotation != NullableAnnotation.Annotated) |
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ToDisplayString can take a NullableFlowState parameter - could you perhaps use that and avoid the regex?
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The NullableFlowState is only available for ITypeSymbol, but here we have a IParameterSymbol, so that overload can't be used.
It's a bit weird, because our FullyQualifiedDisplayFormat already includes SymbolDisplayMiscellaneousOptions.IncludeNullableReferenceTypeModifier, but for some reason the questionmark is missing in the output.
But if there's a better solution for the regex, I'm all for it.
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Oh, that's disappointing. It's particularly odd when IParameterSymbol has a Type property that exposes the parameter's type via an ITypeSymbol 😵💫
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I have had to do a bit of regex on parameter symbols in my most recent PR in this repo, and part of the change involves regenerating the type part of a parameter (so we can qualify references to generated interfaces), so in that case the ITypeSymbol will be available 🤷♀️.
It's difficult when the PRs start to stack up.
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I get what you mean now. Sorry, I'm not very experienced with the CodeAnalysis stuff. Sadly the NullableFlowState parameter doesn't seem to do anything.
I found another approach by using the DisplayParts instead of parsing with regex.
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I like the DisplayParts approach. I think I might do the same in my PR and get rid of my regex too. It wasn't feeling very future-proof.
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This in an attempt of improving handling of nullable parameters.
In our solution at work, all projects have
<Nullable>disable</Nullable>. In some of the generated interfaces, we receive the warningwarning CS8625: Cannot convert null literal to non-nullable reference type., because the interfaces are generated with#nullable enableand have parameters likestring input = null.I've changed the generator so that these parameters activate the nullable mode and add a
?if it's missing.There were some changes in the tests I didn't expect, e.g. Misc.CustomNameSpace, but I think they're all correct like this.
Note that for 100% correctness, I think we would need to check the semantic model for every method and get the nullable context to decide if a parameter is actually nullable or not.