Add none? method to Resolvable class

library/packages/src/lib/y2packager/resolvable.rb

@@ -81,6 +81,15 @@ def self.any?(params)
       Yast::Pkg.AnyResolvable(params)
     end
 
+    # Return true when there is no resolvable matching the requested parameters or false
+    # otherwise.
+    #
+    # @param params [Hash<Symbol,Object>] The requested attributes
+    # @return [Boolean] `true` if no matching resolvable is found, `false` otherwise.
+    def self.none?(params)
+      !any?(params)
+    end
+
     #
     # Constructor, initialize the object from a pkg-bindings resolvable hash.
     #

library/packages/test/y2packager/resolvable_test.rb

@@ -141,6 +141,25 @@ def accept_unsigned_file(file, _repo)
     end
   end
 
+  describe ".none?" do
+    it "returns true if no package is found" do
+      expect(Y2Packager::Resolvable.none?(kind: :package, name: "not existing")).to be true
+    end
+
+    it "returns true if no product is found" do
+      expect(Y2Packager::Resolvable.none?(kind: :product, name: "openSUSE")).to be true
+    end
+
+    it "returns false if a package with name is found" do
+      # use some noarch package here, the testing data covers only the x86_64 arch
+      expect(Y2Packager::Resolvable.none?(kind: :package, name: "yast2-add-on")).to be false
+    end
+
+    it "returns false if a package is found" do
+      expect(Y2Packager::Resolvable.none?(kind: :package)).to be false
+    end
+  end
+
   describe "#vendor" do
     it "lazy loads the missing attributes" do
       # use some noarch package here, the testing data covers only the x86_64 arch