Add-SPSolution and Install-SPSolution is working even without installing it's dependencies

Question

I have one farm solution that have two activation dependencies defined as:

<ActivationDependencies>
    <ActivationDependency SolutionId="{4400849B-2E03-4030-95DB-D98B1790EAD9}" SolutionName="Dependency1.wsp" />
    <ActivationDependency SolutionId="{268a5397-f984-43d3-8234-e835613b7e21}" SolutionName="Dependency2.wsp" />
  </ActivationDependencies>

I tough that those dependencies would not allow me to Add and Install the Solution without those solutions were added. But it was added without problems, and even I didn't use force.

I even check by using the command Get-SPSolution if those solutions Dependency1 and Dependency2 were there, but they aren't.

For add the solution I used the command:

Add-SPSolution -LiteralPath {path in here}

And to deploy the package I used:

Install-SPSolution -Identity MainPackage.wsp -GCDeployment -AllWebApplications

When I get the validation of the Activation dependency ? Is not when I try to install the solution ? Because the problem is that when I try to activate some features, there are some missing packages and it just shows: "An error has occurred"

Note: The two dependencies have no Features, but only Assemblies, so I can't make a dependency between features.

Answer 1

Activation dependencies are applicable only when you are activating the feature (as the name suggests).

You could refer this article, which says the following about dependencies in the same solution,

You can add other Features in your solution as dependencies. This way, you can make sure that required Features are installed and activated before your feature is installed.

and, regarding custom dependencies, (which apply to your scenario) i.e. when the feature dependencies are in a different solution:

You can add Features that are already deployed on a SharePoint server as a dependency. This way, the SharePoint activation process checks to make sure that all dependent Features are activated before your Feature is installed.

Essentially, you could install solutions in any order, however at the time of activation for a particular feature, you must have all of its dependencies activated.