Add specs for exporting commits as diff or patch

spec/controllers/commit_controller_spec.rb

+require 'spec_helper'
+
+describe CommitController do
+  let(:project) { create(:project) }
+  let(:user)    { create(:user) }
+  let(:commit)  { project.last_commit_for("master") }
+
+  before do
+    sign_in(user)
+
+    project.add_access(user, :read, :admin)
+  end
+
+  describe "#show" do
+    shared_examples "export as" do |format|
+      it "should generally work" do
+        get :show, project_id: project.code, id: commit.id, format: format
+
+        expect(response).to be_success
+      end
+
+      it "should generate it" do
+        Commit.any_instance.should_receive(:"to_#{format}")
+
+        get :show, project_id: project.code, id: commit.id, format: format
+      end
+
+      it "should render it" do
+        get :show, project_id: project.code, id: commit.id, format: format
+
+        expect(response.body).to eq(commit.send(:"to_#{format}"))
+      end
+
+      it "should not escape Html" do
+        Commit.any_instance.stub(:"to_#{format}").and_return('HTML entities &<>" ')
+
+        get :show, project_id: project.code, id: commit.id, format: format
+
+        expect(response.body).to_not include('&amp;')
+        expect(response.body).to_not include('&gt;')
+        expect(response.body).to_not include('&lt;')
+        expect(response.body).to_not include('&quot;')
+      end
+    end
+
+    describe "as diff" do
+      include_examples "export as", :diff
+      let(:format) { :diff }
+
+      it "should really only be a git diff" do
+        get :show, project_id: project.code, id: commit.id, format: format
+
+        expect(response.body).to start_with("diff --git")
+      end
+    end
+
+    describe "as patch" do
+      include_examples "export as", :patch
+      let(:format) { :patch }
+
+      it "should really be a git email patch" do
+        get :show, project_id: project.code, id: commit.id, format: format
+
+        expect(response.body).to start_with("From #{commit.id}")
+      end
+
+      it "should contain a git diff" do
+        get :show, project_id: project.code, id: commit.id, format: format
+
+        expect(response.body).to match(/^diff --git/)
+      end
+    end
+  end
+end