Improve presenter architecture

Signed-off-by: Rémy Coutable <remy@rymai.me>

4 files changed, 104 insertions, 29 deletions

diff --git a/spec/lib/gitlab/view/presenter/base_spec.rb b/spec/lib/gitlab/view/presenter/base_spec.rb
new file mode 100644
index 00000000000..57b98276622
--- /dev/null
+++ b/spec/lib/gitlab/view/presenter/base_spec.rb
@@ -0,0 +1,38 @@
+require 'spec_helper'
+
+describe Gitlab::View::Presenter::Base do
+  let(:project) { double(:project) }
+  let(:presenter_class) do
+    Struct.new(:subject).include(described_class)
+  end
+
+  subject do
+    presenter_class.new(project)
+  end
+
+  describe '.presents' do
+    it 'exposes #subject with the given keyword' do
+      presenter_class.presents(:foo)
+
+      expect(subject.foo).to eq(project)
+    end
+  end
+
+  describe '#can?' do
+    let(:project) { create(:empty_project) }
+
+    context 'user is not allowed' do
+      it 'returns false' do
+        expect(subject.can?(nil, :read_project)).to be_falsy
+      end
+    end
+
+    context 'user is allowed' do
+      let(:project) { create(:empty_project, :public) }
+
+      it 'returns true' do
+        expect(subject.can?(nil, :read_project)).to be_truthy
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/view/presenter/delegated_spec.rb b/spec/lib/gitlab/view/presenter/delegated_spec.rb
new file mode 100644
index 00000000000..816d6b7c6d4
--- /dev/null
+++ b/spec/lib/gitlab/view/presenter/delegated_spec.rb
@@ -0,0 +1,33 @@
+require 'spec_helper'
+
+describe Gitlab::View::Presenter::Delegated do
+  let(:project) { double(:project, foo: 'bar') }
+  let(:presenter_class) do
+    Class.new(described_class)
+  end
+
+  subject do
+    presenter_class.new(project)
+  end
+
+  it 'includes Gitlab::View::Presenter::Base' do
+    expect(described_class).to include(Gitlab::View::Presenter::Base)
+  end
+
+  describe '#initialize' do
+    subject do
+      presenter_class.new(project, user: 'user', foo: 'bar')
+    end
+
+    it 'takes arbitrary key/values and exposes them' do
+      expect(subject.user).to eq('user')
+      expect(subject.foo).to eq('bar')
+    end
+  end
+
+  describe 'delegation' do
+    it 'does not forward missing methods to subject' do
+      expect(subject.foo).to eq('bar')
+    end
+  end
+end
diff --git a/spec/lib/gitlab/view/presenter/simple_spec.rb b/spec/lib/gitlab/view/presenter/simple_spec.rb
new file mode 100644
index 00000000000..baf074019ec
--- /dev/null
+++ b/spec/lib/gitlab/view/presenter/simple_spec.rb
@@ -0,0 +1,33 @@
+require 'spec_helper'
+
+describe Gitlab::View::Presenter::Simple do
+  let(:project) { double(:project) }
+  let(:presenter_class) do
+    Class.new(described_class)
+  end
+
+  subject do
+    presenter_class.new(project)
+  end
+
+  it 'includes Gitlab::View::Presenter::Base' do
+    expect(described_class).to include(Gitlab::View::Presenter::Base)
+  end
+
+  describe '#initialize' do
+    subject do
+      presenter_class.new(project, user: 'user', foo: 'bar')
+    end
+
+    it 'takes arbitrary key/values and exposes them' do
+      expect(subject.user).to eq('user')
+      expect(subject.foo).to eq('bar')
+    end
+  end
+
+  describe 'delegation' do
+    it 'does not forward missing methods to subject' do
+      expect { subject.foo }.to raise_error(NoMethodError)
+    end
+  end
+end
diff --git a/spec/lib/gitlab/view/presenter_spec.rb b/spec/lib/gitlab/view/presenter_spec.rb
deleted file mode 100644
index 0880fbe5d77..00000000000
--- a/spec/lib/gitlab/view/presenter_spec.rb
+++ /dev/null
@@ -1,29 +0,0 @@
-require 'spec_helper'
-
-describe Gitlab::View::Presenter do
-  let(:project) { double(:project, bar: 'baz!') }
-  let(:presenter) do
-    base_presenter = described_class
-
-    Class.new do
-      include base_presenter
-
-      presents :foo
-    end
-  end
-  subject do
-    presenter.new.with_subject(project)
-  end
-
-  describe '#initialize' do
-    it 'takes an object accessible via a reader' do
-      expect(subject.foo).to eq(project)
-    end
-  end
-
-  describe 'common helpers' do
-    it 'responds to #can?' do
-      expect(subject).to respond_to(:can?)
-    end
-  end
-end