[Bug Report] `include` directive silently fails when using absolute paths

[tsx8]

Checks

• I have searched the existing issues
• I have read the documentation
• Is it your first time sumbitting an issue

Current Behavior

When using an absolute path in the include directive, the included file is silently ignored without any error or warning message.

For example, with this configuration:

include {
  '/etc/dae/sub.dae'
}

The file sub.dae is not loaded, but dae produces no error of it, but errors about missing definitions in the included file.

Expected Behavior

Abosulte paths in include should work correctly, or at least show a clear warning in docs like "absolute paths not supported in include directive".

I expected the fix because I am configuring my NixOS and encrypting subscription information, which is not appropriate to use relative path for the main config. (Probably I am doing in the wrong way.)

Steps to Reproduce

1. Create a main config file config.dae:

   include {
       '/etc/dae/sub.dae'
   }
   
   global {
       tproxy_port: 12345
   }
   

2. Create a sub config file sub.dae:

   group {
       mygroup {
           # some proxies
       }
   }
   

3. Set proper permissions and then validate or run.
4. Observe that mygroup is not loaded.

Environment

• Dae version (use dae --version): unstable-20251103.r826.7e67e31
• OS (e.g cat /etc/os-release): Ubuntu 24.04.3 LTS
• Kernel (e.g. uname -a): 6.6.87.2-microsoft-standard-WSL2
• Others: NA

Note that the problem is found during my NisOS configuration, so probably it's not a WSL problem.

Anything else?

In config_merger.go the dfsMerge function processes include paths like this:

case *config_parser.Param:
    nextEntry := v.String(true, false)
    patterEntries = append(patterEntries, filepath.Join(m.entryDir, nextEntry))

for an absolute path /etc/dae/sub.dae, it will just result in /etc/dae/etc/dae/sub.dae. And after that, the filepath.Glob(pattern) will not throw any errors or warnings. So just consider check if the path is absolute before joining.

[dae-prow]

Thanks for opening this issue!

[MaurUppi]

Agreed! dae run validate -c /path/to/config.dae did NOT report this issue.

Even example.dae had mentioned /etc/dae/relative/path/to/mysub.sub
BUT it's easy to make a mistake.

dae/example.dae

Lines 131 to 136 in 7e67e31

	subscription {
	# Add your subscription links here.
	my_sub: 'https://www.example.com/subscription/link'
	another_sub: 'https://example.com/another_sub'
	'https://example.com/no_tag_link'
	'file://relative/path/to/mysub.sub' # Put subscription content in /etc/dae/relative/path/to/mysub.sub

[tsx8]

Agreed! dae run validate -c /path/to/config.dae did NOT report this issue.

Even example.dae had mentioned /etc/dae/relative/path/to/mysub.sub BUT it's easy to make a mistake.

dae/example.dae

Lines 131 to 136 in 7e67e31

subscription {
# Add your subscription links here.
my_sub: 'https://www.example.com/subscription/link'
another_sub: 'https://example.com/another_sub'
'https://example.com/no_tag_link'
'file://relative/path/to/mysub.sub' # Put subscription content in /etc/dae/relative/path/to/mysub.sub

I think the validate funtion does not run very well, still need actually running to verify a lot cases :(