Merge branch '4273-slash-commands' into 'master'

Support slash commands in issues / MR description & comments

See merge request !5021

20 files changed, 1715 insertions, 16 deletions

diff --git a/spec/features/issues/user_uses_slash_commands_spec.rb b/spec/features/issues/user_uses_slash_commands_spec.rb
new file mode 100644
index 00000000000..2883e392694
--- /dev/null
+++ b/spec/features/issues/user_uses_slash_commands_spec.rb
@@ -0,0 +1,58 @@
+require 'rails_helper'
+
+feature 'Issues > User uses slash commands', feature: true, js: true do
+  include WaitForAjax
+
+  it_behaves_like 'issuable record that supports slash commands in its description and notes', :issue do
+    let(:issuable) { create(:issue, project: project) }
+  end
+
+  describe 'issue-only commands' do
+    let(:user) { create(:user) }
+    let(:project) { create(:project, :public) }
+
+    before do
+      project.team << [user, :master]
+      login_with(user)
+      visit namespace_project_issue_path(project.namespace, project, issue)
+    end
+
+    describe 'adding a due date from note' do
+      let(:issue) { create(:issue, project: project) }
+
+      it 'does not create a note, and sets the due date accordingly' do
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/due 2016-08-28"
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/due 2016-08-28'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        issue.reload
+
+        expect(issue.due_date).to eq Date.new(2016, 8, 28)
+      end
+    end
+
+    describe 'removing a due date from note' do
+      let(:issue) { create(:issue, project: project, due_date: Date.new(2016, 8, 28)) }
+
+      it 'does not create a note, and removes the due date accordingly' do
+        expect(issue.due_date).to eq Date.new(2016, 8, 28)
+
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/remove_due_date"
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/remove_due_date'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        issue.reload
+
+        expect(issue.due_date).to be_nil
+      end
+    end
+  end
+end
diff --git a/spec/features/merge_requests/user_uses_slash_commands_spec.rb b/spec/features/merge_requests/user_uses_slash_commands_spec.rb
new file mode 100644
index 00000000000..d9ef0d18074
--- /dev/null
+++ b/spec/features/merge_requests/user_uses_slash_commands_spec.rb
@@ -0,0 +1,32 @@
+require 'rails_helper'
+
+feature 'Merge Requests > User uses slash commands', feature: true, js: true do
+  include WaitForAjax
+
+  let(:user) { create(:user) }
+  let(:project) { create(:project, :public) }
+  let(:merge_request) { create(:merge_request, source_project: project) }
+  let!(:milestone) { create(:milestone, project: project, title: 'ASAP') }
+
+  it_behaves_like 'issuable record that supports slash commands in its description and notes', :merge_request do
+    let(:issuable) { create(:merge_request, source_project: project) }
+    let(:new_url_opts) { { merge_request: { source_branch: 'feature' } } }
+  end
+
+  describe 'adding a due date from note' do
+    before do
+      project.team << [user, :master]
+      login_with(user)
+      visit namespace_project_merge_request_path(project.namespace, project, merge_request)
+    end
+
+    it 'does not recognize the command nor create a note' do
+      page.within('.js-main-target-form') do
+        fill_in 'note[note]', with: "/due 2016-08-28"
+        click_button 'Comment'
+      end
+
+      expect(page).not_to have_content '/due 2016-08-28'
+    end
+  end
+end
diff --git a/spec/fixtures/emails/commands_in_reply.eml b/spec/fixtures/emails/commands_in_reply.eml
new file mode 100644
index 00000000000..06bf60ab734
--- /dev/null
+++ b/spec/fixtures/emails/commands_in_reply.eml
@@ -0,0 +1,43 @@
+Return-Path: <jake@adventuretime.ooo>
+Received: from iceking.adventuretime.ooo ([unix socket]) by iceking (Cyrus v2.2.13-Debian-2.2.13-19+squeeze3) with LMTPA; Thu, 13 Jun 2013 17:03:50 -0400
+Received: from mail-ie0-x234.google.com (mail-ie0-x234.google.com [IPv6:2607:f8b0:4001:c03::234]) by iceking.adventuretime.ooo (8.14.3/8.14.3/Debian-9.4) with ESMTP id r5DL3nFJ016967 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for <reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo>; Thu, 13 Jun 2013 17:03:50 -0400
+Received: by mail-ie0-f180.google.com with SMTP id f4so21977375iea.25 for <reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo>; Thu, 13 Jun 2013 14:03:48 -0700
+Received: by 10.0.0.1 with HTTP; Thu, 13 Jun 2013 14:03:48 -0700
+Date: Thu, 13 Jun 2013 17:03:48 -0400
+From: Jake the Dog <jake@adventuretime.ooo>
+To: reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo
+Message-ID: <CADkmRc+rNGAGGbV2iE5p918UVy4UyJqVcXRO2=otppgzduJSg@mail.gmail.com>
+In-Reply-To: <issue_1@localhost>
+References: <issue_1@localhost> <reply-59d8df8370b7e95c5a49fbf86aeb2c93@localhost>
+Subject: re: [Discourse Meta] eviltrout posted in 'Adventure Time Sux'
+Mime-Version: 1.0
+Content-Type: text/plain;
+ charset=ISO-8859-1
+Content-Transfer-Encoding: 7bit
+X-Sieve: CMU Sieve 2.2
+X-Received: by 10.0.0.1 with SMTP id n7mr11234144ipb.85.1371157428600; Thu,
+ 13 Jun 2013 14:03:48 -0700 (PDT)
+X-Scanned-By: MIMEDefang 2.69 on IPv6:2001:470:1d:165::1
+
+Cool!
+
+/close
+/todo
+/due tomorrow
+
+
+On Sun, Jun 9, 2013 at 1:39 PM, eviltrout via Discourse Meta
+<reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo> wrote:
+>
+>
+>
+> eviltrout posted in 'Adventure Time Sux' on Discourse Meta:
+>
+> ---
+> hey guys everyone knows adventure time sucks!
+>
+> ---
+> Please visit this link to respond: http://localhost:3000/t/adventure-time-sux/1234/3
+>
+> To unsubscribe from these emails, visit your [user preferences](http://localhost:3000/user_preferences).
+>
diff --git a/spec/fixtures/emails/commands_only_reply.eml b/spec/fixtures/emails/commands_only_reply.eml
new file mode 100644
index 00000000000..aed64224b06
--- /dev/null
+++ b/spec/fixtures/emails/commands_only_reply.eml
@@ -0,0 +1,41 @@
+Return-Path: <jake@adventuretime.ooo>
+Received: from iceking.adventuretime.ooo ([unix socket]) by iceking (Cyrus v2.2.13-Debian-2.2.13-19+squeeze3) with LMTPA; Thu, 13 Jun 2013 17:03:50 -0400
+Received: from mail-ie0-x234.google.com (mail-ie0-x234.google.com [IPv6:2607:f8b0:4001:c03::234]) by iceking.adventuretime.ooo (8.14.3/8.14.3/Debian-9.4) with ESMTP id r5DL3nFJ016967 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for <reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo>; Thu, 13 Jun 2013 17:03:50 -0400
+Received: by mail-ie0-f180.google.com with SMTP id f4so21977375iea.25 for <reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo>; Thu, 13 Jun 2013 14:03:48 -0700
+Received: by 10.0.0.1 with HTTP; Thu, 13 Jun 2013 14:03:48 -0700
+Date: Thu, 13 Jun 2013 17:03:48 -0400
+From: Jake the Dog <jake@adventuretime.ooo>
+To: reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo
+Message-ID: <CADkmRc+rNGAGGbV2iE5p918UVy4UyJqVcXRO2=otppgzduJSg@mail.gmail.com>
+In-Reply-To: <issue_1@localhost>
+References: <issue_1@localhost> <reply-59d8df8370b7e95c5a49fbf86aeb2c93@localhost>
+Subject: re: [Discourse Meta] eviltrout posted in 'Adventure Time Sux'
+Mime-Version: 1.0
+Content-Type: text/plain;
+ charset=ISO-8859-1
+Content-Transfer-Encoding: 7bit
+X-Sieve: CMU Sieve 2.2
+X-Received: by 10.0.0.1 with SMTP id n7mr11234144ipb.85.1371157428600; Thu,
+ 13 Jun 2013 14:03:48 -0700 (PDT)
+X-Scanned-By: MIMEDefang 2.69 on IPv6:2001:470:1d:165::1
+
+/close
+/todo
+/due tomorrow
+
+
+On Sun, Jun 9, 2013 at 1:39 PM, eviltrout via Discourse Meta
+<reply+59d8df8370b7e95c5a49fbf86aeb2c93@appmail.adventuretime.ooo> wrote:
+>
+>
+>
+> eviltrout posted in 'Adventure Time Sux' on Discourse Meta:
+>
+> ---
+> hey guys everyone knows adventure time sucks!
+>
+> ---
+> Please visit this link to respond: http://localhost:3000/t/adventure-time-sux/1234/3
+>
+> To unsubscribe from these emails, visit your [user preferences](http://localhost:3000/user_preferences).
+>
diff --git a/spec/lib/gitlab/email/handler/create_note_handler_spec.rb b/spec/lib/gitlab/email/handler/create_note_handler_spec.rb
index a2119b0dadf..4909fed6b77 100644
--- a/spec/lib/gitlab/email/handler/create_note_handler_spec.rb
+++ b/spec/lib/gitlab/email/handler/create_note_handler_spec.rb
@@ -60,6 +60,67 @@ describe Gitlab::Email::Handler::CreateNoteHandler, lib: true do
     it "raises an InvalidNoteError" do
       expect { receiver.execute }.to raise_error(Gitlab::Email::InvalidNoteError)
     end
+
+    context 'because the note was commands only' do
+      let!(:email_raw) { fixture_file("emails/commands_only_reply.eml") }
+
+      context 'and current user cannot update noteable' do
+        it 'raises a CommandsOnlyNoteError' do
+          expect { receiver.execute }.to raise_error(Gitlab::Email::InvalidNoteError)
+        end
+      end
+
+      context 'and current user can update noteable' do
+        before do
+          project.team << [user, :developer]
+        end
+
+        it 'does not raise an error' do
+          expect(TodoService.new.todo_exist?(noteable, user)).to be_falsy
+
+          # One system note is created for the 'close' event
+          expect { receiver.execute }.to change { noteable.notes.count }.by(1)
+
+          expect(noteable.reload).to be_closed
+          expect(noteable.due_date).to eq(Date.tomorrow)
+          expect(TodoService.new.todo_exist?(noteable, user)).to be_truthy
+        end
+      end
+    end
+  end
+
+  context 'when the note contains slash commands' do
+    let!(:email_raw) { fixture_file("emails/commands_in_reply.eml") }
+
+    context 'and current user cannot update noteable' do
+      it 'post a note and does not update the noteable' do
+        expect(TodoService.new.todo_exist?(noteable, user)).to be_falsy
+
+        # One system note is created for the new note
+        expect { receiver.execute }.to change { noteable.notes.count }.by(1)
+
+        expect(noteable.reload).to be_open
+        expect(noteable.due_date).to be_nil
+        expect(TodoService.new.todo_exist?(noteable, user)).to be_falsy
+      end
+    end
+
+    context 'and current user can update noteable' do
+      before do
+        project.team << [user, :developer]
+      end
+
+      it 'post a note and updates the noteable' do
+        expect(TodoService.new.todo_exist?(noteable, user)).to be_falsy
+
+        # One system note is created for the new note, one for the 'close' event
+        expect { receiver.execute }.to change { noteable.notes.count }.by(2)
+
+        expect(noteable.reload).to be_closed
+        expect(noteable.due_date).to eq(Date.tomorrow)
+        expect(TodoService.new.todo_exist?(noteable, user)).to be_truthy
+      end
+    end
   end
 
   context "when the reply is blank" do
diff --git a/spec/lib/gitlab/slash_commands/command_definition_spec.rb b/spec/lib/gitlab/slash_commands/command_definition_spec.rb
new file mode 100644
index 00000000000..c9c2f314e57
--- /dev/null
+++ b/spec/lib/gitlab/slash_commands/command_definition_spec.rb
@@ -0,0 +1,173 @@
+require 'spec_helper'
+
+describe Gitlab::SlashCommands::CommandDefinition do
+  subject { described_class.new(:command) }
+
+  describe "#all_names" do
+    context "when the command has aliases" do
+      before do
+        subject.aliases = [:alias1, :alias2]
+      end
+
+      it "returns an array with the name and aliases" do
+        expect(subject.all_names).to eq([:command, :alias1, :alias2])
+      end
+    end
+
+    context "when the command doesn't have aliases" do
+      it "returns an array with the name" do
+        expect(subject.all_names).to eq([:command])
+      end
+    end
+  end
+
+  describe "#noop?" do
+    context "when the command has an action block" do
+      before do
+        subject.action_block = proc { }
+      end
+
+      it "returns false" do
+        expect(subject.noop?).to be false
+      end
+    end
+
+    context "when the command doesn't have an action block" do
+      it "returns true" do
+        expect(subject.noop?).to be true
+      end
+    end
+  end
+
+  describe "#available?" do
+    let(:opts) { { go: false } }
+
+    context "when the command has a condition block" do
+      before do
+        subject.condition_block = proc { go }
+      end
+
+      context "when the condition block returns true" do
+        before do
+          opts[:go] = true
+        end
+
+        it "returns true" do
+          expect(subject.available?(opts)).to be true
+        end
+      end
+
+      context "when the condition block returns false" do
+        it "returns false" do
+          expect(subject.available?(opts)).to be false
+        end
+      end
+    end
+
+    context "when the command doesn't have a condition block" do
+      it "returns true" do
+        expect(subject.available?(opts)).to be true
+      end
+    end
+  end
+
+  describe "#execute" do
+    let(:context) { OpenStruct.new(run: false) }
+
+    context "when the command is a noop" do
+      it "doesn't execute the command" do
+        expect(context).not_to receive(:instance_exec)
+
+        subject.execute(context, {}, nil)
+
+        expect(context.run).to be false
+      end
+    end
+
+    context "when the command is not a noop" do
+      before do
+        subject.action_block = proc { self.run = true }
+      end
+
+      context "when the command is not available" do
+        before do
+          subject.condition_block = proc { false }
+        end
+
+        it "doesn't execute the command" do
+          subject.execute(context, {}, nil)
+
+          expect(context.run).to be false
+        end
+      end
+
+      context "when the command is available" do
+        context "when the commnd has no arguments" do
+          before do
+            subject.action_block = proc { self.run = true }
+          end
+
+          context "when the command is provided an argument" do
+            it "executes the command" do
+              subject.execute(context, {}, true)
+
+              expect(context.run).to be true
+            end
+          end
+
+          context "when the command is not provided an argument" do
+            it "executes the command" do
+              subject.execute(context, {}, nil)
+
+              expect(context.run).to be true
+            end
+          end
+        end
+
+        context "when the command has 1 required argument" do
+          before do
+            subject.action_block = ->(arg) { self.run = arg }
+          end
+
+          context "when the command is provided an argument" do
+            it "executes the command" do
+              subject.execute(context, {}, true)
+
+              expect(context.run).to be true
+            end
+          end
+
+          context "when the command is not provided an argument" do
+            it "doesn't execute the command" do
+              subject.execute(context, {}, nil)
+
+              expect(context.run).to be false
+            end
+          end
+        end
+
+        context "when the command has 1 optional argument" do
+          before do
+            subject.action_block = proc { |arg = nil| self.run = arg || true }
+          end
+
+          context "when the command is provided an argument" do
+            it "executes the command" do
+              subject.execute(context, {}, true)
+
+              expect(context.run).to be true
+            end
+          end
+
+          context "when the command is not provided an argument" do
+            it "executes the command" do
+              subject.execute(context, {}, nil)
+
+              expect(context.run).to be true
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/slash_commands/dsl_spec.rb b/spec/lib/gitlab/slash_commands/dsl_spec.rb
new file mode 100644
index 00000000000..26217a0e3b2
--- /dev/null
+++ b/spec/lib/gitlab/slash_commands/dsl_spec.rb
@@ -0,0 +1,77 @@
+require 'spec_helper'
+
+describe Gitlab::SlashCommands::Dsl do
+  before :all do
+    DummyClass = Struct.new(:project) do
+      include Gitlab::SlashCommands::Dsl
+
+      desc 'A command with no args'
+      command :no_args, :none do
+        "Hello World!"
+      end
+
+      params 'The first argument'
+      command :one_arg, :once, :first do |arg1|
+        arg1
+      end
+
+      desc do
+        "A dynamic description for #{noteable.upcase}"
+      end
+      params 'The first argument', 'The second argument'
+      command :two_args do |arg1, arg2|
+        [arg1, arg2]
+      end
+
+      command :cc
+
+      condition do
+        project == 'foo'
+      end
+      command :cond_action do |arg|
+        arg
+      end
+    end
+  end
+
+  describe '.command_definitions' do
+    it 'returns an array with commands definitions' do
+      no_args_def, one_arg_def, two_args_def, cc_def, cond_action_def = DummyClass.command_definitions
+
+      expect(no_args_def.name).to eq(:no_args)
+      expect(no_args_def.aliases).to eq([:none])
+      expect(no_args_def.description).to eq('A command with no args')
+      expect(no_args_def.params).to eq([])
+      expect(no_args_def.condition_block).to be_nil
+      expect(no_args_def.action_block).to be_a_kind_of(Proc)
+
+      expect(one_arg_def.name).to eq(:one_arg)
+      expect(one_arg_def.aliases).to eq([:once, :first])
+      expect(one_arg_def.description).to eq('')
+      expect(one_arg_def.params).to eq(['The first argument'])
+      expect(one_arg_def.condition_block).to be_nil
+      expect(one_arg_def.action_block).to be_a_kind_of(Proc)
+
+      expect(two_args_def.name).to eq(:two_args)
+      expect(two_args_def.aliases).to eq([])
+      expect(two_args_def.to_h(noteable: "issue")[:description]).to eq('A dynamic description for ISSUE')
+      expect(two_args_def.params).to eq(['The first argument', 'The second argument'])
+      expect(two_args_def.condition_block).to be_nil
+      expect(two_args_def.action_block).to be_a_kind_of(Proc)
+
+      expect(cc_def.name).to eq(:cc)
+      expect(cc_def.aliases).to eq([])
+      expect(cc_def.description).to eq('')
+      expect(cc_def.params).to eq([])
+      expect(cc_def.condition_block).to be_nil
+      expect(cc_def.action_block).to be_nil
+
+      expect(cond_action_def.name).to eq(:cond_action)
+      expect(cond_action_def.aliases).to eq([])
+      expect(cond_action_def.description).to eq('')
+      expect(cond_action_def.params).to eq([])
+      expect(cond_action_def.condition_block).to be_a_kind_of(Proc)
+      expect(cond_action_def.action_block).to be_a_kind_of(Proc)
+    end
+  end
+end
diff --git a/spec/lib/gitlab/slash_commands/extractor_spec.rb b/spec/lib/gitlab/slash_commands/extractor_spec.rb
new file mode 100644
index 00000000000..1e4954c4af8
--- /dev/null
+++ b/spec/lib/gitlab/slash_commands/extractor_spec.rb
@@ -0,0 +1,215 @@
+require 'spec_helper'
+
+describe Gitlab::SlashCommands::Extractor do
+  let(:definitions) do
+    Class.new do
+      include Gitlab::SlashCommands::Dsl
+
+      command(:reopen, :open) { }
+      command(:assign) { }
+      command(:labels) { }
+      command(:power) { }
+    end.command_definitions
+  end
+
+  let(:extractor) { described_class.new(definitions) }
+
+  shared_examples 'command with no argument' do
+    it 'extracts command' do
+      msg, commands = extractor.extract_commands(original_msg)
+
+      expect(commands).to eq [['reopen']]
+      expect(msg).to eq final_msg
+    end
+  end
+
+  shared_examples 'command with a single argument' do
+    it 'extracts command' do
+      msg, commands = extractor.extract_commands(original_msg)
+
+      expect(commands).to eq [['assign', '@joe']]
+      expect(msg).to eq final_msg
+    end
+  end
+
+  shared_examples 'command with multiple arguments' do
+    it 'extracts command' do
+      msg, commands = extractor.extract_commands(original_msg)
+
+      expect(commands).to eq [['labels', '~foo ~"bar baz" label']]
+      expect(msg).to eq final_msg
+    end
+  end
+
+  describe '#extract_commands' do
+    describe 'command with no argument' do
+      context 'at the start of content' do
+        it_behaves_like 'command with no argument' do
+          let(:original_msg) { "/reopen\nworld" }
+          let(:final_msg) { "world" }
+        end
+      end
+
+      context 'in the middle of content' do
+        it_behaves_like 'command with no argument' do
+          let(:original_msg) { "hello\n/reopen\nworld" }
+          let(:final_msg) { "hello\nworld" }
+        end
+      end
+
+      context 'in the middle of a line' do
+        it 'does not extract command' do
+          msg = "hello\nworld /reopen"
+          msg, commands = extractor.extract_commands(msg)
+
+          expect(commands).to be_empty
+          expect(msg).to eq "hello\nworld /reopen"
+        end
+      end
+
+      context 'at the end of content' do
+        it_behaves_like 'command with no argument' do
+          let(:original_msg) { "hello\n/reopen" }
+          let(:final_msg) { "hello" }
+        end
+      end
+    end
+
+    describe 'command with a single argument' do
+      context 'at the start of content' do
+        it_behaves_like 'command with a single argument' do
+          let(:original_msg) { "/assign @joe\nworld" }
+          let(:final_msg) { "world" }
+        end
+      end
+
+      context 'in the middle of content' do
+        it_behaves_like 'command with a single argument' do
+          let(:original_msg) { "hello\n/assign @joe\nworld" }
+          let(:final_msg) { "hello\nworld" }
+        end
+      end
+
+      context 'in the middle of a line' do
+        it 'does not extract command' do
+          msg = "hello\nworld /assign @joe"
+          msg, commands = extractor.extract_commands(msg)
+
+          expect(commands).to be_empty
+          expect(msg).to eq "hello\nworld /assign @joe"
+        end
+      end
+
+      context 'at the end of content' do
+        it_behaves_like 'command with a single argument' do
+          let(:original_msg) { "hello\n/assign @joe" }
+          let(:final_msg) { "hello" }
+        end
+      end
+
+      context 'when argument is not separated with a space' do
+        it 'does not extract command' do
+          msg = "hello\n/assign@joe\nworld"
+          msg, commands = extractor.extract_commands(msg)
+
+          expect(commands).to be_empty
+          expect(msg).to eq "hello\n/assign@joe\nworld"
+        end
+      end
+    end
+
+    describe 'command with multiple arguments' do
+      context 'at the start of content' do
+        it_behaves_like 'command with multiple arguments' do
+          let(:original_msg) { %(/labels ~foo ~"bar baz" label\nworld) }
+          let(:final_msg) { "world" }
+        end
+      end
+
+      context 'in the middle of content' do
+        it_behaves_like 'command with multiple arguments' do
+          let(:original_msg) { %(hello\n/labels ~foo ~"bar baz" label\nworld) }
+          let(:final_msg) { "hello\nworld" }
+        end
+      end
+
+      context 'in the middle of a line' do
+        it 'does not extract command' do
+          msg = %(hello\nworld /labels ~foo ~"bar baz" label)
+          msg, commands = extractor.extract_commands(msg)
+
+          expect(commands).to be_empty
+          expect(msg).to eq %(hello\nworld /labels ~foo ~"bar baz" label)
+        end
+      end
+
+      context 'at the end of content' do
+        it_behaves_like 'command with multiple arguments' do
+          let(:original_msg) { %(hello\n/labels ~foo ~"bar baz" label) }
+          let(:final_msg) { "hello" }
+        end
+      end
+
+      context 'when argument is not separated with a space' do
+        it 'does not extract command' do
+          msg = %(hello\n/labels~foo ~"bar baz" label\nworld)
+          msg, commands = extractor.extract_commands(msg)
+
+          expect(commands).to be_empty
+          expect(msg).to eq %(hello\n/labels~foo ~"bar baz" label\nworld)
+        end
+      end
+    end
+
+    it 'extracts command with multiple arguments and various prefixes' do
+      msg = %(hello\n/power @user.name %9.10 ~"bar baz.2"\nworld)
+      msg, commands = extractor.extract_commands(msg)
+
+      expect(commands).to eq [['power', '@user.name %9.10 ~"bar baz.2"']]
+      expect(msg).to eq "hello\nworld"
+    end
+
+    it 'extracts multiple commands' do
+      msg = %(hello\n/power @user.name %9.10 ~"bar baz.2" label\nworld\n/reopen)
+      msg, commands = extractor.extract_commands(msg)
+
+      expect(commands).to eq [['power', '@user.name %9.10 ~"bar baz.2" label'], ['reopen']]
+      expect(msg).to eq "hello\nworld"
+    end
+
+    it 'does not alter original content if no command is found' do
+      msg = 'Fixes #123'
+      msg, commands = extractor.extract_commands(msg)
+
+      expect(commands).to be_empty
+      expect(msg).to eq 'Fixes #123'
+    end
+
+    it 'does not extract commands inside a blockcode' do
+      msg = "Hello\r\n```\r\nThis is some text\r\n/close\r\n/assign @user\r\n```\r\n\r\nWorld"
+      expected = msg.delete("\r")
+      msg, commands = extractor.extract_commands(msg)
+
+      expect(commands).to be_empty
+      expect(msg).to eq expected
+    end
+
+    it 'does not extract commands inside a blockquote' do
+      msg = "Hello\r\n>>>\r\nThis is some text\r\n/close\r\n/assign @user\r\n>>>\r\n\r\nWorld"
+      expected = msg.delete("\r")
+      msg, commands = extractor.extract_commands(msg)
+
+      expect(commands).to be_empty
+      expect(msg).to eq expected
+    end
+
+    it 'does not extract commands inside a HTML tag' do
+      msg = "Hello\r\n<div>\r\nThis is some text\r\n/close\r\n/assign @user\r\n</div>\r\n\r\nWorld"
+      expected = msg.delete("\r")
+      msg, commands = extractor.extract_commands(msg)
+
+      expect(commands).to be_empty
+      expect(msg).to eq expected
+    end
+  end
+end
diff --git a/spec/services/issues/close_service_spec.rb b/spec/services/issues/close_service_spec.rb
index 1318607a388..aff022a573e 100644
--- a/spec/services/issues/close_service_spec.rb
+++ b/spec/services/issues/close_service_spec.rb
@@ -3,6 +3,7 @@ require 'spec_helper'
 describe Issues::CloseService, services: true do
   let(:user) { create(:user) }
   let(:user2) { create(:user) }
+  let(:guest) { create(:user) }
   let(:issue) { create(:issue, assignee: user2) }
   let(:project) { issue.project }
   let!(:todo) { create(:todo, :assigned, user: user, project: project, target: issue, author: user2) }
@@ -10,13 +11,14 @@ describe Issues::CloseService, services: true do
   before do
     project.team << [user, :master]
     project.team << [user2, :developer]
+    project.team << [guest, :guest]
   end
 
   describe '#execute' do
     context "valid params" do
       before do
         perform_enqueued_jobs do
-          @issue = Issues::CloseService.new(project, user, {}).execute(issue)
+          @issue = described_class.new(project, user, {}).execute(issue)
         end
       end
 
@@ -39,10 +41,22 @@ describe Issues::CloseService, services: true do
       end
     end
 
+    context 'current user is not authorized to close issue' do
+      before do
+        perform_enqueued_jobs do
+          @issue = described_class.new(project, guest).execute(issue)
+        end
+      end
+
+      it 'does not close the issue' do
+        expect(@issue).to be_open
+      end
+    end
+
     context "external issue tracker" do
       before do
         allow(project).to receive(:default_issues_tracker?).and_return(false)
-        @issue = Issues::CloseService.new(project, user, {}).execute(issue)
+        @issue = described_class.new(project, user, {}).execute(issue)
       end
 
       it { expect(@issue).to be_valid }
diff --git a/spec/services/issues/create_service_spec.rb b/spec/services/issues/create_service_spec.rb
index 1ee9f3aae4d..fcc3c0a00bd 100644
--- a/spec/services/issues/create_service_spec.rb
+++ b/spec/services/issues/create_service_spec.rb
@@ -73,5 +73,7 @@ describe Issues::CreateService, services: true do
         end
       end
     end
+
+    it_behaves_like 'new issuable record that supports slash commands'
   end
 end
diff --git a/spec/services/issues/reopen_service_spec.rb b/spec/services/issues/reopen_service_spec.rb
new file mode 100644
index 00000000000..34a89fcd4e1
--- /dev/null
+++ b/spec/services/issues/reopen_service_spec.rb
@@ -0,0 +1,25 @@
+require 'spec_helper'
+
+describe Issues::ReopenService, services: true do
+  let(:guest) { create(:user) }
+  let(:issue) { create(:issue, :closed) }
+  let(:project) { issue.project }
+
+  before do
+    project.team << [guest, :guest]
+  end
+
+  describe '#execute' do
+    context 'current user is not authorized to reopen issue' do
+      before do
+        perform_enqueued_jobs do
+          @issue = described_class.new(project, guest).execute(issue)
+        end
+      end
+
+      it 'does not reopen the issue' do
+        expect(@issue).to be_closed
+      end
+    end
+  end
+end
diff --git a/spec/services/merge_requests/close_service_spec.rb b/spec/services/merge_requests/close_service_spec.rb
index 403533be5d9..24c25e4350f 100644
--- a/spec/services/merge_requests/close_service_spec.rb
+++ b/spec/services/merge_requests/close_service_spec.rb
@@ -3,6 +3,7 @@ require 'spec_helper'
 describe MergeRequests::CloseService, services: true do
   let(:user) { create(:user) }
   let(:user2) { create(:user) }
+  let(:guest) { create(:user) }
   let(:merge_request) { create(:merge_request, assignee: user2) }
   let(:project) { merge_request.project }
   let!(:todo) { create(:todo, :assigned, user: user, project: project, target: merge_request, author: user2) }
@@ -10,11 +11,12 @@ describe MergeRequests::CloseService, services: true do
   before do
     project.team << [user, :master]
     project.team << [user2, :developer]
+    project.team << [guest, :guest]
   end
 
   describe '#execute' do
     context 'valid params' do
-      let(:service) { MergeRequests::CloseService.new(project, user, {}) }
+      let(:service) { described_class.new(project, user, {}) }
 
       before do
         allow(service).to receive(:execute_hooks)
@@ -47,5 +49,17 @@ describe MergeRequests::CloseService, services: true do
         expect(todo.reload).to be_done
       end
     end
+
+    context 'current user is not authorized to close merge request' do
+      before do
+        perform_enqueued_jobs do
+          @merge_request = described_class.new(project, guest).execute(merge_request)
+        end
+      end
+
+      it 'does not close the merge request' do
+        expect(@merge_request).to be_open
+      end
+    end
   end
 end
diff --git a/spec/services/merge_requests/create_service_spec.rb b/spec/services/merge_requests/create_service_spec.rb
index b84a580967a..c1e4f8bd96b 100644
--- a/spec/services/merge_requests/create_service_spec.rb
+++ b/spec/services/merge_requests/create_service_spec.rb
@@ -17,7 +17,7 @@ describe MergeRequests::CreateService, services: true do
         }
       end
 
-      let(:service) { MergeRequests::CreateService.new(project, user, opts) }
+      let(:service) { described_class.new(project, user, opts) }
 
       before do
         project.team << [user, :master]
@@ -74,5 +74,14 @@ describe MergeRequests::CreateService, services: true do
         end
       end
     end
+
+    it_behaves_like 'new issuable record that supports slash commands' do
+      let(:default_params) do
+        {
+          source_branch: 'feature',
+          target_branch: 'master'
+        }
+      end
+    end
   end
 end
diff --git a/spec/services/merge_requests/reopen_service_spec.rb b/spec/services/merge_requests/reopen_service_spec.rb
index 3419b8bf5e6..af7424a76a9 100644
--- a/spec/services/merge_requests/reopen_service_spec.rb
+++ b/spec/services/merge_requests/reopen_service_spec.rb
@@ -3,22 +3,23 @@ require 'spec_helper'
 describe MergeRequests::ReopenService, services: true do
   let(:user) { create(:user) }
   let(:user2) { create(:user) }
-  let(:merge_request) { create(:merge_request, assignee: user2) }
+  let(:guest) { create(:user) }
+  let(:merge_request) { create(:merge_request, :closed, assignee: user2) }
   let(:project) { merge_request.project }
 
   before do
     project.team << [user, :master]
     project.team << [user2, :developer]
+    project.team << [guest, :guest]
   end
 
   describe '#execute' do
     context 'valid params' do
-      let(:service) { MergeRequests::ReopenService.new(project, user, {}) }
+      let(:service) { described_class.new(project, user, {}) }
 
       before do
         allow(service).to receive(:execute_hooks)
 
-        merge_request.state = :closed
         perform_enqueued_jobs do
           service.execute(merge_request)
         end
@@ -43,5 +44,17 @@ describe MergeRequests::ReopenService, services: true do
         expect(note.note).to include 'Status changed to reopened'
       end
     end
+
+    context 'current user is not authorized to reopen merge request' do
+      before do
+        perform_enqueued_jobs do
+          @merge_request = described_class.new(project, guest).execute(merge_request)
+        end
+      end
+
+      it 'does not reopen the merge request' do
+        expect(@merge_request).to be_closed
+      end
+    end
   end
 end
diff --git a/spec/services/notes/create_service_spec.rb b/spec/services/notes/create_service_spec.rb
index 32753e84b31..93885c84dc3 100644
--- a/spec/services/notes/create_service_spec.rb
+++ b/spec/services/notes/create_service_spec.rb
@@ -4,22 +4,36 @@ describe Notes::CreateService, services: true do
   let(:project) { create(:empty_project) }
   let(:issue) { create(:issue, project: project) }
   let(:user) { create(:user) }
+  let(:opts) do
+    { note: 'Awesome comment', noteable_type: 'Issue', noteable_id: issue.id }
+  end
 
   describe '#execute' do
+    before do
+      project.team << [user, :master]
+    end
+
     context "valid params" do
       before do
-        project.team << [user, :master]
-        opts = {
-          note: 'Awesome comment',
-          noteable_type: 'Issue',
-          noteable_id: issue.id
-        }
-
         @note = Notes::CreateService.new(project, user, opts).execute
       end
 
       it { expect(@note).to be_valid }
-      it { expect(@note.note).to eq('Awesome comment') }
+      it { expect(@note.note).to eq(opts[:note]) }
+    end
+
+    describe 'note with commands' do
+      describe '/close, /label, /assign & /milestone' do
+        let(:note_text) { %(HELLO\n/close\n/assign @#{user.username}\nWORLD) }
+
+        it 'saves the note and does not alter the note text' do
+          expect_any_instance_of(Issues::UpdateService).to receive(:execute).and_call_original
+
+          note = described_class.new(project, user, opts.merge(note: note_text)).execute
+
+          expect(note.note).to eq "HELLO\nWORLD"
+        end
+      end
     end
   end
 
@@ -42,7 +56,7 @@ describe Notes::CreateService, services: true do
 
     it "creates regular note if emoji name is invalid" do
       opts = {
-        note: ':smile: moretext: ',
+        note: ':smile: moretext:',
         noteable_type: 'Issue',
         noteable_id: issue.id
       }
diff --git a/spec/services/notes/slash_commands_service_spec.rb b/spec/services/notes/slash_commands_service_spec.rb
new file mode 100644
index 00000000000..4f231aab161
--- /dev/null
+++ b/spec/services/notes/slash_commands_service_spec.rb
@@ -0,0 +1,140 @@
+require 'spec_helper'
+
+describe Notes::SlashCommandsService, services: true do
+  shared_context 'note on noteable' do
+    let(:project) { create(:empty_project) }
+    let(:master) { create(:user).tap { |u| project.team << [u, :master] } }
+    let(:assignee) { create(:user) }
+  end
+
+  shared_examples 'note on noteable that does not support slash commands' do
+    include_context 'note on noteable'
+
+    before do
+      note.note = note_text
+    end
+
+    describe 'note with only command' do
+      describe '/close, /label, /assign & /milestone' do
+        let(:note_text) { %(/close\n/assign @#{assignee.username}") }
+
+        it 'saves the note and does not alter the note text' do
+          content, command_params = service.extract_commands(note)
+
+          expect(content).to eq note_text
+          expect(command_params).to be_empty
+        end
+      end
+    end
+
+    describe 'note with command & text' do
+      describe '/close, /label, /assign & /milestone' do
+        let(:note_text) { %(HELLO\n/close\n/assign @#{assignee.username}\nWORLD) }
+
+        it 'saves the note and does not alter the note text' do
+          content, command_params = service.extract_commands(note)
+
+          expect(content).to eq note_text
+          expect(command_params).to be_empty
+        end
+      end
+    end
+  end
+
+  shared_examples 'note on noteable that supports slash commands' do
+    include_context 'note on noteable'
+
+    before do
+      note.note = note_text
+    end
+
+    let!(:milestone) { create(:milestone, project: project) }
+    let!(:labels) { create_pair(:label, project: project) }
+
+    describe 'note with only command' do
+      describe '/close, /label, /assign & /milestone' do
+        let(:note_text) do
+          %(/close\n/label ~#{labels.first.name} ~#{labels.last.name}\n/assign @#{assignee.username}\n/milestone %"#{milestone.name}")
+        end
+
+        it 'closes noteable, sets labels, assigns, and sets milestone to noteable, and leave no note' do
+          content, command_params = service.extract_commands(note)
+          service.execute(command_params, note)
+
+          expect(content).to eq ''
+          expect(note.noteable).to be_closed
+          expect(note.noteable.labels).to match_array(labels)
+          expect(note.noteable.assignee).to eq(assignee)
+          expect(note.noteable.milestone).to eq(milestone)
+        end
+      end
+
+      describe '/reopen' do
+        before do
+          note.noteable.close!
+          expect(note.noteable).to be_closed
+        end
+        let(:note_text) { '/reopen' }
+
+        it 'opens the noteable, and leave no note' do
+          content, command_params = service.extract_commands(note)
+          service.execute(command_params, note)
+
+          expect(content).to eq ''
+          expect(note.noteable).to be_open
+        end
+      end
+    end
+
+    describe 'note with command & text' do
+      describe '/close, /label, /assign & /milestone' do
+        let(:note_text) do
+          %(HELLO\n/close\n/label ~#{labels.first.name} ~#{labels.last.name}\n/assign @#{assignee.username}\n/milestone %"#{milestone.name}"\nWORLD)
+        end
+
+        it 'closes noteable, sets labels, assigns, and sets milestone to noteable' do
+          content, command_params = service.extract_commands(note)
+          service.execute(command_params, note)
+
+          expect(content).to eq "HELLO\nWORLD"
+          expect(note.noteable).to be_closed
+          expect(note.noteable.labels).to match_array(labels)
+          expect(note.noteable.assignee).to eq(assignee)
+          expect(note.noteable.milestone).to eq(milestone)
+        end
+      end
+
+      describe '/reopen' do
+        before do
+          note.noteable.close
+          expect(note.noteable).to be_closed
+        end
+        let(:note_text) { "HELLO\n/reopen\nWORLD" }
+
+        it 'opens the noteable' do
+          content, command_params = service.extract_commands(note)
+          service.execute(command_params, note)
+
+          expect(content).to eq "HELLO\nWORLD"
+          expect(note.noteable).to be_open
+        end
+      end
+    end
+  end
+
+  describe '#execute' do
+    let(:service) { described_class.new(project, master) }
+
+    it_behaves_like 'note on noteable that supports slash commands' do
+      let(:note) { build(:note_on_issue, project: project) }
+    end
+
+    it_behaves_like 'note on noteable that supports slash commands' do
+      let(:note) { build(:note_on_merge_request, project: project) }
+    end
+
+    it_behaves_like 'note on noteable that does not support slash commands' do
+      let(:note) { build(:note_on_commit, project: project) }
+    end
+  end
+end
diff --git a/spec/services/slash_commands/interpret_service_spec.rb b/spec/services/slash_commands/interpret_service_spec.rb
new file mode 100644
index 00000000000..a616275e883
--- /dev/null
+++ b/spec/services/slash_commands/interpret_service_spec.rb
@@ -0,0 +1,384 @@
+require 'spec_helper'
+
+describe SlashCommands::InterpretService, services: true do
+  let(:project) { create(:project) }
+  let(:user) { create(:user) }
+  let(:issue) { create(:issue, project: project) }
+  let(:milestone) { create(:milestone, project: project, title: '9.10') }
+  let(:inprogress) { create(:label, project: project, title: 'In Progress') }
+  let(:bug) { create(:label, project: project, title: 'Bug') }
+
+  before do
+    project.team << [user, :developer]
+  end
+
+  describe '#execute' do
+    let(:service) { described_class.new(project, user) }
+    let(:merge_request) { create(:merge_request, source_project: project) }
+
+    shared_examples 'reopen command' do
+      it 'returns state_event: "reopen" if content contains /reopen' do
+        issuable.close!
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(state_event: 'reopen')
+      end
+    end
+
+    shared_examples 'close command' do
+      it 'returns state_event: "close" if content contains /close' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(state_event: 'close')
+      end
+    end
+
+    shared_examples 'title command' do
+      it 'populates title: "A brand new title" if content contains /title A brand new title' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(title: 'A brand new title')
+      end
+    end
+
+    shared_examples 'assign command' do
+      it 'fetches assignee and populates assignee_id if content contains /assign' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(assignee_id: user.id)
+      end
+    end
+
+    shared_examples 'unassign command' do
+      it 'populates assignee_id: nil if content contains /unassign' do
+        issuable.update(assignee_id: user.id)
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(assignee_id: nil)
+      end
+    end
+
+    shared_examples 'milestone command' do
+      it 'fetches milestone and populates milestone_id if content contains /milestone' do
+        milestone # populate the milestone
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(milestone_id: milestone.id)
+      end
+    end
+
+    shared_examples 'remove_milestone command' do
+      it 'populates milestone_id: nil if content contains /remove_milestone' do
+        issuable.update(milestone_id: milestone.id)
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(milestone_id: nil)
+      end
+    end
+
+    shared_examples 'label command' do
+      it 'fetches label ids and populates add_label_ids if content contains /label' do
+        bug # populate the label
+        inprogress # populate the label
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(add_label_ids: [bug.id, inprogress.id])
+      end
+    end
+
+    shared_examples 'unlabel command' do
+      it 'fetches label ids and populates remove_label_ids if content contains /unlabel' do
+        issuable.update(label_ids: [inprogress.id]) # populate the label
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(remove_label_ids: [inprogress.id])
+      end
+    end
+
+    shared_examples 'unlabel command with no argument' do
+      it 'populates label_ids: [] if content contains /unlabel with no arguments' do
+        issuable.update(label_ids: [inprogress.id]) # populate the label
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(label_ids: [])
+      end
+    end
+
+    shared_examples 'relabel command' do
+      it 'populates label_ids: [] if content contains /relabel' do
+        issuable.update(label_ids: [bug.id]) # populate the label
+        inprogress # populate the label
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(label_ids: [inprogress.id])
+      end
+    end
+
+    shared_examples 'todo command' do
+      it 'populates todo_event: "add" if content contains /todo' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(todo_event: 'add')
+      end
+    end
+
+    shared_examples 'done command' do
+      it 'populates todo_event: "done" if content contains /done' do
+        TodoService.new.mark_todo(issuable, user)
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(todo_event: 'done')
+      end
+    end
+
+    shared_examples 'subscribe command' do
+      it 'populates subscription_event: "subscribe" if content contains /subscribe' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(subscription_event: 'subscribe')
+      end
+    end
+
+    shared_examples 'unsubscribe command' do
+      it 'populates subscription_event: "unsubscribe" if content contains /unsubscribe' do
+        issuable.subscribe(user)
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(subscription_event: 'unsubscribe')
+      end
+    end
+
+    shared_examples 'due command' do
+      it 'populates due_date: Date.new(2016, 8, 28) if content contains /due 2016-08-28' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(due_date: defined?(expected_date) ? expected_date : Date.new(2016, 8, 28))
+      end
+    end
+
+    shared_examples 'remove_due_date command' do
+      it 'populates due_date: nil if content contains /remove_due_date' do
+        issuable.update(due_date: Date.today)
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(due_date: nil)
+      end
+    end
+
+    shared_examples 'empty command' do
+      it 'populates {} if content contains an unsupported command' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to be_empty
+      end
+    end
+
+    it_behaves_like 'reopen command' do
+      let(:content) { '/reopen' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'reopen command' do
+      let(:content) { '/reopen' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'close command' do
+      let(:content) { '/close' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'close command' do
+      let(:content) { '/close' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'title command' do
+      let(:content) { '/title A brand new title' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'title command' do
+      let(:content) { '/title A brand new title' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/title' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'assign command' do
+      let(:content) { "/assign @#{user.username}" }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'assign command' do
+      let(:content) { "/assign @#{user.username}" }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/assign @abcd1234' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/assign' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'unassign command' do
+      let(:content) { '/unassign' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'unassign command' do
+      let(:content) { '/unassign' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'milestone command' do
+      let(:content) { "/milestone %#{milestone.title}" }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'milestone command' do
+      let(:content) { "/milestone %#{milestone.title}" }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'remove_milestone command' do
+      let(:content) { '/remove_milestone' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'remove_milestone command' do
+      let(:content) { '/remove_milestone' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'label command' do
+      let(:content) { %(/label ~"#{inprogress.title}" ~#{bug.title} ~unknown) }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'label command' do
+      let(:content) { %(/label ~"#{inprogress.title}" ~#{bug.title} ~unknown) }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'unlabel command' do
+      let(:content) { %(/unlabel ~"#{inprogress.title}") }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'unlabel command' do
+      let(:content) { %(/unlabel ~"#{inprogress.title}") }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'unlabel command with no argument' do
+      let(:content) { %(/unlabel) }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'unlabel command with no argument' do
+      let(:content) { %(/unlabel) }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'relabel command' do
+      let(:content) { %(/relabel ~"#{inprogress.title}") }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'relabel command' do
+      let(:content) { %(/relabel ~"#{inprogress.title}") }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'todo command' do
+      let(:content) { '/todo' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'todo command' do
+      let(:content) { '/todo' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'done command' do
+      let(:content) { '/done' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'done command' do
+      let(:content) { '/done' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'subscribe command' do
+      let(:content) { '/subscribe' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'subscribe command' do
+      let(:content) { '/subscribe' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'unsubscribe command' do
+      let(:content) { '/unsubscribe' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'unsubscribe command' do
+      let(:content) { '/unsubscribe' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'due command' do
+      let(:content) { '/due 2016-08-28' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'due command' do
+      let(:content) { '/due tomorrow' }
+      let(:issuable) { issue }
+      let(:expected_date) { Date.tomorrow }
+    end
+
+    it_behaves_like 'due command' do
+      let(:content) { '/due 5 days from now' }
+      let(:issuable) { issue }
+      let(:expected_date) { 5.days.from_now.to_date }
+    end
+
+    it_behaves_like 'due command' do
+      let(:content) { '/due in 2 days' }
+      let(:issuable) { issue }
+      let(:expected_date) { 2.days.from_now.to_date }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/due foo bar' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/due 2016-08-28' }
+      let(:issuable) { merge_request }
+    end
+
+    it_behaves_like 'remove_due_date command' do
+      let(:content) { '/remove_due_date' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/remove_due_date' }
+      let(:issuable) { merge_request }
+    end
+  end
+end
diff --git a/spec/services/todo_service_spec.rb b/spec/services/todo_service_spec.rb
index a2a1d5e6d30..296fd1bd5a4 100644
--- a/spec/services/todo_service_spec.rb
+++ b/spec/services/todo_service_spec.rb
@@ -300,6 +300,18 @@ describe TodoService, services: true do
         should_create_todo(user: author, target: unassigned_issue, action: Todo::MARKED)
       end
     end
+
+    describe '#todo_exists?' do
+      it 'returns false when no todo exist for the given issuable' do
+        expect(service.todo_exist?(unassigned_issue, author)).to be_falsy
+      end
+
+      it 'returns true when a todo exist for the given issuable' do
+        service.mark_todo(unassigned_issue, author)
+
+        expect(service.todo_exist?(unassigned_issue, author)).to be_truthy
+      end
+    end
   end
 
   describe 'Merge Requests' do
diff --git a/spec/support/issuable_create_service_slash_commands_shared_examples.rb b/spec/support/issuable_create_service_slash_commands_shared_examples.rb
new file mode 100644
index 00000000000..5f9645ed44f
--- /dev/null
+++ b/spec/support/issuable_create_service_slash_commands_shared_examples.rb
@@ -0,0 +1,83 @@
+# Specifications for behavior common to all objects with executable attributes.
+# It can take a `default_params`.
+
+shared_examples 'new issuable record that supports slash commands' do
+  let!(:project) { create(:project) }
+  let(:user) { create(:user).tap { |u| project.team << [u, :master] } }
+  let(:assignee) { create(:user) }
+  let!(:milestone) { create(:milestone, project: project) }
+  let!(:labels) { create_list(:label, 3, project: project) }
+  let(:base_params) { { title: FFaker::Lorem.sentence(3) } }
+  let(:params) { base_params.merge(defined?(default_params) ? default_params : {}).merge(example_params) }
+  let(:issuable) { described_class.new(project, user, params).execute }
+
+  context 'with labels in command only' do
+    let(:example_params) do
+      {
+        description: "/label ~#{labels.first.name} ~#{labels.second.name}\n/unlabel ~#{labels.third.name}"
+      }
+    end
+
+    it 'attaches labels to issuable' do
+      expect(issuable).to be_persisted
+      expect(issuable.label_ids).to match_array([labels.first.id, labels.second.id])
+    end
+  end
+
+  context 'with labels in params and command' do
+    let(:example_params) do
+      {
+        label_ids: [labels.second.id],
+        description: "/label ~#{labels.first.name}\n/unlabel ~#{labels.third.name}"
+      }
+    end
+
+    it 'attaches all labels to issuable' do
+      expect(issuable).to be_persisted
+      expect(issuable.label_ids).to match_array([labels.first.id, labels.second.id])
+    end
+  end
+
+  context 'with assignee and milestone in command only' do
+    let(:example_params) do
+      {
+        description: %(/assign @#{assignee.username}\n/milestone %"#{milestone.name}")
+      }
+    end
+
+    it 'assigns and sets milestone to issuable' do
+      expect(issuable).to be_persisted
+      expect(issuable.assignee).to eq(assignee)
+      expect(issuable.milestone).to eq(milestone)
+    end
+  end
+
+  context 'with assignee and milestone in params and command' do
+    let(:example_params) do
+      {
+        assignee: build_stubbed(:user),
+        milestone_id: double(:milestone),
+        description: %(/assign @#{assignee.username}\n/milestone %"#{milestone.name}")
+      }
+    end
+
+    it 'assigns and sets milestone to issuable from command' do
+      expect(issuable).to be_persisted
+      expect(issuable.assignee).to eq(assignee)
+      expect(issuable.milestone).to eq(milestone)
+    end
+  end
+
+  describe '/close' do
+    let(:example_params) do
+      {
+        description: '/close'
+      }
+    end
+
+    it 'returns an open issue' do
+      expect(issuable).to be_persisted
+      expect(issuable).to be_open
+    end
+  end
+end
diff --git a/spec/support/issuable_slash_commands_shared_examples.rb b/spec/support/issuable_slash_commands_shared_examples.rb
new file mode 100644
index 00000000000..d2a49ea5c5e
--- /dev/null
+++ b/spec/support/issuable_slash_commands_shared_examples.rb
@@ -0,0 +1,289 @@
+# Specifications for behavior common to all objects with executable attributes.
+# It takes a `issuable_type`, and expect an `issuable`.
+
+shared_examples 'issuable record that supports slash commands in its description and notes' do |issuable_type|
+  let(:master) { create(:user) }
+  let(:assignee) { create(:user, username: 'bob') }
+  let(:guest) { create(:user) }
+  let(:project) { create(:project, :public) }
+  let!(:milestone) { create(:milestone, project: project, title: 'ASAP') }
+  let!(:label_bug) { create(:label, project: project, title: 'bug') }
+  let!(:label_feature) { create(:label, project: project, title: 'feature') }
+  let(:new_url_opts) { {} }
+
+  before do
+    project.team << [master, :master]
+    project.team << [assignee, :developer]
+    project.team << [guest, :guest]
+    login_with(master)
+  end
+
+  describe "new #{issuable_type}" do
+    context 'with commands in the description' do
+      it "creates the #{issuable_type} and interpret commands accordingly" do
+        visit public_send("new_namespace_project_#{issuable_type}_path", project.namespace, project, new_url_opts)
+        fill_in "#{issuable_type}_title", with: 'bug 345'
+        fill_in "#{issuable_type}_description", with: "bug description\n/label ~bug\n/milestone %\"ASAP\""
+        click_button "Submit #{issuable_type}".humanize
+
+        issuable = project.public_send(issuable_type.to_s.pluralize).first
+
+        expect(issuable.description).to eq "bug description"
+        expect(issuable.labels).to eq [label_bug]
+        expect(issuable.milestone).to eq milestone
+        expect(page).to have_content 'bug 345'
+        expect(page).to have_content 'bug description'
+      end
+    end
+  end
+
+  describe "note on #{issuable_type}" do
+    before do
+      visit public_send("namespace_project_#{issuable_type}_path", project.namespace, project, issuable)
+    end
+
+    context 'with a note containing commands' do
+      it 'creates a note without the commands and interpret the commands accordingly' do
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "Awesome!\n/assign @bob\n/label ~bug\n/milestone %\"ASAP\""
+          click_button 'Comment'
+        end
+
+        expect(page).to have_content 'Awesome!'
+        expect(page).not_to have_content '/assign @bob'
+        expect(page).not_to have_content '/label ~bug'
+        expect(page).not_to have_content '/milestone %"ASAP"'
+
+        issuable.reload
+        note = issuable.notes.user.first
+
+        expect(note.note).to eq "Awesome!"
+        expect(issuable.assignee).to eq assignee
+        expect(issuable.labels).to eq [label_bug]
+        expect(issuable.milestone).to eq milestone
+      end
+    end
+
+    context 'with a note containing only commands' do
+      it 'does not create a note but interpret the commands accordingly' do
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/assign @bob\n/label ~bug\n/milestone %\"ASAP\""
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/assign @bob'
+        expect(page).not_to have_content '/label ~bug'
+        expect(page).not_to have_content '/milestone %"ASAP"'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        issuable.reload
+
+        expect(issuable.notes.user).to be_empty
+        expect(issuable.assignee).to eq assignee
+        expect(issuable.labels).to eq [label_bug]
+        expect(issuable.milestone).to eq milestone
+      end
+    end
+
+    context "with a note closing the #{issuable_type}" do
+      before do
+        expect(issuable).to be_open
+      end
+
+      context "when current user can close #{issuable_type}" do
+        it "closes the #{issuable_type}" do
+          page.within('.js-main-target-form') do
+            fill_in 'note[note]', with: "/close"
+            click_button 'Comment'
+          end
+
+          expect(page).not_to have_content '/close'
+          expect(page).to have_content 'Your commands have been executed!'
+
+          expect(issuable.reload).to be_closed
+        end
+      end
+
+      context "when current user cannot close #{issuable_type}" do
+        before do
+          logout
+          login_with(guest)
+          visit public_send("namespace_project_#{issuable_type}_path", project.namespace, project, issuable)
+        end
+
+        it "does not close the #{issuable_type}" do
+          page.within('.js-main-target-form') do
+            fill_in 'note[note]', with: "/close"
+            click_button 'Comment'
+          end
+
+          expect(page).not_to have_content '/close'
+          expect(page).not_to have_content 'Your commands have been executed!'
+
+          expect(issuable).to be_open
+        end
+      end
+    end
+
+    context "with a note reopening the #{issuable_type}" do
+      before do
+        issuable.close
+        expect(issuable).to be_closed
+      end
+
+      context "when current user can reopen #{issuable_type}" do
+        it "reopens the #{issuable_type}" do
+          page.within('.js-main-target-form') do
+            fill_in 'note[note]', with: "/reopen"
+            click_button 'Comment'
+          end
+
+          expect(page).not_to have_content '/reopen'
+          expect(page).to have_content 'Your commands have been executed!'
+
+          expect(issuable.reload).to be_open
+        end
+      end
+
+      context "when current user cannot reopen #{issuable_type}" do
+        before do
+          logout
+          login_with(guest)
+          visit public_send("namespace_project_#{issuable_type}_path", project.namespace, project, issuable)
+        end
+
+        it "does not reopen the #{issuable_type}" do
+          page.within('.js-main-target-form') do
+            fill_in 'note[note]', with: "/reopen"
+            click_button 'Comment'
+          end
+
+          expect(page).not_to have_content '/reopen'
+          expect(page).not_to have_content 'Your commands have been executed!'
+
+          expect(issuable).to be_closed
+        end
+      end
+    end
+
+    context "with a note changing the #{issuable_type}'s title" do
+      context "when current user can change title of #{issuable_type}" do
+        it "reopens the #{issuable_type}" do
+          page.within('.js-main-target-form') do
+            fill_in 'note[note]', with: "/title Awesome new title"
+            click_button 'Comment'
+          end
+
+          expect(page).not_to have_content '/title'
+          expect(page).to have_content 'Your commands have been executed!'
+
+          expect(issuable.reload.title).to eq 'Awesome new title'
+        end
+      end
+
+      context "when current user cannot change title of #{issuable_type}" do
+        before do
+          logout
+          login_with(guest)
+          visit public_send("namespace_project_#{issuable_type}_path", project.namespace, project, issuable)
+        end
+
+        it "does not reopen the #{issuable_type}" do
+          page.within('.js-main-target-form') do
+            fill_in 'note[note]', with: "/title Awesome new title"
+            click_button 'Comment'
+          end
+
+          expect(page).not_to have_content '/title'
+          expect(page).not_to have_content 'Your commands have been executed!'
+
+          expect(issuable.reload.title).not_to eq 'Awesome new title'
+        end
+      end
+    end
+
+    context "with a note marking the #{issuable_type} as todo" do
+      it "creates a new todo for the #{issuable_type}" do
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/todo"
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/todo'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        todos = TodosFinder.new(master).execute
+        todo = todos.first
+
+        expect(todos.size).to eq 1
+        expect(todo).to be_pending
+        expect(todo.target).to eq issuable
+        expect(todo.author).to eq master
+        expect(todo.user).to eq master
+      end
+    end
+
+    context "with a note marking the #{issuable_type} as done" do
+      before do
+        TodoService.new.mark_todo(issuable, master)
+      end
+
+      it "creates a new todo for the #{issuable_type}" do
+        todos = TodosFinder.new(master).execute
+        todo = todos.first
+
+        expect(todos.size).to eq 1
+        expect(todos.first).to be_pending
+        expect(todo.target).to eq issuable
+        expect(todo.author).to eq master
+        expect(todo.user).to eq master
+
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/done"
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/done'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        expect(todo.reload).to be_done
+      end
+    end
+
+    context "with a note subscribing to the #{issuable_type}" do
+      it "creates a new todo for the #{issuable_type}" do
+        expect(issuable.subscribed?(master)).to be_falsy
+
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/subscribe"
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/subscribe'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        expect(issuable.subscribed?(master)).to be_truthy
+      end
+    end
+
+    context "with a note unsubscribing to the #{issuable_type} as done" do
+      before do
+        issuable.subscribe(master)
+      end
+
+      it "creates a new todo for the #{issuable_type}" do
+        expect(issuable.subscribed?(master)).to be_truthy
+
+        page.within('.js-main-target-form') do
+          fill_in 'note[note]', with: "/unsubscribe"
+          click_button 'Comment'
+        end
+
+        expect(page).not_to have_content '/unsubscribe'
+        expect(page).to have_content 'Your commands have been executed!'
+
+        expect(issuable.subscribed?(master)).to be_falsy
+      end
+    end
+  end
+end