Recommendations with virtual dependencies don't appear in GUI

[HebaruSan]

Background

CKAN Version:
1.22.6 and current HEAD

KSP Version:
1.3.1

Operating System:
Windows 7, Windows 10

Have you made any manual changes to your GameData folder (i.e., not via CKAN)?
No

Problem

What steps did you take in CKAN?

1. Create a .netkan file with Scatterer as a recommendation
2. Run it through netkan.exe
3. In GUI, File → Install from .ckan...
4. Select the .ckan file generated in step 2

What did you expect to happen?
Scatterer should appear in the list of recommended mods to install

What happened instead?
Other recommendations appear, but Scatterer doesn't.

Screenshots:

CKAN error codes (if applicable):

I instrumented the code with various exception handlers in Main.GetShowableMods:

Exception thrown looking up Scatterer: Exception of type 'CKAN.InconsistentKraken' was thrown.
   at CKAN.SanityChecker.EnforceConsistency(IEnumerable`1 modules, IEnumerable`1 dlls)
   at CKAN.RelationshipResolver.AddModulesToInstall(IEnumerable`1 modules)
   at CKAN.RelationshipResolver..ctor(IEnumerable`1 modules, RelationshipResolverOptions options, IRegistryQuerier registry, KspVersionCriteria kspversion)
   at CKAN.RelationshipResolver..ctor(IEnumerable`1 module_names, RelationshipResolverOptions options, IRegistryQuerier registry, KspVersionCriteria kspversion)
   at CKAN.Main.GetShowableMods(Dictionary`2 mods)

Kraken for Scatterer: The following inconsistencies were found:
Scatterer has an unmet dependency: Scatterer-sunflare is not installed
 * Scatterer has an unmet dependency: Scatterer-config is not installed

That function turns off handling of virtual mods and turns on consistency checks:

CKAN/GUI/MainInstall.cs

Lines 410 to 417 in dfd03d7

	var opts = new RelationshipResolverOptions
	{
	with_all_suggests = false,
	with_recommends = false,
	with_suggests = false,
	without_enforce_consistency = false,
	without_toomanyprovides_kraken = true
	};

Then when it does a consistency check, it discovers that Scatterer has unsatisfied dependencies, since they're virtual, and the InconsistentKraken makes it skip to the next recommendation:

CKAN/GUI/MainInstall.cs

Lines 423 to 438 in dfd03d7

	try
	{
	var resolver = new RelationshipResolver(new List<string> { pair.Key }, opts,
	RegistryManager.Instance(manager.CurrentInstance).registry, CurrentInstance.VersionCriteria());
	if (!resolver.ModList().Any())
	{
	continue;
	}
	module = RegistryManager.Instance(manager.CurrentInstance)
	.registry.LatestAvailable(pair.Key, CurrentInstance.VersionCriteria());
	}
	catch
	{
	continue;
	}

Scatterer's metadata isn't actually invalid, so it should be possible for another mod to recommend it.

Thanks to @Sigma88 for reporting this via forum PM.

[Sigma88]

thanks @HebaruSan for opening this 👍

[HebaruSan]

New script to query relationships found one example of this in live data:

• ExtrasolarPlanetsBeyondKerbol-stock recommends Scatterer

Confirmed that installing that mod in GUI doesn't pull in Scatterer in the recommendation list.