MA0151 false positive

[dmitriy-maksimov-wd]

Version of the Meziantou.Analyzer NuGet package

2.0.216

Rule Identifier

MA0151

Target Framework

net8.0

C# Language version

C# 11

Description

I have IList<> member.
Getting "Member Count does not exist", but the member exists in ICollection (which IList<> derived from).
The recent fix #830 seems to broke it.

Reproduction Steps

Minimal code:

[DebuggerDisplay("{referenceString} ({allStrings.Count})")]
public struct ContainedStrings
{
    private readonly IList<string> allStrings;
    private readonly string referenceString;

    public void Test()
    {
        var allStringsCount = allStrings.Count;
    }
}

Other information

No response

[meziantou]

It should be fixed by 7fd5060. The new version will be available very soon on nuget.org (https://www.nuget.org/packages/Meziantou.Analyzer/2.0.217).

[luispfgarces]

Hi @meziantou,

It seems that it is still raising false positives when the type of a property is a generic type parameter.

Here's my specific scenario:

[DebuggerDisplay("{RightOperand.DataType.ToString(),nq} condition: <{Condition.ToString(),nq}> {Operator} {RightOperand.Value}")]
public class ValueConditionNode<TCondition> : IValueConditionNode<TCondition>
    where TCondition : notnull
{
    private readonly ValueConditionNode valueConditionNode;

    public ValueConditionNode(ValueConditionNode valueConditionNode)
    {
        this.valueConditionNode = valueConditionNode;
    }

    public TCondition Condition => GenericConversions.Convert<TCondition>(valueConditionNode.Condition);

    public LogicalOperators LogicalOperator => LogicalOperators.Eval;

    public Operators Operator => this.valueConditionNode.Operator;

    public IDictionary<string, object> Properties => this.valueConditionNode.Properties;

    public Operand RightOperand => this.valueConditionNode.RightOperand;
}

It raises the diagnostic message:

Member 'ToString' does not exist (https://github.com/meziantou/Meziantou.Analyzer/blob/main/docs/Rules/MA0151.md)

If we remove the ToString() from the Condition, the diagnostic is resolved, but it is still raised if we remove it from the RightOperand.DataType.

Hope this helps with troubleshooting the issue. Thank you for your time!

[meziantou]

Thanks for reporting this! Next time, could you please open a new issue instead of replying to a closed one? It makes it easier for me to keep track of things.

I push new changes (358803c) that should detect the type parameter case, and also special case ToString.
https://www.nuget.org/packages/Meziantou.Analyzer/2.0.218

[luispfgarces]

Will do next time 👍 Thank you for solving this!