Multiple DHE Assemblies

When multiple DHE assemblies exist, the decision to call LoadOriginalDifferentialHybridAssembly or LoadDifferentialHybridAssemblyUnchecked for loading depends on whether each assembly has changed. However, there are some additional restrictions.

Restrictions

Loading multiple DHE assemblies must meet the following conditions:

• Assemblies must be loaded in the order of their dependencies.
• If a DHE assembly is loaded using LoadDifferentialHybridAssemblyUnchecked, then all DHE assemblies that directly or indirectly depend on it must also be loaded using LoadDifferentialHybridAssemblyUnchecked, even if those assemblies have not changed.

Transitivity of LoadDifferentialHybridAssemblyUnchecked

Due to some complex implementation reasons, if a DHE assembly is loaded using LoadDifferentialHybridAssemblyUnchecked, then all DHE assemblies that directly or indirectly depend on it must also be loaded using LoadDifferentialHybridAssemblyUnchecked.

For example, suppose Assembly B references Assembly A:

Assembly	Loading Method
A	LoadOriginalDifferentialHybridAssembly
B	LoadOriginalDifferentialHybridAssembly or LoadDifferentialHybridAssemblyUnchecked
A (Changed)	LoadDifferentialHybridAssemblyUnchecked
B (Must Use)	LoadDifferentialHybridAssemblyUnchecked

If Assembly A changes, then even if Assembly B has not been modified, it must still be loaded using LoadDifferentialHybridAssemblyUnchecked.

Computing DHE Assemblies That Need to Be Loaded Using LoadDifferentialHybridAssemblyUnchecked

Suppose you have multiple DHE assemblies A1 to An. If only A1 and A3 change in a certain update, it is not enough to load just these two assemblies using LoadDifferentialHybridAssemblyUnchecked. All assemblies that directly or indirectly depend on A1 and A3 must also be loaded using LoadDifferentialHybridAssemblyUnchecked. When the number of assemblies is small, this is manageable manually, but when dealing with a large number of assemblies, it is easy to make mistakes.

Starting from version v7.5.0, a new function HybridCLR.Editor.DHE.BuildUtils::ComputeAssembliesLoadedByLoadDifferentialHybridAssembly has been added to compute the final list of DHE assemblies that need to be loaded using LoadDifferentialHybridAssemblyUnchecked based on the list of known changed DHE assemblies.

Example Code

BuildTarget target = EditorUserBuildSettings.activeBuildTarget;
HybridCLRSettings settings = HybridCLRSettings.Instance;
string[] differentialHybridAssemblyList = settings.differentialHybridAssemblies;

string currentAssemblyDir = SettingsUtil.GetHotUpdateDllsOutputDirByTarget(target);

var assList = BuildUtils.ComputeAssembliesLoadedByLoadDifferentialHybridAssembly(new string[] { "MyCode" }, differentialHybridAssemblyList, currentAssemblyDir);
foreach (var ass in assList)
{
    Debug.Log($"assembly:{ass}");
}