MarkdownAST attempted to iterate a `Markdown.Paragraph`

[tecosaur]

Hi, in trying to upgrade to Documenter 1.0 I've hit this issue (with DataToolkitBase).

ERROR: LoadError: MethodError: no method matching iterate(::Markdown.Paragraph)

Closest candidates are:
  iterate(::RegexMatch, Any...)
   @ Base regex.jl:284
  iterate(::ExponentialBackOff)
   @ Base error.jl:260
  iterate(::ExponentialBackOff, ::Any)
   @ Base error.jl:260
  ...

Stacktrace:
  [1] _convert(nodefn::MarkdownAST.NodeFn{Nothing}, c::MarkdownAST.Item, child_convert_fn::typeof(MarkdownAST._convert_block), md_children::Markdown.Paragraph)
    @ MarkdownAST ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:33
  [2] _convert_block(nodefn::MarkdownAST.NodeFn{Nothing}, b::Markdown.List)
    @ MarkdownAST ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:65
  [3] _convert(nodefn::MarkdownAST.NodeFn{Nothing}, c::MarkdownAST.Item, child_convert_fn::typeof(MarkdownAST._convert_block), md_children::Vector{Any})
    @ MarkdownAST ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:34
  [4] _convert_block(nodefn::MarkdownAST.NodeFn{Nothing}, b::Markdown.List)
    @ MarkdownAST ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:65
  [5] _convert(nodefn::MarkdownAST.NodeFn{Nothing}, c::MarkdownAST.Document, child_convert_fn::typeof(MarkdownAST._convert_block), md_children::Vector{Any})
    @ MarkdownAST ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:34
  [6] convert (repeats 2 times)
    @ Documenter ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:23 [inlined]
  [7] convert
    @ Documenter ~/.julia/packages/MarkdownAST/CZtZT/src/stdlib/fromstdlib.jl:21 [inlined]
  [8] (::Documenter.var"#49#50"{MarkdownAST.Node{Nothing}, Documenter.Page, Documenter.Document, LineNumberNode, Module, MarkdownAST.CodeBlock})()
    @ Documenter ~/.julia/packages/Documenter/Meee1/src/expander_pipeline.jl:630
  [9] cd(f::Documenter.var"#49#50"{MarkdownAST.Node{Nothing}, Documenter.Page, Documenter.Document, LineNumberNode, Module, MarkdownAST.CodeBlock}, dir::String)
    @ Base.Filesystem ./file.jl:112
 [10] runner(::Type{Documenter.Expanders.EvalBlocks}, node::MarkdownAST.Node{Nothing}, page::Documenter.Page, doc::Documenter.Document)
    @ Documenter ~/.julia/packages/Documenter/Meee1/src/expander_pipeline.jl:610
 [...]
 [20] top-level scope
    @ ~/.julia/dev/DataToolkitBase/docs/make.jl:19
in expression starting at /home/tec/.julia/dev/DataToolkitBase/docs/make.jl:19

[mortenpi]

It looks like you have an invalid Markdown stdlib AST. Do you have an MWE? I suspect it did not come from the parser..

[tecosaur]

I'm not completely sure which bit of the docs it's coming from, but the obvious candidate is this @eval block here: https://github.com/tecosaur/DataToolkitBase.jl/blob/main/docs/src/advising.org#index-of-advised-calls

[mortenpi]

I'd say your best bet would be to add some debug prints into MarkdownAST and see what AST it's converting when it crashes. From the stacktrace it looks like there's a list that is not wrapped enough times in vectors.