fix #22798, displaying generated function signatures without `.source…

…` defined

base/methodshow.jl

@@ -51,9 +51,9 @@ function arg_decl_parts(m::Method)
  end
  file = m.file
  line = m.line
- if isdefined(m, :source)
+ if isdefined(m, :source) || isdefined(m, :generator)
  argnames = Vector{Any}(m.nargs)
- ccall(:jl_fill_argnames, Void, (Any, Any), m.source, argnames)
+ ccall(:jl_fill_argnames, Void, (Any, Any), isdefined(m, :source) ? m.source : m.generator.inferred, argnames)
  show_env = ImmutableDict{Symbol, Any}()
  for t in tv
  show_env = ImmutableDict(show_env, :unionall_env => t)
@@ -71,7 +71,7 @@ function kwarg_decl(m::Method, kwtype::DataType)
  kwli = ccall(:jl_methtable_lookup, Any, (Any, Any, UInt), kwtype.name.mt, sig, typemax(UInt))
  if kwli !== nothing
  kwli = kwli::Method
- src = uncompressed_ast(kwli, kwli.source)
+ src = uncompressed_ast(kwli)
  kws = filter(x -> !('#' in string(x)), src.slotnames[(kwli.nargs + 1):end])
  # ensure the kwarg... is always printed last. The order of the arguments are not
  # necessarily the same as defined in the function

test/replutil.jl

@@ -575,3 +575,10 @@ end
  @test !contains(str, "The applicable method may be too new")
  end
 end
+
+# issue #22798
+@generated f22798(x::Integer, y) = :x
+let buf = IOBuffer()
+ show(buf, methods(f22798))
+ @test contains(String(take!(buf)), "f22798(x::Integer, y)")
+end