Port changes for CODEOWNERS to CE

This ports the changes for the CODEOWNERS feature to CE:
- It adds the CODEOWNERS file.
- It adds the mention of the `with-codeowners` branch in TestEnv

.gitlab/CODEOWNERS

+# Backend Maintainers are the default for all ruby files
+*.rb @ayufan @DouweM @dzaporozhets @grzesiek @nick.thomas @rspeicher @rymai @smcgivern
+*.rake @ayufan @DouweM @dzaporozhets @grzesiek @nick.thomas @rspeicher @rymai @smcgivern
+
+# Technical writing team are the default reviewers for everything in `doc/`
+/doc/ @axil @marcia
+
+# Frontend maintainers should see everything in `app/assets/`
+app/assets/ @annabeldunstone @ClemMakesApps @fatihacet @filipa @iamphill @mikegreiling @timzallmann
+
+# Someone from the database team should review changes in `db/`
+db/ @abrandl @NikolayS
+
+# Feature specific owners
+/ee/lib/gitlab/code_owners/ @reprazent

app/models/concerns/case_sensitivity.rb

@@ -9,23 +9,46 @@ module CaseSensitivity
     #
     # Unlike other ActiveRecord methods this method only operates on a Hash.
     def iwhere(params)
-      criteria   = self
-      cast_lower = Gitlab::Database.postgresql?
+      criteria = self
 
       params.each do |key, value|
-        column = ActiveRecord::Base.connection.quote_table_name(key)
+        criteria = case value
+                   when Array
+                     criteria.where(value_in(key, value))
+                   else
+                     criteria.where(value_equal(key, value))
+                   end
+      end
+
+      criteria
+    end
 
-        condition =
-          if cast_lower
-            "LOWER(#{column}) = LOWER(:value)"
-          else
-            "#{column} = :value"
-          end
+    private
+
+    def value_equal(column, value)
+      lower_value = lower_value(value)
+
+      lower_column(arel_table[column]).eq(lower_value).to_sql
+    end
 
-        criteria = criteria.where(condition, value: value)
+    def value_in(column, values)
+      lower_values = values.map do |value|
+        lower_value(value)
       end
 
-      criteria
+      lower_column(arel_table[column]).in(lower_values).to_sql
+    end
+
+    def lower_value(value)
+      return value if Gitlab::Database.mysql?
+
+      Arel::Nodes::NamedFunction.new('LOWER', [Arel::Nodes.build_quoted(value)])
+    end
+
+    def lower_column(column)
+      return column if Gitlab::Database.mysql?
+
+      column.lower
     end
   end
 end

app/models/user.rb

@@ -257,6 +257,7 @@ class User < ActiveRecord::Base
   scope :order_recent_sign_in, -> { reorder(Gitlab::Database.nulls_last_order('current_sign_in_at', 'DESC')) }
   scope :order_oldest_sign_in, -> { reorder(Gitlab::Database.nulls_last_order('current_sign_in_at', 'ASC')) }
   scope :confirmed, -> { where.not(confirmed_at: nil) }
+  scope :by_username, -> (usernames) { iwhere(username: usernames) }
 
   # Limits the users to those that have TODOs, optionally in the given state.
   #
@@ -444,11 +445,11 @@ class User < ActiveRecord::Base
     end
 
     def find_by_username(username)
-      iwhere(username: username).take
+      by_username(username).take
     end
 
     def find_by_username!(username)
-      iwhere(username: username).take!
+      by_username(username).take!
     end
 
     def find_by_personal_access_token(token_string)

app/views/projects/blob/_blob.html.haml

@@ -5,6 +5,7 @@
     %ul.blob-commit-info
       = render 'projects/commits/commit', commit: @last_commit, project: @project, ref: @ref
 
+  = render_if_exists 'projects/blob/owners', blob: blob
   = render "projects/blob/auxiliary_viewer", blob: blob
 
 #blob-content-holder.blob-content-holder

lib/gitlab/user_extractor.rb

+# frozen_string_literal: true
+
+# This class extracts all users found in a piece of text by the username or the
+# email adress
+
+module Gitlab
+  class UserExtractor
+    # Not using `Devise.email_regexp` to filter out any chars that an email
+    # does not end with and not pinning the email to a start of end of a string.
+    EMAIL_REGEXP = /(?<email>([^@\s]+@[^@\s]+(?<!\W)))/
+    USERNAME_REGEXP = User.reference_pattern
+
+    def initialize(text)
+      @text = text
+    end
+
+    def users
+      return User.none unless @text.present?
+
+      @users ||= User.from("(#{union.to_sql}) users")
+    end
+
+    def usernames
+      matches[:usernames]
+    end
+
+    def emails
+      matches[:emails]
+    end
+
+    def references
+      @references ||= matches.values.flatten
+    end
+
+    def matches
+      @matches ||= {
+        emails: @text.scan(EMAIL_REGEXP).flatten.uniq,
+        usernames: @text.scan(USERNAME_REGEXP).flatten.uniq
+      }
+    end
+
+    private
+
+    def union
+      relations = []
+
+      relations << User.by_any_email(emails) if emails.any?
+      relations << User.by_username(usernames) if usernames.any?
+
+      Gitlab::SQL::Union.new(relations)
+    end
+  end
+end

spec/lib/gitlab/user_extractor_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::UserExtractor do
+  let(:text) do
+    <<~TXT
+    This is a long texth that mentions some users.
+    @user-1, @user-2 and user@gitlab.org take a walk in the park.
+    There they meet @user-4 that was out with other-user@gitlab.org.
+    @user-1 thought it was late, so went home straight away
+    TXT
+  end
+  subject(:extractor) { described_class.new(text) }
+
+  describe '#users' do
+    it 'returns an empty relation when nil was passed' do
+      extractor = described_class.new(nil)
+
+      expect(extractor.users).to be_empty
+      expect(extractor.users).to be_a(ActiveRecord::Relation)
+    end
+
+    it 'returns the user case insensitive for usernames' do
+      user = create(:user, username: "USER-4")
+
+      expect(extractor.users).to include(user)
+    end
+
+    it 'returns users by primary email' do
+      user = create(:user, email: 'user@gitlab.org')
+
+      expect(extractor.users).to include(user)
+    end
+
+    it 'returns users by secondary email' do
+      user = create(:email, email: 'other-user@gitlab.org').user
+
+      expect(extractor.users).to include(user)
+    end
+  end
+
+  describe '#matches' do
+    it 'includes all mentioned email adresses' do
+      expect(extractor.matches[:emails]).to contain_exactly('user@gitlab.org', 'other-user@gitlab.org')
+    end
+
+    it 'includes all mentioned usernames' do
+      expect(extractor.matches[:usernames]).to contain_exactly('user-1', 'user-2', 'user-4')
+    end
+  end
+
+  describe '#references' do
+    it 'includes all user-references once' do
+      expect(extractor.references).to contain_exactly('user-1', 'user-2', 'user@gitlab.org', 'user-4', 'other-user@gitlab.org')
+    end
+  end
+end

spec/models/concerns/case_sensitivity_spec.rb

@@ -3,186 +3,50 @@ require 'spec_helper'
 describe CaseSensitivity do
   describe '.iwhere' do
     let(:connection) { ActiveRecord::Base.connection }
-    let(:model)      { Class.new { include CaseSensitivity } }
-
-    describe 'using PostgreSQL' do
-      before do
-        allow(Gitlab::Database).to receive(:postgresql?).and_return(true)
-        allow(Gitlab::Database).to receive(:mysql?).and_return(false)
-      end
-
-      describe 'with a single column/value pair' do
-        it 'returns the criteria for a column and a value' do
-          criteria = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:foo)
-            .and_return('"foo"')
-
-          expect(model).to receive(:where)
-            .with(%q{LOWER("foo") = LOWER(:value)}, value: 'bar')
-            .and_return(criteria)
-
-          expect(model.iwhere(foo: 'bar')).to eq(criteria)
-        end
-
-        it 'returns the criteria for a column with a table, and a value' do
-          criteria = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:'foo.bar')
-            .and_return('"foo"."bar"')
-
-          expect(model).to receive(:where)
-            .with(%q{LOWER("foo"."bar") = LOWER(:value)}, value: 'bar')
-            .and_return(criteria)
-
-          expect(model.iwhere('foo.bar'.to_sym => 'bar')).to eq(criteria)
-        end
-      end
-
-      describe 'with multiple column/value pairs' do
-        it 'returns the criteria for a column and a value' do
-          initial = double(:criteria)
-          final   = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:foo)
-            .and_return('"foo"')
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:bar)
-            .and_return('"bar"')
-
-          expect(model).to receive(:where)
-            .with(%q{LOWER("foo") = LOWER(:value)}, value: 'bar')
-            .and_return(initial)
-
-          expect(initial).to receive(:where)
-            .with(%q{LOWER("bar") = LOWER(:value)}, value: 'baz')
-            .and_return(final)
-
-          got = model.iwhere(foo: 'bar', bar: 'baz')
-
-          expect(got).to eq(final)
-        end
-
-        it 'returns the criteria for a column with a table, and a value' do
-          initial = double(:criteria)
-          final   = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:'foo.bar')
-            .and_return('"foo"."bar"')
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:'foo.baz')
-            .and_return('"foo"."baz"')
-
-          expect(model).to receive(:where)
-            .with(%q{LOWER("foo"."bar") = LOWER(:value)}, value: 'bar')
-            .and_return(initial)
-
-          expect(initial).to receive(:where)
-            .with(%q{LOWER("foo"."baz") = LOWER(:value)}, value: 'baz')
-            .and_return(final)
-
-          got = model.iwhere('foo.bar'.to_sym => 'bar',
-                             'foo.baz'.to_sym => 'baz')
-
-          expect(got).to eq(final)
-        end
+    let(:model) do
+      Class.new(ActiveRecord::Base) do
+        include CaseSensitivity
+        self.table_name = 'namespaces'
       end
     end
 
-    describe 'using MySQL' do
-      before do
-        allow(Gitlab::Database).to receive(:postgresql?).and_return(false)
-        allow(Gitlab::Database).to receive(:mysql?).and_return(true)
-      end
-
-      describe 'with a single column/value pair' do
-        it 'returns the criteria for a column and a value' do
-          criteria = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:foo)
-            .and_return('`foo`')
-
-          expect(model).to receive(:where)
-            .with(%q{`foo` = :value}, value: 'bar')
-            .and_return(criteria)
+    let!(:model_1) { model.create(path: 'mOdEl-1', name: 'mOdEl 1') }
+    let!(:model_2) { model.create(path: 'mOdEl-2', name: 'mOdEl 2') }
 
-          expect(model.iwhere(foo: 'bar')).to eq(criteria)
-        end
+    it 'finds a single instance by a single attribute regardless of case' do
+      expect(model.iwhere(path: 'MODEL-1')).to contain_exactly(model_1)
+    end
 
-        it 'returns the criteria for a column with a table, and a value' do
-          criteria = double(:criteria)
+    it 'finds multiple instances by a single attribute regardless of case' do
+      expect(model.iwhere(path: %w(MODEL-1 model-2))).to contain_exactly(model_1, model_2)
+    end
 
-          expect(connection).to receive(:quote_table_name)
-            .with(:'foo.bar')
-            .and_return('`foo`.`bar`')
+    it 'finds instances by multiple attributes' do
+      expect(model.iwhere(path: %w(MODEL-1 model-2), name: 'model 1'))
+        .to contain_exactly(model_1)
+    end
 
-          expect(model).to receive(:where)
-            .with(%q{`foo`.`bar` = :value}, value: 'bar')
-            .and_return(criteria)
+    # Using `mysql` & `postgresql` metadata-tags here because both adapters build
+    # the query slightly differently
+    context 'for MySQL', :mysql do
+      it 'builds a simple query' do
+        query = model.iwhere(path: %w(MODEL-1 model-2), name: 'model 1').to_sql
+        expected_query = <<~QRY.strip
+        SELECT `namespaces`.* FROM `namespaces` WHERE (`namespaces`.`path` IN ('MODEL-1', 'model-2')) AND (`namespaces`.`name` = 'model 1')
+        QRY
 
-          expect(model.iwhere('foo.bar'.to_sym => 'bar'))
-            .to eq(criteria)
-        end
+        expect(query).to eq(expected_query)
       end
+    end
 
-      describe 'with multiple column/value pairs' do
-        it 'returns the criteria for a column and a value' do
-          initial = double(:criteria)
-          final   = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:foo)
-            .and_return('`foo`')
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:bar)
-            .and_return('`bar`')
-
-          expect(model).to receive(:where)
-            .with(%q{`foo` = :value}, value: 'bar')
-            .and_return(initial)
-
-          expect(initial).to receive(:where)
-            .with(%q{`bar` = :value}, value: 'baz')
-            .and_return(final)
-
-          got = model.iwhere(foo: 'bar', bar: 'baz')
-
-          expect(got).to eq(final)
-        end
-
-        it 'returns the criteria for a column with a table, and a value' do
-          initial = double(:criteria)
-          final   = double(:criteria)
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:'foo.bar')
-            .and_return('`foo`.`bar`')
-
-          expect(connection).to receive(:quote_table_name)
-            .with(:'foo.baz')
-            .and_return('`foo`.`baz`')
-
-          expect(model).to receive(:where)
-            .with(%q{`foo`.`bar` = :value}, value: 'bar')
-            .and_return(initial)
-
-          expect(initial).to receive(:where)
-            .with(%q{`foo`.`baz` = :value}, value: 'baz')
-            .and_return(final)
-
-          got = model.iwhere('foo.bar'.to_sym => 'bar',
-                             'foo.baz'.to_sym => 'baz')
+    context 'for PostgreSQL', :postgresql do
+      it 'builds a query using LOWER' do
+        query = model.iwhere(path: %w(MODEL-1 model-2), name: 'model 1').to_sql
+        expected_query = <<~QRY.strip
+        SELECT \"namespaces\".* FROM \"namespaces\" WHERE (LOWER(\"namespaces\".\"path\") IN (LOWER('MODEL-1'), LOWER('model-2'))) AND (LOWER(\"namespaces\".\"name\") = LOWER('model 1'))
+        QRY
 
-          expect(got).to eq(final)
-        end
+        expect(query).to eq(expected_query)
       end
     end
   end

spec/models/user_spec.rb

@@ -405,6 +405,23 @@ describe User do
         end
       end
     end
+
+    describe '.by_username' do
+      it 'finds users regardless of the case passed' do
+        user = create(:user, username: 'CaMeLcAsEd')
+        user2 = create(:user, username: 'UPPERCASE')
+
+        expect(described_class.by_username(%w(CAMELCASED uppercase)))
+          .to contain_exactly(user, user2)
+      end
+
+      it 'finds a single user regardless of the case passed' do
+        user = create(:user, username: 'CaMeLcAsEd')
+
+        expect(described_class.by_username('CAMELCASED'))
+          .to contain_exactly(user)
+      end
+    end
   end
 
   describe "Respond to" do

spec/support/helpers/test_env.rb

@@ -52,7 +52,8 @@ module TestEnv
     'add_images_and_changes'             => '010d106',
     'update-gitlab-shell-v-6-0-1'        => '2f61d70',
     'update-gitlab-shell-v-6-0-3'        => 'de78448',
-    '2-mb-file'                          => 'bf12d25'
+    '2-mb-file'                          => 'bf12d25',
+    'with-codeowners'                    => '219560e'
   }.freeze
 
   # gitlab-test-fork is a fork of gitlab-fork, but we don't necessarily