WIP: fix for JuliaLang#11798 [skip ci]

base/docs/Docs.jl

@@ -36,39 +36,48 @@ end
 
 # Function / Method support
 
-function newmethod(defs)
-    keylen = -1
-    key = nothing
-    for def in defs
-        length(def.sig.parameters) > keylen && (keylen = length(def.sig.parameters); key = def)
+function signature(expr::Expr)
+    if isexpr(expr, :call)
+        tvars = typevars(expr)
+        sig = :(Tuple{})
+        for arg in expr.args[2:end]
+            isexpr(arg, :parameters) && continue
+            push!(sig.args, argtype(arg, tvars))
+        end
+        sig
+    else
+        signature(expr.args[1])
     end
-    return key
 end
 
-function newmethod(funcs, f)
-    applicable = Method[]
-    for def in methods(f)
-        (!haskey(funcs, def) || funcs[def] != def.func) && push!(applicable, def)
-    end
-    return newmethod(applicable)
+function argtype(expr::Expr, tvars::Dict)
+    isexpr(expr, :(::))  && return get(tvars, expr.args[2], expr.args[2])
+    isexpr(expr, :(...)) && return :(Vararg{$(argtype(expr.args[1], tvars))})
+    argtype(expr.args[1], tvars)
 end
+argtype(::Symbol, ::Dict) = :Any
 
-def_dict(f) = [def => def.func for def in methods(f)]
+function typevars(expr::Expr)
+    if isexpr(expr, :curly)
+        tvars = Dict{Symbol, Any}()
+        for arg in expr.args[2:end]
+            isa(arg, Symbol) ?
+                tvars[arg] = :(TypeVar($arg, Any)) :
+                tvars[arg.args[1]] = arg
+        end
+        tvars
+    else
+        typevars(expr.args[1])
+    end
+end
+typevars(::Symbol) = Dict{Symbol, Any}()
 
 function trackmethod(def)
     name = uncurly(unblock(def).args[1].args[1])
     f = esc(name)
     quote
-        funcs = nothing
-        if $(isexpr(name, Symbol)) && isdefined($(Expr(:quote, name))) && isgeneric($f)
-            funcs = def_dict($f)
-        end
         $(esc(def))
-        if funcs !== nothing
-            $f, newmethod(funcs, $f)
-        else
-            $f, newmethod(methods($f))
-        end
+        $f, methods($f, $(esc(signature(def))))[1]
     end
 end
 
@@ -315,7 +324,7 @@ Base.DocBootstrap.setexpand!(docm)
 # inject the ones we need there.
 
 eval(Base.DocBootstrap,
-     :(import ..Docs: @init, doc!, doc, newmethod, def_dict, @doc_str))
+     :(import ..Docs: @init, doc!, doc, @doc_str))
 
 # Metametadata