public static IDeclaredElement GetDeclaredElement()

in ReSharper.FSharp/src/FSharp/FSharp.Psi/src/Util/FcsSymbolMappingUtil.cs [132:194]
48 lines of code
24 McCabe index (conditional complexity)

    public static IDeclaredElement GetDeclaredElement([CanBeNull] this FSharpSymbol symbol,
      [NotNull] IPsiModule psiModule, [CanBeNull] IFSharpReferenceOwner referenceOwner = null)
    {
      if (symbol == null)
        return null;

      if (symbol is FSharpEntity entity)
      {
        if (entity.IsUnresolved)
          return null;

        if (entity.IsNamespace)
          return GetDeclaredNamespace(entity, psiModule);

        if (entity.IsFSharpExceptionDeclaration && referenceOwner != null)
          return GetFSharpException(entity, psiModule, referenceOwner);

        return GetTypeElement(entity, psiModule);
      }

      if (symbol is FSharpMemberOrFunctionOrValue mfv)
      {
        if (mfv.IsUnresolved) return null;

        return mfv.IsModuleValueOrMember
          ? GetTypeMember(mfv, psiModule)
          : GetLocalValueDeclaredElement(mfv, referenceOwner);
      }

      if (symbol is FSharpUnionCase unionCase)
        return GetDeclaredElement(unionCase, psiModule);

      if (symbol is FSharpField field)
      {
        if (field.IsAnonRecordField && referenceOwner != null)
          return new FSharpAnonRecordFieldProperty(referenceOwner.Reference);

        if (field.IsUnionCaseField && field.DeclaringUnionCase?.Value is { } fieldUnionCase)
        {
          var unionEntity = fieldUnionCase.ReturnType.TypeDefinition;
          var fieldOwnerTypeElement =
            unionEntity.UnionCases.Count > 1 && !unionEntity.IsValueType
              ? GetDeclaredElement(fieldUnionCase, psiModule, true) as ITypeElement
              : GetTypeElement(unionEntity, psiModule);

          return fieldOwnerTypeElement?.EnumerateOwnMembersWithName(field.Name, true).FirstOrDefault();
        }

        if (!field.IsUnresolved && field.DeclaringEntity?.Value is { } fieldEntity)
          return GetTypeElement(fieldEntity, psiModule)?.EnumerateOwnMembersWithName(field.Name, true).FirstOrDefault();
      }

      if (symbol is FSharpActivePatternCase patternCase)
        return GetActivePatternCaseElement(patternCase, psiModule, referenceOwner);

      if (symbol is FSharpGenericParameter genericParameter)
        return GetTypeParameter(genericParameter, referenceOwner);

      if (symbol is FSharpParameter parameter && referenceOwner != null)
        return parameter.GetOwner(referenceOwner.Reference); // todo: map to parameter

      return null;
    }