lookup path using moduleroot & pathof

base/loading.jl

@@ -1268,13 +1268,14 @@ function _include_from_serialized(pkg::PkgId, path::String, ocachepath::Union{No
 end
 
 function extension_parent(M::Module)
-    @show _pkgdir = pkgdir(M)
-    _pkgdir === nothing && return nothing
-    pkgdir_parts = splitpath(_pkgdir)
+    rootmodule = moduleroot(M)
+    src_path = pathof(rootmodule)
+    src_path === nothing && return nothing
+    pkgdir_parts = splitpath(src_path)
     ext_pos = findlast(==("ext"), pkgdir_parts)
-    if ext_pos !== nothing && ext_pos >= length(pkgdir_parts) - 1
-        @show parent_package_root = joinpath(pkgdir_parts[1:ext_pos-1]...)
-        @show parent_package_project_file = locate_project_file(parent_package_root)
+    if ext_pos !== nothing && ext_pos >= length(pkgdir_parts) - 2
+        parent_package_root = joinpath(pkgdir_parts[1:ext_pos-1]...)
+        parent_package_project_file = locate_project_file(parent_package_root)
         if parent_package_project_file isa String
             d = parsed_toml(parent_package_project_file)
             name = get(d, "name", nothing)