Add feature test for running a command

spec/features/command_spec.rb

@@ -0,0 +1,269 @@
+RSpec.describe "Running a command", :with_gem do
+  include_context :kangaru_initialised
+
+  describe "calling SomeGem.run! directly" do
+    subject(:run_command!) { SomeGem.run!(argv) }
+
+    let(:target) do
+      Module.new { def self.do_something = nil }
+    end
+
+    before do
+      stub_const "Target", target
+
+      allow(Target).to receive(:do_something)
+    end
+
+    shared_examples :unsuccessful_command do
+      it "does not call the target" do
+        run_command!
+      rescue
+        expect(Target).not_to have_received(:do_something)
+      end
+    end
+
+    shared_examples :handles_undefined_controller do |**options|
+      include_examples :unsuccessful_command
+
+      it "raises an UndefinedControllerError" do
+        expect { run_command! }.to raise_error(
+          Kangaru::Router::UndefinedControllerError,
+          "#{options[:controller]} is not defined in SomeGem"
+        )
+      end
+    end
+
+    shared_examples :handles_undefined_action do |**options|
+      it "raises an UndefinedActionError" do
+        expect { run_command! }.to raise_error(
+          Kangaru::Router::UndefinedActionError,
+          "#{options[:action]} is not defined by #{options[:controller]}"
+        )
+      end
+    end
+
+    shared_examples :successful_command do
+      it "does not raise any errors" do
+        expect { run_command! }.not_to raise_error
+      end
+
+      it "runs the default action" do
+        run_command!
+        expect(Target).to have_received(:do_something).once
+      end
+    end
+
+    context "when no arguments are given" do
+      let(:argv) { [] }
+
+      context "and default controller is not defined" do
+        before { gem.load! }
+
+        include_examples :handles_undefined_controller,
+                         controller: "DefaultController"
+      end
+
+      context "and default controller is defined" do
+        before do
+          gem.gem_file("default_controller").write(controller)
+          gem.load!
+        end
+
+        context "and default action is not defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                class DefaultController < Kangaru::Controller
+                  def foobar
+                    Target.do_something
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :handles_undefined_action,
+                           controller: "DefaultController",
+                           action: "default"
+        end
+
+        context "and default action is defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                class DefaultController < Kangaru::Controller
+                  def default
+                    Target.do_something
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :successful_command
+        end
+      end
+    end
+
+    context "when one argument is given" do
+      let(:argv) { %w[foobar] }
+
+      context "and specified controller is not defined" do
+        before { gem.load! }
+
+        include_examples :handles_undefined_controller,
+                         controller: "FoobarController"
+      end
+
+      context "and specified controller is defined" do
+        before do
+          gem.gem_file("foobar_controller").write(controller)
+          gem.load!
+        end
+
+        context "and default action is not defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                class FoobarController < Kangaru::Controller
+                  def foobar
+                    Target.do_something
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :handles_undefined_action,
+                           controller: "FoobarController",
+                           action: "default"
+        end
+
+        context "and default action is defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                class FoobarController < Kangaru::Controller
+                  def default
+                    Target.do_something
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :successful_command
+        end
+      end
+    end
+
+    context "when two arguments are given" do
+      let(:argv) { %w[foobar some_action] }
+
+      context "and specified controller is not defined" do
+        before { gem.load! }
+
+        include_examples :handles_undefined_controller,
+                         controller: "FoobarController"
+      end
+
+      context "and specified controller is defined" do
+        before do
+          gem.gem_file("foobar_controller").write(controller)
+          gem.load!
+        end
+
+        context "and specified action is not defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                class FoobarController < Kangaru::Controller
+                  def foobar
+                    Target.do_something
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :handles_undefined_action,
+                           controller: "FoobarController",
+                           action: "some_action"
+        end
+
+        context "and specified action is defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                class FoobarController < Kangaru::Controller
+                  def some_action
+                    Target.do_something
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :successful_command
+        end
+      end
+    end
+
+    context "when three arguments are given" do
+      let(:argv) { %w[namespace foobar some_action] }
+
+      context "and specified nested controller is not defined" do
+        before { gem.load! }
+
+        include_examples :handles_undefined_controller,
+                         controller: "Namespace::FoobarController"
+      end
+
+      context "and specified nested controller is defined" do
+        before do
+          gem.gem_dir("namespace").mkdir
+          gem.gem_file("namespace/foobar_controller").write(controller)
+          gem.load!
+        end
+
+        context "and specified action is not defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                module Namespace
+                  class FoobarController < Kangaru::Controller
+                    def foobar
+                      Target.do_something
+                    end
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :handles_undefined_action,
+                           controller: "Namespace::FoobarController",
+                           action: "some_action"
+        end
+
+        context "and specified action is defined" do
+          let(:controller) do
+            <<~RUBY
+              module SomeGem
+                module Namespace
+                  class FoobarController < Kangaru::Controller
+                    def some_action
+                      Target.do_something
+                    end
+                  end
+                end
+              end
+            RUBY
+          end
+
+          include_examples :successful_command
+        end
+      end
+    end
+  end
+end