typedef not found when 'include' used in submodule

[preetjuniper]

I see the following error when referencing a typedef in a submodule where another submodule under the same parent module is explicitly included.

application/application/system/level - typedef log-level not found

When the submodule is not explicitly included, there's no error. Using a prefix makes no difference. I tried to print out which 'node's (not sure what the right terminology is) are crawled to find the typedef in findTypedef in freeconf/yang/meta/compile.go, I see different nodes are traversed with and without the include:

// with "include some-types;"
>> rm -f testfreeconf && go build && ./testfreeconf
searching ident: level               // just fmt.Printf("searching ident: %v\n", p.Ident())
searching ident: log-params
searching ident: system
panic: application/application/system/level - typedef log-level not found

goroutine 1 [running]:
main.main()
	/n/dev/scratch/freeconf/main.go:26 +0x8d

// without "include some-types;"
>> rm -f testfreeconf && go build && ./testfreeconf
searching ident: level
searching ident: log-params
searching ident: application

In RFC 7590 the include is optional, but I believe its mandatory in 6020. From section 5.1:

o For a submodule to reference definitions in a second submodule of
the same module, the first submodule MUST include the second
submodule.

Yang files:

module application {
    namespace "urn:application";
    prefix "app";

    include some-types;
    include system;

    organization "";
    contact "";
    description "";
    revision 2024-01-01 {
        description "";
        reference "";
    }

    container application {
        uses system;
    }
}

submodule some-types {
    belongs-to application {
        prefix app;
    }

    organization "";
    contact "";
    description "";
    revision 2024-01-01 {
        description "";
        reference "";
    }

    typedef log-level {
        type enumeration {
            enum debug;
            enum info;
            enum warn;
            enum error;
        }
    }
    grouping log-params {
        leaf filename {
            type string;
        }
        leaf filesize {
            type int32;
        }
        leaf level {
            type log-level;
        }
    }
}

submodule system {
    belongs-to application {
        prefix app;
    }

    // This include statement causes an error
    include some-types;

    organization "";
    contact "";
    description "";
    revision 2024-01-01 {
        description "";
        reference "";
    }

    grouping system {
        container system {
            uses log-params;
        }
    }
}

Attempt to load the modules

package main

import (
	"github.com/freeconf/yang/parser"
	"github.com/freeconf/yang/source"
	"github.com/freeconf/yang/fc"
)

func main() {
	// enable debug logging
	fc.DebugLog(true)

	// load model
	_, errLdMdl := parser.LoadModule(source.Dir("appyang"), "application")
	if errLdMdl != nil {
		panic(errLdMdl.Error())
	}
}