TYPEDSIGNATURES error with @generated functions

This happens whether the function is @generated, or defined with if @generated ... method.

julia> using DocStringExtensions

julia> begin
       """
           $TYPEDSIGNATURES
       example
       """
       @generated function example(x)
           :(return x)
       end
       end
example

help?> example
search: example

ERROR: BoundsError: attempt to access Core.SimpleVector at index [2]
Stacktrace:
  [1] getindex
    @ ./essentials.jl:697 [inlined]
  [2] may_invoke_generator(method::Method, atype::Any, sparams::Core.SimpleVector)
    @ Base ./reflection.jl:1166
  [3] func_for_method_checked
    @ ./reflection.jl:1188 [inlined]
  [4] return_types(f::Any, types::Any; world::UInt64, interp::Core.Compiler.NativeInterpreter)
    @ Base ./reflection.jl:1415
  [5] return_types
    @ ./reflection.jl:1398 [inlined]
  [6] printmethod(buffer::IOBuffer, binding::Base.Docs.Binding, func::Function, method::Method, typesig::Type)
    @ DocStringExtensions ~/.julia/packages/DocStringExtensions/JVu77/src/utilities.jl:363
  [7] format(#unused#::DocStringExtensions.TypedMethodSignatures, buf::IOBuffer, doc::Base.Docs.DocStr)
    @ DocStringExtensions ~/.julia/packages/DocStringExtensions/JVu77/src/abbreviations.jl:398
  [8] formatdoc(buf::IOBuffer, doc::Base.Docs.DocStr, part::DocStringExtensions.TypedMethodSignatures)
    @ DocStringExtensions ~/.julia/packages/DocStringExtensions/JVu77/src/abbreviations.jl:25
  [9] formatdoc(d::Base.Docs.DocStr)
    @ REPL /Applications/Julia-1.9.2.app/Contents/Resources/julia/share/julia/stdlib/v1.9/REPL/src/docview.jl:88
 [10] parsedoc(d::Base.Docs.DocStr)
    @ REPL /Applications/Julia-1.9.2.app/Contents/Resources/julia/share/julia/stdlib/v1.9/REPL/src/docview.jl:96
 [11] map!(f::typeof(Base.Docs.parsedoc), dest::Vector{Any}, A::Vector{Base.Docs.DocStr})
    @ Base ./abstractarray.jl:3254
 [12] mapany(f::Function, A::Vector{Base.Docs.DocStr})
    @ Base ./abstractarray.jl:3263
 [13] doc(binding::Base.Docs.Binding, sig::Type)
    @ REPL /Applications/Julia-1.9.2.app/Contents/Resources/julia/share/julia/stdlib/v1.9/REPL/src/docview.jl:193
 [14] doc(binding::Base.Docs.Binding)
    @ REPL /Applications/Julia-1.9.2.app/Contents/Resources/julia/share/julia/stdlib/v1.9/REPL/src/docview.jl:160
 [15] top-level scope
    @ /Applications/Julia-1.9.2.app/Contents/Resources/julia/share/julia/stdlib/v1.9/REPL/src/docview.jl:481

SIGNATURES is fine:

julia> begin
       """    
           $SIGNATURES
       example
       """
       @generated function example(x)
           :(return x)
       end
       end
example

help?> example
search: example

  example(x)
  

  example

In my real example, this is happening because I have a template which splices $TYPEDSIGNATURES for all methods. I would indeed like to show the type annotation of the generated function if possible.

Reproduce the example with TYPEDSIGNATURES and compare it with SIGNATURES, using the Julia 1.9.2 behavior shown. Start in src/utilities.jl at printmethod and src/abbreviations.jl at TypedMethodSignatures; done means generated functions no longer trigger the BoundsError and their typed signature is handled as requested.