Merge branch 'master' into ide-workbench-bar

41 files changed, 610 insertions, 227 deletions

diff --git a/app/assets/javascripts/boards/models/list.js b/app/assets/javascripts/boards/models/list.js
index e210d69895e..7144f4190e7 100644
--- a/app/assets/javascripts/boards/models/list.js
+++ b/app/assets/javascripts/boards/models/list.js
@@ -113,6 +113,8 @@ class List {
         issue.id = data.id;
         issue.iid = data.iid;
         issue.project = data.project;
+        issue.path = data.real_path;
+        issue.referencePath = data.reference_path;
 
         if (this.issuesSize > 1) {
           const moveBeforeId = this.issues[1].id;
diff --git a/app/assets/javascripts/create_merge_request_dropdown.js b/app/assets/javascripts/create_merge_request_dropdown.js
index fb1fc9cd32e..a88b6971f90 100644
--- a/app/assets/javascripts/create_merge_request_dropdown.js
+++ b/app/assets/javascripts/create_merge_request_dropdown.js
@@ -84,20 +84,21 @@ export default class CreateMergeRequestDropdown {
         if (data.can_create_branch) {
           this.available();
           this.enable();
+          this.updateBranchName(data.suggested_branch_name);
 
           if (!this.droplabInitialized) {
             this.droplabInitialized = true;
             this.initDroplab();
             this.bindEvents();
           }
-        } else if (data.has_related_branch) {
+        } else {
           this.hide();
         }
       })
       .catch(() => {
         this.unavailable();
         this.disable();
-        Flash('Failed to check if a new branch can be created.');
+        Flash(__('Failed to check related branches.'));
       });
   }
 
@@ -409,13 +410,16 @@ export default class CreateMergeRequestDropdown {
     this.unavailableButton.classList.remove('hide');
   }
 
+  updateBranchName(suggestedBranchName) {
+    this.branchInput.value = suggestedBranchName;
+    this.updateCreatePaths('branch', suggestedBranchName);
+  }
+
   updateInputState(target, ref, result) {
     // target - 'branch' or 'ref' - which the input field we are searching a ref for.
     // ref - string - what a user typed.
     // result - string - what has been found on backend.
 
-    const pathReplacement = `$1${ref}`;
-
     // If a found branch equals exact the same text a user typed,
     // that means a new branch cannot be created as it already exists.
     if (ref === result) {
@@ -426,18 +430,12 @@ export default class CreateMergeRequestDropdown {
         this.refIsValid = true;
         this.refInput.dataset.value = ref;
         this.showAvailableMessage('ref');
-        this.createBranchPath = this.createBranchPath.replace(this.regexps.ref.createBranchPath,
-          pathReplacement);
-        this.createMrPath = this.createMrPath.replace(this.regexps.ref.createMrPath,
-          pathReplacement);
+        this.updateCreatePaths(target, ref);
       }
     } else if (target === 'branch') {
       this.branchIsValid = true;
       this.showAvailableMessage('branch');
-      this.createBranchPath = this.createBranchPath.replace(this.regexps.branch.createBranchPath,
-        pathReplacement);
-      this.createMrPath = this.createMrPath.replace(this.regexps.branch.createMrPath,
-        pathReplacement);
+      this.updateCreatePaths(target, ref);
     } else {
       this.refIsValid = false;
       this.refInput.dataset.value = ref;
@@ -457,4 +455,15 @@ export default class CreateMergeRequestDropdown {
       this.disableCreateAction();
     }
   }
+
+  // target - 'branch' or 'ref'
+  // ref - string - the new value to use as branch or ref
+  updateCreatePaths(target, ref) {
+    const pathReplacement = `$1${ref}`;
+
+    this.createBranchPath = this.createBranchPath.replace(this.regexps[target].createBranchPath,
+      pathReplacement);
+    this.createMrPath = this.createMrPath.replace(this.regexps[target].createMrPath,
+      pathReplacement);
+  }
 }
diff --git a/app/assets/javascripts/due_date_select.js b/app/assets/javascripts/due_date_select.js
index 842a4255f08..4164149dd06 100644
--- a/app/assets/javascripts/due_date_select.js
+++ b/app/assets/javascripts/due_date_select.js
@@ -2,7 +2,9 @@
 
 import $ from 'jquery';
 import Pikaday from 'pikaday';
+import { __ } from '~/locale';
 import axios from './lib/utils/axios_utils';
+import { timeFor } from './lib/utils/datetime_utility';
 import { parsePikadayDate, pikadayToString } from './lib/utils/datefix';
 
 class DueDateSelect {
@@ -14,6 +16,7 @@ class DueDateSelect {
     this.$dropdownParent = $dropdownParent;
     this.$datePicker = $dropdownParent.find('.js-due-date-calendar');
     this.$block = $block;
+    this.$sidebarCollapsedValue = $block.find('.sidebar-collapsed-icon');
     this.$selectbox = $dropdown.closest('.selectbox');
     this.$value = $block.find('.value');
     this.$valueContent = $block.find('.value-content');
@@ -128,7 +131,8 @@ class DueDateSelect {
 
   submitSelectedDate(isDropdown) {
     const selectedDateValue = this.datePayload[this.abilityName].due_date;
-    const displayedDateStyle = this.displayedDate !== 'No due date' ? 'bold' : 'no-value';
+    const hasDueDate = this.displayedDate !== 'No due date';
+    const displayedDateStyle = hasDueDate ? 'bold' : 'no-value';
 
     this.$loading.removeClass('hidden').fadeIn();
 
@@ -145,10 +149,13 @@ class DueDateSelect {
 
     return axios.put(this.issueUpdateURL, this.datePayload)
       .then(() => {
+        const tooltipText = hasDueDate ? `${__('Due date')}<br />${selectedDateValue} (${timeFor(selectedDateValue)})` : __('Due date');
         if (isDropdown) {
           this.$dropdown.trigger('loaded.gl.dropdown');
           this.$dropdown.dropdown('toggle');
         }
+        this.$sidebarCollapsedValue.attr('data-original-title', tooltipText);
+
         return this.$loading.fadeOut();
       });
   }
diff --git a/app/assets/javascripts/ide/lib/common/model.js b/app/assets/javascripts/ide/lib/common/model.js
index d47b6704176..016dcda1fa1 100644
--- a/app/assets/javascripts/ide/lib/common/model.js
+++ b/app/assets/javascripts/ide/lib/common/model.js
@@ -32,7 +32,7 @@ export default class Model {
       );
     }
 
-    this.events = new Map();
+    this.events = new Set();
 
     this.updateContent = this.updateContent.bind(this);
     this.updateNewContent = this.updateNewContent.bind(this);
@@ -76,10 +76,11 @@ export default class Model {
   }
 
   onChange(cb) {
-    this.events.set(
-      this.path,
-      this.disposable.add(this.model.onDidChangeContent(e => cb(this, e))),
-    );
+    this.events.add(this.disposable.add(this.model.onDidChangeContent(e => cb(this, e))));
+  }
+
+  onDispose(cb) {
+    this.events.add(cb);
   }
 
   updateContent({ content, changed }) {
@@ -96,6 +97,11 @@ export default class Model {
 
   dispose() {
     this.disposable.dispose();
+
+    this.events.forEach(cb => {
+      if (typeof cb === 'function') cb();
+    });
+
     this.events.clear();
 
     eventHub.$off(`editor.update.model.dispose.${this.file.key}`, this.dispose);
diff --git a/app/assets/javascripts/ide/lib/decorations/controller.js b/app/assets/javascripts/ide/lib/decorations/controller.js
index 42904774747..13d477bb2cf 100644
--- a/app/assets/javascripts/ide/lib/decorations/controller.js
+++ b/app/assets/javascripts/ide/lib/decorations/controller.js
@@ -38,6 +38,15 @@ export default class DecorationsController {
     );
   }
 
+  hasDecorations(model) {
+    return this.decorations.has(model.url);
+  }
+
+  removeDecorations(model) {
+    this.decorations.delete(model.url);
+    this.editorDecorations.delete(model.url);
+  }
+
   dispose() {
     this.decorations.clear();
     this.editorDecorations.clear();
diff --git a/app/assets/javascripts/ide/lib/diff/controller.js b/app/assets/javascripts/ide/lib/diff/controller.js
index b136545ad11..f579424cf33 100644
--- a/app/assets/javascripts/ide/lib/diff/controller.js
+++ b/app/assets/javascripts/ide/lib/diff/controller.js
@@ -3,7 +3,7 @@ import { throttle } from 'underscore';
 import DirtyDiffWorker from './diff_worker';
 import Disposable from '../common/disposable';
 
-export const getDiffChangeType = (change) => {
+export const getDiffChangeType = change => {
   if (change.modified) {
     return 'modified';
   } else if (change.added) {
@@ -16,12 +16,7 @@ export const getDiffChangeType = (change) => {
 };
 
 export const getDecorator = change => ({
-  range: new monaco.Range(
-    change.lineNumber,
-    1,
-    change.endLineNumber,
-    1,
-  ),
+  range: new monaco.Range(change.lineNumber, 1, change.endLineNumber, 1),
   options: {
     isWholeLine: true,
     linesDecorationsClassName: `dirty-diff dirty-diff-${getDiffChangeType(change)}`,
@@ -31,6 +26,7 @@ export const getDecorator = change => ({
 export default class DirtyDiffController {
   constructor(modelManager, decorationsController) {
     this.disposable = new Disposable();
+    this.models = new Map();
     this.editorSimpleWorker = null;
     this.modelManager = modelManager;
     this.decorationsController = decorationsController;
@@ -42,7 +38,15 @@ export default class DirtyDiffController {
   }
 
   attachModel(model) {
+    if (this.models.has(model.url)) return;
+
     model.onChange(() => this.throttledComputeDiff(model));
+    model.onDispose(() => {
+      this.decorationsController.removeDecorations(model);
+      this.models.delete(model.url);
+    });
+
+    this.models.set(model.url, model);
   }
 
   computeDiff(model) {
@@ -54,7 +58,11 @@ export default class DirtyDiffController {
   }
 
   reDecorate(model) {
-    this.decorationsController.decorate(model);
+    if (this.decorationsController.hasDecorations(model)) {
+      this.decorationsController.decorate(model);
+    } else {
+      this.computeDiff(model);
+    }
   }
 
   decorate({ data }) {
@@ -65,6 +73,7 @@ export default class DirtyDiffController {
 
   dispose() {
     this.disposable.dispose();
+    this.models.clear();
 
     this.dirtyDiffWorker.removeEventListener('message', this.decorate);
     this.dirtyDiffWorker.terminate();
diff --git a/app/assets/javascripts/labels_select.js b/app/assets/javascripts/labels_select.js
index d0050abb8e9..9b62cfb8206 100644
--- a/app/assets/javascripts/labels_select.js
+++ b/app/assets/javascripts/labels_select.js
@@ -83,7 +83,7 @@ export default class LabelsSelect {
         $dropdown.trigger('loading.gl.dropdown');
         axios.put(issueUpdateURL, data)
           .then(({ data }) => {
-            var labelCount, template, labelTooltipTitle, labelTitles;
+            var labelCount, template, labelTooltipTitle, labelTitles, formattedLabels;
             $loading.fadeOut();
             $dropdown.trigger('loaded.gl.dropdown');
             $selectbox.hide();
@@ -115,8 +115,7 @@ export default class LabelsSelect {
               labelTooltipTitle = labelTitles.join(', ');
             }
             else {
-              labelTooltipTitle = '';
-              $sidebarLabelTooltip.tooltip('destroy');
+              labelTooltipTitle = __('Labels');
             }
 
             $sidebarLabelTooltip
diff --git a/app/assets/javascripts/milestone_select.js b/app/assets/javascripts/milestone_select.js
index d0a2b27b0e6..7e9a50a885d 100644
--- a/app/assets/javascripts/milestone_select.js
+++ b/app/assets/javascripts/milestone_select.js
@@ -4,6 +4,7 @@
 
 import $ from 'jquery';
 import _ from 'underscore';
+import { __ } from '~/locale';
 import axios from './lib/utils/axios_utils';
 import { timeFor } from './lib/utils/datetime_utility';
 import ModalStore from './boards/stores/modal_store';
@@ -25,7 +26,7 @@ export default class MilestoneSelect {
     }
 
     $els.each((i, dropdown) => {
-      let collapsedSidebarLabelTemplate, milestoneLinkNoneTemplate, milestoneLinkTemplate, selectedMilestone, selectedMilestoneDefault;
+      let milestoneLinkNoneTemplate, milestoneLinkTemplate, selectedMilestone, selectedMilestoneDefault;
       const $dropdown = $(dropdown);
       const projectId = $dropdown.data('projectId');
       const milestonesUrl = $dropdown.data('milestones');
@@ -52,7 +53,6 @@ export default class MilestoneSelect {
       if (issueUpdateURL) {
         milestoneLinkTemplate = _.template('<a href="/<%- full_path %>/milestones/<%- iid %>" class="bold has-tooltip" data-container="body" title="<%- remaining %>"><%- title %></a>');
         milestoneLinkNoneTemplate = '<span class="no-value">None</span>';
-        collapsedSidebarLabelTemplate = _.template('<span class="has-tooltip" data-container="body" title="<%- name %><br /><%- remaining %>" data-placement="left" data-html="true"> <%- title %> </span>');
       }
       return $dropdown.glDropdown({
         showMenuAbove: showMenuAbove,
@@ -214,10 +214,16 @@ export default class MilestoneSelect {
                   data.milestone.remaining = timeFor(data.milestone.due_date);
                   data.milestone.name = data.milestone.title;
                   $value.html(milestoneLinkTemplate(data.milestone));
-                  return $sidebarCollapsedValue.find('span').html(collapsedSidebarLabelTemplate(data.milestone));
+                  return $sidebarCollapsedValue
+                    .attr('data-original-title', `${data.milestone.name}<br />${data.milestone.remaining}`)
+                    .find('span')
+                    .text(data.milestone.title);
                 } else {
                   $value.html(milestoneLinkNoneTemplate);
-                  return $sidebarCollapsedValue.find('span').text('No');
+                  return $sidebarCollapsedValue
+                    .attr('data-original-title', __('Milestone'))
+                    .find('span')
+                    .text(__('None'));
                 }
               })
               .catch(() => {
diff --git a/app/assets/javascripts/notes.js b/app/assets/javascripts/notes.js
index 2121907dff0..96f2b3eac98 100644
--- a/app/assets/javascripts/notes.js
+++ b/app/assets/javascripts/notes.js
@@ -1427,7 +1427,7 @@ export default class Notes {
     const { discussion_html } = data;
     const lines = $(discussion_html).find('.line_holder');
     lines.addClass('fade-in');
-    $container.find('tbody').prepend(lines);
+    $container.find('.diff-content > table > tbody').prepend(lines);
     const fileHolder = $container.find('.file-holder');
     $container.find('.line-holder-placeholder').remove();
     syntaxHighlight(fileHolder);
diff --git a/app/assets/javascripts/pages/users/activity_calendar.js b/app/assets/javascripts/pages/users/activity_calendar.js
index 8ce938c958b..cbc2d80ee18 100644
--- a/app/assets/javascripts/pages/users/activity_calendar.js
+++ b/app/assets/javascripts/pages/users/activity_calendar.js
@@ -19,7 +19,7 @@ function getSystemDate(systemUtcOffsetSeconds) {
   const date = new Date();
   const localUtcOffsetMinutes = 0 - date.getTimezoneOffset();
   const systemUtcOffsetMinutes = systemUtcOffsetSeconds / 60;
-  date.setMinutes((date.getMinutes() - localUtcOffsetMinutes) + systemUtcOffsetMinutes);
+  date.setMinutes(date.getMinutes() - localUtcOffsetMinutes + systemUtcOffsetMinutes);
   return date;
 }
 
@@ -35,18 +35,36 @@ function formatTooltipText({ date, count }) {
   return `${contribText}<br />${dateDayName} ${dateText}`;
 }
 
-const initColorKey = () => d3.scaleLinear().range(['#acd5f2', '#254e77']).domain([0, 3]);
+const initColorKey = () =>
+  d3
+    .scaleLinear()
+    .range(['#acd5f2', '#254e77'])
+    .domain([0, 3]);
 
 export default class ActivityCalendar {
-  constructor(container, timestamps, calendarActivitiesPath, utcOffset = 0) {
+  constructor(container, timestamps, calendarActivitiesPath, utcOffset = 0, firstDayOfWeek = 0) {
     this.calendarActivitiesPath = calendarActivitiesPath;
     this.clickDay = this.clickDay.bind(this);
     this.currentSelectedDate = '';
     this.daySpace = 1;
     this.daySize = 15;
-    this.daySizeWithSpace = this.daySize + (this.daySpace * 2);
-    this.monthNames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
+    this.daySizeWithSpace = this.daySize + this.daySpace * 2;
+    this.monthNames = [
+      'Jan',
+      'Feb',
+      'Mar',
+      'Apr',
+      'May',
+      'Jun',
+      'Jul',
+      'Aug',
+      'Sep',
+      'Oct',
+      'Nov',
+      'Dec',
+    ];
     this.months = [];
+    this.firstDayOfWeek = firstDayOfWeek;
 
     // Loop through the timestamps to create a group of objects
     // The group of objects will be grouped based on the day of the week they are
@@ -70,7 +88,7 @@ export default class ActivityCalendar {
 
       // Create a new group array if this is the first day of the week
       // or if is first object
-      if ((day === 0 && i !== 0) || i === 0) {
+      if ((day === this.firstDayOfWeek && i !== 0) || i === 0) {
         this.timestampsTmp.push([]);
         group += 1;
       }
@@ -109,21 +127,30 @@ export default class ActivityCalendar {
   }
 
   renderSvg(container, group) {
-    const width = ((group + 1) * this.daySizeWithSpace) + this.getExtraWidthPadding(group);
-    return d3.select(container)
+    const width = (group + 1) * this.daySizeWithSpace + this.getExtraWidthPadding(group);
+    return d3
+      .select(container)
       .append('svg')
-        .attr('width', width)
-        .attr('height', 167)
-        .attr('class', 'contrib-calendar');
+      .attr('width', width)
+      .attr('height', 167)
+      .attr('class', 'contrib-calendar');
+  }
+
+  dayYPos(day) {
+    return this.daySizeWithSpace * ((day + 7 - this.firstDayOfWeek) % 7);
   }
 
   renderDays() {
-    this.svg.selectAll('g').data(this.timestampsTmp).enter().append('g')
+    this.svg
+      .selectAll('g')
+      .data(this.timestampsTmp)
+      .enter()
+      .append('g')
       .attr('transform', (group, i) => {
         _.each(group, (stamp, a) => {
           if (a === 0 && stamp.day === 0) {
             const month = stamp.date.getMonth();
-            const x = (this.daySizeWithSpace * i) + 1 + this.daySizeWithSpace;
+            const x = this.daySizeWithSpace * i + 1 + this.daySizeWithSpace;
             const lastMonth = _.last(this.months);
             if (
               lastMonth == null ||
@@ -133,86 +160,113 @@ export default class ActivityCalendar {
             }
           }
         });
-        return `translate(${(this.daySizeWithSpace * i) + 1 + this.daySizeWithSpace}, 18)`;
+        return `translate(${this.daySizeWithSpace * i + 1 + this.daySizeWithSpace}, 18)`;
       })
       .selectAll('rect')
-        .data(stamp => stamp)
-        .enter()
-        .append('rect')
-          .attr('x', '0')
-          .attr('y', stamp => this.daySizeWithSpace * stamp.day)
-          .attr('width', this.daySize)
-          .attr('height', this.daySize)
-          .attr('fill', stamp => (
-            stamp.count !== 0 ? this.color(Math.min(stamp.count, 40)) : '#ededed'
-          ))
-          .attr('title', stamp => formatTooltipText(stamp))
-          .attr('class', 'user-contrib-cell js-tooltip')
-          .attr('data-container', 'body')
-          .on('click', this.clickDay);
+      .data(stamp => stamp)
+      .enter()
+      .append('rect')
+      .attr('x', '0')
+      .attr('y', stamp => this.dayYPos(stamp.day))
+      .attr('width', this.daySize)
+      .attr('height', this.daySize)
+      .attr(
+        'fill',
+        stamp => (stamp.count !== 0 ? this.color(Math.min(stamp.count, 40)) : '#ededed'),
+      )
+      .attr('title', stamp => formatTooltipText(stamp))
+      .attr('class', 'user-contrib-cell js-tooltip')
+      .attr('data-container', 'body')
+      .on('click', this.clickDay);
   }
 
   renderDayTitles() {
     const days = [
       {
         text: 'M',
-        y: 29 + (this.daySizeWithSpace * 1),
-      }, {
+        y: 29 + this.dayYPos(1),
+      },
+      {
         text: 'W',
-        y: 29 + (this.daySizeWithSpace * 3),
-      }, {
+        y: 29 + this.dayYPos(2),
+      },
+      {
         text: 'F',
-        y: 29 + (this.daySizeWithSpace * 5),
+        y: 29 + this.dayYPos(3),
       },
     ];
-    this.svg.append('g')
+    this.svg
+      .append('g')
       .selectAll('text')
-        .data(days)
-        .enter()
-        .append('text')
-          .attr('text-anchor', 'middle')
-          .attr('x', 8)
-          .attr('y', day => day.y)
-          .text(day => day.text)
-          .attr('class', 'user-contrib-text');
+      .data(days)
+      .enter()
+      .append('text')
+      .attr('text-anchor', 'middle')
+      .attr('x', 8)
+      .attr('y', day => day.y)
+      .text(day => day.text)
+      .attr('class', 'user-contrib-text');
   }
 
   renderMonths() {
-    this.svg.append('g')
+    this.svg
+      .append('g')
       .attr('direction', 'ltr')
       .selectAll('text')
-        .data(this.months)
-        .enter()
-        .append('text')
-          .attr('x', date => date.x)
-          .attr('y', 10)
-          .attr('class', 'user-contrib-text')
-          .text(date => this.monthNames[date.month]);
+      .data(this.months)
+      .enter()
+      .append('text')
+      .attr('x', date => date.x)
+      .attr('y', 10)
+      .attr('class', 'user-contrib-text')
+      .text(date => this.monthNames[date.month]);
   }
 
   renderKey() {
-    const keyValues = ['no contributions', '1-9 contributions', '10-19 contributions', '20-29 contributions', '30+ contributions'];
-    const keyColors = ['#ededed', this.colorKey(0), this.colorKey(1), this.colorKey(2), this.colorKey(3)];
+    const keyValues = [
+      'no contributions',
+      '1-9 contributions',
+      '10-19 contributions',
+      '20-29 contributions',
+      '30+ contributions',
+    ];
+    const keyColors = [
+      '#ededed',
+      this.colorKey(0),
+      this.colorKey(1),
+      this.colorKey(2),
+      this.colorKey(3),
+    ];
 
-    this.svg.append('g')
-      .attr('transform', `translate(18, ${(this.daySizeWithSpace * 8) + 16})`)
+    this.svg
+      .append('g')
+      .attr('transform', `translate(18, ${this.daySizeWithSpace * 8 + 16})`)
       .selectAll('rect')
-        .data(keyColors)
-        .enter()
-        .append('rect')
-          .attr('width', this.daySize)
-          .attr('height', this.daySize)
-          .attr('x', (color, i) => this.daySizeWithSpace * i)
-          .attr('y', 0)
-          .attr('fill', color => color)
-          .attr('class', 'js-tooltip')
-          .attr('title', (color, i) => keyValues[i])
-          .attr('data-container', 'body');
+      .data(keyColors)
+      .enter()
+      .append('rect')
+      .attr('width', this.daySize)
+      .attr('height', this.daySize)
+      .attr('x', (color, i) => this.daySizeWithSpace * i)
+      .attr('y', 0)
+      .attr('fill', color => color)
+      .attr('class', 'js-tooltip')
+      .attr('title', (color, i) => keyValues[i])
+      .attr('data-container', 'body');
   }
 
   initColor() {
-    const colorRange = ['#ededed', this.colorKey(0), this.colorKey(1), this.colorKey(2), this.colorKey(3)];
-    return d3.scaleThreshold().domain([0, 10, 20, 30]).range(colorRange);
+    const colorRange = [
+      '#ededed',
+      this.colorKey(0),
+      this.colorKey(1),
+      this.colorKey(2),
+      this.colorKey(3),
+    ];
+    return d3
+      .scaleThreshold()
+      .domain([0, 10, 20, 30])
+      .range(colorRange);
   }
 
   clickDay(stamp) {
@@ -227,14 +281,15 @@ export default class ActivityCalendar {
 
       $('.user-calendar-activities').html(LOADING_HTML);
 
-      axios.get(this.calendarActivitiesPath, {
-        params: {
-          date,
-        },
-        responseType: 'text',
-      })
-      .then(({ data }) => $('.user-calendar-activities').html(data))
-      .catch(() => flash(__('An error occurred while retrieving calendar activity')));
+      axios
+        .get(this.calendarActivitiesPath, {
+          params: {
+            date,
+          },
+          responseType: 'text',
+        })
+        .then(({ data }) => $('.user-calendar-activities').html(data))
+        .catch(() => flash(__('An error occurred while retrieving calendar activity')));
     } else {
       this.currentSelectedDate = '';
       $('.user-calendar-activities').html('');
diff --git a/app/assets/javascripts/right_sidebar.js b/app/assets/javascripts/right_sidebar.js
index 2088a49590a..6eb0b62fa1c 100644
--- a/app/assets/javascripts/right_sidebar.js
+++ b/app/assets/javascripts/right_sidebar.js
@@ -5,6 +5,7 @@ import _ from 'underscore';
 import Cookies from 'js-cookie';
 import flash from './flash';
 import axios from './lib/utils/axios_utils';
+import { __ } from './locale';
 
 function Sidebar(currentUser) {
   this.toggleTodo = this.toggleTodo.bind(this);
@@ -41,12 +42,14 @@ Sidebar.prototype.addEventListeners = function() {
 };
 
 Sidebar.prototype.sidebarToggleClicked = function (e, triggered) {
-  var $allGutterToggleIcons, $this, $thisIcon;
+  var $allGutterToggleIcons, $this, isExpanded, tooltipLabel;
   e.preventDefault();
   $this = $(this);
-  $thisIcon = $this.find('i');
+  isExpanded = $this.find('i').hasClass('fa-angle-double-right');
+  tooltipLabel = isExpanded ? __('Expand sidebar') : __('Collapse sidebar');
   $allGutterToggleIcons = $('.js-sidebar-toggle i');
-  if ($thisIcon.hasClass('fa-angle-double-right')) {
+
+  if (isExpanded) {
     $allGutterToggleIcons.removeClass('fa-angle-double-right').addClass('fa-angle-double-left');
     $('aside.right-sidebar').removeClass('right-sidebar-expanded').addClass('right-sidebar-collapsed');
     $('.layout-page').removeClass('right-sidebar-expanded').addClass('right-sidebar-collapsed');
@@ -57,6 +60,9 @@ Sidebar.prototype.sidebarToggleClicked = function (e, triggered) {
 
     if (gl.lazyLoader) gl.lazyLoader.loadCheck();
   }
+
+  $this.attr('data-original-title', tooltipLabel);
+
   if (!triggered) {
     Cookies.set("collapsed_gutter", $('.right-sidebar').hasClass('right-sidebar-collapsed'));
   }
diff --git a/app/assets/javascripts/sidebar/components/assignees/assignees.vue b/app/assets/javascripts/sidebar/components/assignees/assignees.vue
index 1e7f46454bf..2d00e8ac7e0 100644
--- a/app/assets/javascripts/sidebar/components/assignees/assignees.vue
+++ b/app/assets/javascripts/sidebar/components/assignees/assignees.vue
@@ -1,6 +1,12 @@
 <script>
+import { __ } from '~/locale';
+import tooltip from '~/vue_shared/directives/tooltip';
+
 export default {
   name: 'Assignees',
+  directives: {
+    tooltip,
+  },
   props: {
     rootPath: {
       type: String,
@@ -14,6 +20,11 @@ export default {
       type: Boolean,
       required: true,
     },
+    issuableType: {
+      type: String,
+      require: true,
+      default: 'issue',
+    },
   },
   data() {
     return {
@@ -62,6 +73,12 @@ export default {
         names.push(`+ ${this.users.length - maxRender} more`);
       }
 
+      if (!this.users.length) {
+        const emptyTooltipLabel = this.issuableType === 'issue' ?
+          __('Assignee(s)') : __('Assignee');
+        names.push(emptyTooltipLabel);
+      }
+
       return names.join(', ');
     },
     sidebarAvatarCounter() {
@@ -109,7 +126,8 @@ export default {
   <div>
     <div
       class="sidebar-collapsed-icon sidebar-collapsed-user"
-      :class="{ 'multiple-users': hasMoreThanOneAssignee, 'has-tooltip': hasAssignees }"
+      :class="{ 'multiple-users': hasMoreThanOneAssignee }"
+      v-tooltip
       data-container="body"
       data-placement="left"
       :title="collapsedTooltipTitle"
diff --git a/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.vue b/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.vue
index 3c6b9c27814..b04a2eff798 100644
--- a/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.vue
+++ b/app/assets/javascripts/sidebar/components/assignees/sidebar_assignees.vue
@@ -1,9 +1,9 @@
 <script>
-import Flash from '../../../flash';
+import Flash from '~/flash';
+import eventHub from '~/sidebar/event_hub';
+import Store from '~/sidebar/stores/sidebar_store';
 import AssigneeTitle from './assignee_title.vue';
 import Assignees from './assignees.vue';
-import Store from '../../stores/sidebar_store';
-import eventHub from '../../event_hub';
 
 export default {
   name: 'SidebarAssignees',
@@ -25,6 +25,11 @@ export default {
       required: false,
       default: false,
     },
+    issuableType: {
+      type: String,
+      require: true,
+      default: 'issue',
+    },
   },
   data() {
     return {
@@ -90,6 +95,7 @@ export default {
       :users="store.assignees"
       :editable="store.editable"
       @assign-self="assignSelf"
+      :issuable-type="issuableType"
     />
   </div>
 </template>
diff --git a/app/assets/javascripts/sidebar/components/confidential/confidential_issue_sidebar.vue b/app/assets/javascripts/sidebar/components/confidential/confidential_issue_sidebar.vue
index ceb02309959..7f0de722f61 100644
--- a/app/assets/javascripts/sidebar/components/confidential/confidential_issue_sidebar.vue
+++ b/app/assets/javascripts/sidebar/components/confidential/confidential_issue_sidebar.vue
@@ -1,15 +1,19 @@
 <script>
-import Flash from '../../../flash';
+import { __ } from '~/locale';
+import Flash from '~/flash';
+import tooltip from '~/vue_shared/directives/tooltip';
+import Icon from '~/vue_shared/components/icon.vue';
+import eventHub from '~/sidebar/event_hub';
 import editForm from './edit_form.vue';
-import Icon from '../../../vue_shared/components/icon.vue';
-import { __ } from '../../../locale';
-import eventHub from '../../event_hub';
 
 export default {
   components: {
     editForm,
     Icon,
   },
+  directives: {
+    tooltip,
+  },
   props: {
     isConfidential: {
       required: true,
@@ -33,6 +37,9 @@ export default {
     confidentialityIcon() {
       return this.isConfidential ? 'eye-slash' : 'eye';
     },
+    tooltipLabel() {
+      return this.isConfidential ? __('Confidential') : __('Not confidential');
+    },
   },
   created() {
     eventHub.$on('closeConfidentialityForm', this.toggleForm);
@@ -65,6 +72,10 @@ export default {
     <div
       class="sidebar-collapsed-icon"
       @click="toggleForm"
+      v-tooltip
+      data-container="body"
+      data-placement="left"
+      :title="tooltipLabel"
     >
       <icon
         :name="confidentialityIcon"
diff --git a/app/assets/javascripts/sidebar/components/lock/lock_issue_sidebar.vue b/app/assets/javascripts/sidebar/components/lock/lock_issue_sidebar.vue
index e4893451af3..1a5e7b67eca 100644
--- a/app/assets/javascripts/sidebar/components/lock/lock_issue_sidebar.vue
+++ b/app/assets/javascripts/sidebar/components/lock/lock_issue_sidebar.vue
@@ -1,15 +1,22 @@
 <script>
+import { __ } from '~/locale';
 import Flash from '~/flash';
+import tooltip from '~/vue_shared/directives/tooltip';
+import issuableMixin from '~/vue_shared/mixins/issuable';
+import Icon from '~/vue_shared/components/icon.vue';
+import eventHub from '~/sidebar/event_hub';
 import editForm from './edit_form.vue';
-import issuableMixin from '../../../vue_shared/mixins/issuable';
-import Icon from '../../../vue_shared/components/icon.vue';
-import eventHub from '../../event_hub';
 
 export default {
   components: {
     editForm,
     Icon,
   },
+
+  directives: {
+    tooltip,
+  },
+
   mixins: [issuableMixin],
 
   props: {
@@ -44,6 +51,10 @@ export default {
     isLockDialogOpen() {
       return this.mediator.store.isLockDialogOpen;
     },
+
+    tooltipLabel() {
+      return this.isLocked ? __('Locked') : __('Unlocked');
+    },
   },
 
   created() {
@@ -85,6 +96,10 @@ export default {
     <div
       class="sidebar-collapsed-icon"
       @click="toggleForm"
+      v-tooltip
+      data-container="body"
+      data-placement="left"
+      :title="tooltipLabel"
     >
       <icon
         :name="lockIcon"
diff --git a/app/assets/javascripts/sidebar/components/participants/participants.vue b/app/assets/javascripts/sidebar/components/participants/participants.vue
index 006a6d2905d..6d95153af28 100644
--- a/app/assets/javascripts/sidebar/components/participants/participants.vue
+++ b/app/assets/javascripts/sidebar/components/participants/participants.vue
@@ -1,9 +1,13 @@
 <script>
-  import { __, n__, sprintf } from '../../../locale';
-  import loadingIcon from '../../../vue_shared/components/loading_icon.vue';
-  import userAvatarImage from '../../../vue_shared/components/user_avatar/user_avatar_image.vue';
+  import { __, n__, sprintf } from '~/locale';
+  import tooltip from '~/vue_shared/directives/tooltip';
+  import loadingIcon from '~/vue_shared/components/loading_icon.vue';
+  import userAvatarImage from '~/vue_shared/components/user_avatar/user_avatar_image.vue';
 
   export default {
+    directives: {
+      tooltip,
+    },
     components: {
       loadingIcon,
       userAvatarImage,
@@ -72,7 +76,13 @@
 
 <template>
   <div>
-    <div class="sidebar-collapsed-icon">
+    <div
+      class="sidebar-collapsed-icon"
+      v-tooltip
+      data-container="body"
+      data-placement="left"
+      :title="participantLabel"
+    >
       <i
         class="fa fa-users"
         aria-hidden="true"
diff --git a/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.vue b/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.vue
index 3b86f1145d1..9d9ee9dea4d 100644
--- a/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.vue
+++ b/app/assets/javascripts/sidebar/components/time_tracking/collapsed_state.vue
@@ -1,12 +1,17 @@
 <script>
-  import icon from '../../../vue_shared/components/icon.vue';
-  import { abbreviateTime } from '../../../lib/utils/pretty_time';
+  import { __, sprintf } from '~/locale';
+  import { abbreviateTime } from '~/lib/utils/pretty_time';
+  import icon from '~/vue_shared/components/icon.vue';
+  import tooltip from '~/vue_shared/directives/tooltip';
 
   export default {
     name: 'TimeTrackingCollapsedState',
     components: {
       icon,
     },
+    directives: {
+      tooltip,
+    },
     props: {
       showComparisonState: {
         type: Boolean,
@@ -79,6 +84,21 @@
 
         return '';
       },
+      timeTrackedTooltipText() {
+        let title;
+        if (this.showComparisonState) {
+          title = __('Time remaining');
+        } else if (this.showEstimateOnlyState) {
+          title = __('Estimated');
+        } else if (this.showSpentOnlyState) {
+          title = __('Time spent');
+        }
+
+        return sprintf('%{title}: %{text}', ({ title, text: this.text }));
+      },
+      tooltipText() {
+        return this.showNoTimeTrackingState ? __('Time tracking') : this.timeTrackedTooltipText;
+      },
     },
     methods: {
       abbreviateTime(timeStr) {
@@ -89,7 +109,13 @@
 </script>
 
 <template>
-  <div class="sidebar-collapsed-icon">
+  <div
+    class="sidebar-collapsed-icon"
+    v-tooltip
+    data-container="body"
+    data-placement="left"
+    :title="tooltipText"
+  >
     <icon name="timer" />
     <div class="time-tracking-collapsed-summary">
       <div :class="divClass">
diff --git a/app/assets/javascripts/sidebar/mount_sidebar.js b/app/assets/javascripts/sidebar/mount_sidebar.js
index 9f5d852260e..26eb4cffba3 100644
--- a/app/assets/javascripts/sidebar/mount_sidebar.js
+++ b/app/assets/javascripts/sidebar/mount_sidebar.js
@@ -27,6 +27,7 @@ function mountAssigneesComponent(mediator) {
         mediator,
         field: el.dataset.field,
         signedIn: el.hasAttribute('data-signed-in'),
+        issuableType: gl.utils.isInIssuePage() ? 'issue' : 'merge_request',
       },
     }),
   });
diff --git a/app/assets/javascripts/users_select.js b/app/assets/javascripts/users_select.js
index 520a0b3f424..8486019897d 100644
--- a/app/assets/javascripts/users_select.js
+++ b/app/assets/javascripts/users_select.js
@@ -5,6 +5,7 @@
 import $ from 'jquery';
 import _ from 'underscore';
 import axios from './lib/utils/axios_utils';
+import { __ } from './locale';
 import ModalStore from './boards/stores/modal_store';
 
 // TODO: remove eventHub hack after code splitting refactor
@@ -182,7 +183,7 @@ function UsersSelect(currentUser, els, options = {}) {
 
         return axios.put(issueURL, data)
           .then(({ data }) => {
-            var user;
+            var user, tooltipTitle;
             $dropdown.trigger('loaded.gl.dropdown');
             $loading.fadeOut();
             if (data.assignee) {
@@ -191,15 +192,17 @@ function UsersSelect(currentUser, els, options = {}) {
                 username: data.assignee.username,
                 avatar: data.assignee.avatar_url
               };
+              tooltipTitle = _.escape(user.name);
             } else {
               user = {
                 name: 'Unassigned',
                 username: '',
                 avatar: ''
               };
+              tooltipTitle = __('Assignee');
             }
             $value.html(assigneeTemplate(user));
-            $collapsedSidebar.attr('title', _.escape(user.name)).tooltip('fixTitle');
+            $collapsedSidebar.attr('title', tooltipTitle).tooltip('fixTitle');
             return $collapsedSidebar.html(collapsedAssigneeTemplate(user));
           });
       };
diff --git a/app/assets/javascripts/vue_shared/components/sidebar/toggle_sidebar.vue b/app/assets/javascripts/vue_shared/components/sidebar/toggle_sidebar.vue
index 8211d425b1f..de6f8c32e74 100644
--- a/app/assets/javascripts/vue_shared/components/sidebar/toggle_sidebar.vue
+++ b/app/assets/javascripts/vue_shared/components/sidebar/toggle_sidebar.vue
@@ -1,18 +1,29 @@
 <script>
-  export default {
-    name: 'ToggleSidebar',
-    props: {
-      collapsed: {
-        type: Boolean,
-        required: true,
-      },
+import { __ } from '~/locale';
+import tooltip from '~/vue_shared/directives/tooltip';
+
+export default {
+  name: 'ToggleSidebar',
+  directives: {
+    tooltip,
+  },
+  props: {
+    collapsed: {
+      type: Boolean,
+      required: true,
+    },
+  },
+  computed: {
+    tooltipLabel() {
+      return this.collapsed ? __('Expand sidebar') : __('Collapse sidebar');
     },
-    methods: {
-      toggle() {
-        this.$emit('toggle');
-      },
+  },
+  methods: {
+    toggle() {
+      this.$emit('toggle');
     },
-  };
+  },
+};
 </script>
 
 <template>
@@ -20,6 +31,10 @@
     type="button"
     class="btn btn-blank gutter-toggle btn-sidebar-action"
     @click="toggle"
+    v-tooltip
+    data-container="body"
+    data-placement="left"
+    :title="tooltipLabel"
   >
     <i
       aria-label="toggle collapse"
diff --git a/app/assets/stylesheets/framework/variables.scss b/app/assets/stylesheets/framework/variables.scss
index 37223175199..8c44ebc85ef 100644
--- a/app/assets/stylesheets/framework/variables.scss
+++ b/app/assets/stylesheets/framework/variables.scss
@@ -247,6 +247,7 @@ $btn-sm-side-margin: 7px;
 $btn-xs-side-margin: 5px;
 $issue-status-expired: $orange-500;
 $issuable-sidebar-color: $gl-text-color-secondary;
+$sidebar-block-hover-color: #ebebeb;
 $group-path-color: #999;
 $namespace-kind-color: #aaa;
 $panel-heading-link-color: #777;
@@ -373,6 +374,8 @@ $dropdown-hover-color: $blue-400;
 $link-active-background: rgba(0, 0, 0, 0.04);
 $link-hover-background: rgba(0, 0, 0, 0.06);
 $inactive-badge-background: rgba(0, 0, 0, 0.08);
+$sidebar-toggle-height: 60px;
+$sidebar-milestone-toggle-bottom-margin: 10px;
 
 /*
 * Buttons
diff --git a/app/assets/stylesheets/pages/issuable.scss b/app/assets/stylesheets/pages/issuable.scss
index 2c0ed976301..b2dad4a358a 100644
--- a/app/assets/stylesheets/pages/issuable.scss
+++ b/app/assets/stylesheets/pages/issuable.scss
@@ -187,7 +187,12 @@
       padding-left: 10px;
 
       &:hover {
-        color: $gray-darkest;
+        color: $gl-text-color;
+      }
+
+      &:hover,
+      &:focus {
+        text-decoration: none;
       }
     }
 
@@ -368,6 +373,14 @@
       padding: 15px 0 0;
       border-bottom: 0;
       overflow: hidden;
+
+      &:hover {
+        background-color: $sidebar-block-hover-color;
+      }
+
+      &.issuable-sidebar-header {
+        padding-top: 0;
+      }
     }
 
     .participants {
@@ -380,8 +393,17 @@
 
     .gutter-toggle {
       width: 100%;
+      height: $sidebar-toggle-height;
       margin-left: 0;
-      padding-left: 25px;
+      padding-left: 0;
+      border-bottom: 1px solid $border-gray-dark;
+    }
+
+    a.gutter-toggle {
+      display: flex;
+      justify-content: center;
+      flex-direction: column;
+      text-align: center;
     }
 
     .sidebar-collapsed-icon {
@@ -428,10 +450,10 @@
 
       .btn-clipboard {
         border: 0;
+        background: transparent;
         color: $issuable-sidebar-color;
 
         &:hover {
-          background: transparent;
           color: $gl-text-color;
         }
       }
diff --git a/app/assets/stylesheets/pages/milestone.scss b/app/assets/stylesheets/pages/milestone.scss
index 3af8d80daab..bac3b70c734 100644
--- a/app/assets/stylesheets/pages/milestone.scss
+++ b/app/assets/stylesheets/pages/milestone.scss
@@ -53,10 +53,6 @@
 }
 
 .milestone-sidebar {
-  .gutter-toggle {
-    margin-bottom: 10px;
-  }
-
   .milestone-progress {
     .title {
       padding-top: 5px;
@@ -102,7 +98,17 @@
     margin-right: 0;
   }
 
+  .right-sidebar-expanded & {
+    .gutter-toggle {
+      margin-bottom: $sidebar-milestone-toggle-bottom-margin;
+    }
+  }
+
   .right-sidebar-collapsed & {
+    .milestone-progress {
+      padding-top: 0;
+    }
+
     .reference {
       border-top: 1px solid $border-gray-normal;
     }
diff --git a/app/controllers/projects/issues_controller.rb b/app/controllers/projects/issues_controller.rb
index 767e492f566..d69015c8665 100644
--- a/app/controllers/projects/issues_controller.rb
+++ b/app/controllers/projects/issues_controller.rb
@@ -134,11 +134,11 @@ class Projects::IssuesController < Projects::ApplicationController
   def can_create_branch
     can_create = current_user &&
       can?(current_user, :push_code, @project) &&
-      @issue.can_be_worked_on?(current_user)
+      @issue.can_be_worked_on?
 
     respond_to do |format|
       format.json do
-        render json: { can_create_branch: can_create, has_related_branch: @issue.has_related_branch? }
+        render json: { can_create_branch: can_create, suggested_branch_name: @issue.suggested_branch_name }
       end
     end
   end
@@ -177,7 +177,7 @@ class Projects::IssuesController < Projects::ApplicationController
   end
 
   def authorize_create_merge_request!
-    render_404 unless can?(current_user, :push_code, @project) && @issue.can_be_worked_on?(current_user)
+    render_404 unless can?(current_user, :push_code, @project) && @issue.can_be_worked_on?
   end
 
   def render_issue_json
diff --git a/app/controllers/projects/repositories_controller.rb b/app/controllers/projects/repositories_controller.rb
index 937b0e39cbd..d01f324e6fd 100644
--- a/app/controllers/projects/repositories_controller.rb
+++ b/app/controllers/projects/repositories_controller.rb
@@ -28,11 +28,12 @@ class Projects::RepositoriesController < Projects::ApplicationController
   end
 
   def assign_archive_vars
-    @id = params[:id]
-
-    return unless @id
-
-    @ref, @filename = extract_ref(@id)
+    if params[:id]
+      @ref, @filename = extract_ref(params[:id])
+    else
+      @ref = params[:ref]
+      @filename = nil
+    end
   rescue InvalidPathError
     render_404
   end
diff --git a/app/helpers/issuables_helper.rb b/app/helpers/issuables_helper.rb
index 06c3e569c84..f39a62bccc8 100644
--- a/app/helpers/issuables_helper.rb
+++ b/app/helpers/issuables_helper.rb
@@ -9,6 +9,32 @@ module IssuablesHelper
     "right-sidebar-#{sidebar_gutter_collapsed? ? 'collapsed' : 'expanded'}"
   end
 
+  def sidebar_gutter_tooltip_text
+    sidebar_gutter_collapsed? ? _('Expand sidebar') : _('Collapse sidebar')
+  end
+
+  def sidebar_assignee_tooltip_label(issuable)
+    if issuable.assignee
+      issuable.assignee.name
+    else
+      issuable.allows_multiple_assignees? ? _('Assignee(s)') : _('Assignee')
+    end
+  end
+
+  def sidebar_due_date_tooltip_label(issuable)
+    if issuable.due_date
+      "#{_('Due date')}<br />#{due_date_remaining_days(issuable)}"
+    else
+      _('Due date')
+    end
+  end
+
+  def due_date_remaining_days(issuable)
+    remaining_days_in_words = remaining_days_in_words(issuable)
+
+    "#{issuable.due_date.to_s(:medium)} (#{remaining_days_in_words})"
+  end
+
   def multi_label_name(current_labels, default_label)
     if current_labels && current_labels.any?
       title = current_labels.first.try(:title)
@@ -153,10 +179,14 @@ module IssuablesHelper
   def issuable_labels_tooltip(labels, limit: 5)
     first, last = labels.partition.with_index { |_, i| i < limit  }
 
-    label_names = first.collect(&:name)
-    label_names << "and #{last.size} more" unless last.empty?
+    if labels && labels.any?
+      label_names = first.collect(&:name)
+      label_names << "and #{last.size} more" unless last.empty?
 
-    label_names.join(', ')
+      label_names.join(', ')
+    else
+      _("Labels")
+    end
   end
 
   def issuables_state_counter_text(issuable_type, state, display_count)
@@ -321,7 +351,7 @@ module IssuablesHelper
   def issuable_todo_button_data(issuable, todo, is_collapsed)
     {
       todo_text: "Add todo",
-      mark_text: "Mark done",
+      mark_text: "Mark todo as done",
       todo_icon: (is_collapsed ? icon('plus-square') : nil),
       mark_icon: (is_collapsed ? icon('check-square', class: 'todo-undone') : nil),
       issuable_id: issuable.id,
diff --git a/app/helpers/milestones_helper.rb b/app/helpers/milestones_helper.rb
index be8cb358de2..e8caab3e50c 100644
--- a/app/helpers/milestones_helper.rb
+++ b/app/helpers/milestones_helper.rb
@@ -1,4 +1,6 @@
 module MilestonesHelper
+  include EntityDateHelper
+
   def milestones_filter_path(opts = {})
     if @project
       project_milestones_path(@project, opts)
@@ -72,6 +74,19 @@ module MilestonesHelper
     end
   end
 
+  def milestone_progress_tooltip_text(milestone)
+    has_issues = milestone.total_issues_count(current_user) > 0
+
+    if has_issues
+      [
+        _('Progress'),
+        _("%{percent}%% complete") % { percent: milestone.percent_complete(current_user) }
+      ].join('<br />')
+    else
+      _('Progress')
+    end
+  end
+
   def milestone_progress_bar(milestone)
     options = {
       class: 'progress-bar progress-bar-success',
@@ -95,27 +110,69 @@ module MilestonesHelper
   end
 
   def milestone_tooltip_title(milestone)
-    if milestone.due_date
-      [milestone.due_date.to_s(:medium), "(#{milestone_remaining_days(milestone)})"].join(' ')
+    if milestone
+      "#{milestone.title}<br />#{milestone_tooltip_due_date(milestone)}"
+    else
+      _('Milestone')
     end
   end
 
-  def milestone_remaining_days(milestone)
-    if milestone.expired?
-      content_tag(:strong, 'Past due')
-    elsif milestone.upcoming?
-      content_tag(:strong, 'Upcoming')
-    elsif milestone.due_date
-      time_ago = time_ago_in_words(milestone.due_date)
-      content = time_ago.gsub(/\d+/) { |match| "<strong>#{match}</strong>" }
-      content.slice!("about ")
-      content << " remaining"
-      content.html_safe
-    elsif milestone.start_date && milestone.start_date.past?
-      days    = milestone.elapsed_days
-      content = content_tag(:strong, days)
-      content << " #{'day'.pluralize(days)} elapsed"
+  def milestone_time_for(date, date_type)
+    title = date_type == :start ? "Start date" : "End date"
+
+    if date
+      time_ago = time_ago_in_words(date)
+      time_ago.slice!("about ")
+
+      time_ago << if date.past?
+                    " ago"
+                  else
+                    " remaining"
+                  end
+
+      content = [
+        title,
+        "<br />",
+        date.to_s(:medium),
+        "(#{time_ago})"
+      ].join(" ")
+
       content.html_safe
+    else
+      title
+    end
+  end
+
+  def milestone_issues_tooltip_text(milestone)
+    issues = milestone.count_issues_by_state(current_user)
+
+    return _("Issues") if issues.empty?
+
+    content = []
+
+    content << n_("1 open issue", "%d open issues", issues["opened"]) % issues["opened"] if issues["opened"]
+    content << n_("1 closed issue", "%d closed issues", issues["closed"]) % issues["closed"] if issues["closed"]
+
+    content.join('<br />').html_safe
+  end
+
+  def milestone_merge_requests_tooltip_text(milestone)
+    merge_requests = milestone.merge_requests
+
+    return _("Merge requests") if merge_requests.empty?
+
+    content = []
+
+    content << n_("1 open merge request", "%d open merge requests", merge_requests.opened.count) % merge_requests.opened.count if merge_requests.opened.any?
+    content << n_("1 closed merge request", "%d closed merge requests", merge_requests.closed.count) % merge_requests.closed.count if merge_requests.closed.any?
+    content << n_("1 merged merge request", "%d merged merge requests", merge_requests.merged.count) % merge_requests.merged.count if merge_requests.merged.any?
+
+    content.join('<br />').html_safe
+  end
+
+  def milestone_tooltip_due_date(milestone)
+    if milestone.due_date
+      "#{milestone.due_date.to_s(:medium)} (#{remaining_days_in_words(milestone)})"
     end
   end
 
diff --git a/app/models/commit.rb b/app/models/commit.rb
index de860df4b9c..9750e9298ec 100644
--- a/app/models/commit.rb
+++ b/app/models/commit.rb
@@ -248,7 +248,7 @@ class Commit
   end
 
   def notes_with_associations
-    notes.includes(:author)
+    notes.includes(:author, :award_emoji)
   end
 
   def merge_requests
diff --git a/app/models/concerns/milestoneish.rb b/app/models/concerns/milestoneish.rb
index 5130ecec472..967fd9c5eea 100644
--- a/app/models/concerns/milestoneish.rb
+++ b/app/models/concerns/milestoneish.rb
@@ -102,14 +102,14 @@ module Milestoneish
     Gitlab::TimeTrackingFormatter.output(total_issue_time_estimate)
   end
 
-  private
-
   def count_issues_by_state(user)
     memoize_per_user(user, :count_issues_by_state) do
       issues_visible_to_user(user).reorder(nil).group(:state).count
     end
   end
 
+  private
+
   def memoize_per_user(user, method_name)
     memoized_users[method_name][user&.id] ||= yield
   end
diff --git a/app/models/concerns/uniquify.rb b/app/models/concerns/uniquify.rb
index a7fe5951b6e..549a76da20e 100644
--- a/app/models/concerns/uniquify.rb
+++ b/app/models/concerns/uniquify.rb
@@ -1,13 +1,21 @@
+# Uniquify
+#
+# Return a version of the given 'base' string that is unique
+# by appending a counter to it. Uniqueness is determined by
+# repeated calls to the passed block.
+#
+# You can pass an initial value for the counter, if not given
+# counting starts from 1.
+#
+# If `base` is a function/proc, we expect that calling it with a
+# candidate counter returns a string to test/return.
 class Uniquify
-  # Return a version of the given 'base' string that is unique
-  # by appending a counter to it. Uniqueness is determined by
-  # repeated calls to the passed block.
-  #
-  # If `base` is a function/proc, we expect that calling it with a
-  # candidate counter returns a string to test/return.
+  def initialize(counter = nil)
+    @counter = counter
+  end
+
   def string(base)
     @base = base
-    @counter = nil
 
     increment_counter! while yield(base_string)
     base_string
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 7611e83647c..0332bfa9371 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -194,6 +194,15 @@ class Issue < ActiveRecord::Base
     branches_with_iid - branches_with_merge_request
   end
 
+  def suggested_branch_name
+    return to_branch_name unless project.repository.branch_exists?(to_branch_name)
+
+    start_counting_from = 2
+    Uniquify.new(start_counting_from).string(-> (counter) { "#{to_branch_name}-#{counter}" }) do |suggested_branch_name|
+      project.repository.branch_exists?(suggested_branch_name)
+    end
+  end
+
   # Returns boolean if a related branch exists for the current issue
   # ignores merge requests branchs
   def has_related_branch?
@@ -248,11 +257,8 @@ class Issue < ActiveRecord::Base
     end
   end
 
-  def can_be_worked_on?(current_user)
-    !self.closed? &&
-      !self.project.forked? &&
-      self.related_branches(current_user).empty? &&
-      self.closed_by_merge_requests(current_user).empty?
+  def can_be_worked_on?
+    !self.closed? && !self.project.forked?
   end
 
   # Returns `true` if the current issue can be viewed by either a logged in User
diff --git a/app/models/user.rb b/app/models/user.rb
index 7a42d546b9c..b0668148972 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -947,10 +947,13 @@ class User < ActiveRecord::Base
   end
 
   def manageable_groups
-    union = Gitlab::SQL::Union.new([owned_groups.select(:id),
-                                    masters_groups.select(:id)])
-    arel_union = Arel::Nodes::SqlLiteral.new(union.to_sql)
-    owned_and_master_groups = Group.where(Group.arel_table[:id].in(arel_union))
+    union_sql = Gitlab::SQL::Union.new([owned_groups.select(:id), masters_groups.select(:id)]).to_sql
+
+    # Update this line to not use raw SQL when migrated to Rails 5.2.
+    # Either ActiveRecord or Arel constructions are fine.
+    # This was replaced with the raw SQL construction because of bugs in the arel gem.
+    # Bugs were fixed in arel 9.0.0 (Rails 5.2).
+    owned_and_master_groups = Group.where("namespaces.id IN (#{union_sql})") # rubocop:disable GitlabSecurity/SqlInjection
 
     Gitlab::GroupHierarchy.new(owned_and_master_groups).base_and_descendants
   end
diff --git a/app/serializers/entity_date_helper.rb b/app/serializers/entity_date_helper.rb
index 71d9a65fb58..464217123b4 100644
--- a/app/serializers/entity_date_helper.rb
+++ b/app/serializers/entity_date_helper.rb
@@ -1,5 +1,6 @@
 module EntityDateHelper
   include ActionView::Helpers::DateHelper
+  include ActionView::Helpers::TagHelper
 
   def interval_in_words(diff)
     return 'Not started' unless diff
@@ -34,4 +35,30 @@ module EntityDateHelper
 
     duration_hash
   end
+
+  # Generates an HTML-formatted string for remaining dates based on start_date and due_date
+  #
+  # It returns "Past due" for expired entities
+  # It returns "Upcoming" for upcoming entities
+  # If due date is provided, it returns "# days|weeks|months remaining|ago"
+  # If start date is provided and elapsed, with no due date, it returns "# days elapsed"
+  def remaining_days_in_words(entity)
+    if entity.try(:expired?)
+      content_tag(:strong, 'Past due')
+    elsif entity.try(:upcoming?)
+      content_tag(:strong, 'Upcoming')
+    elsif entity.due_date
+      is_upcoming = (entity.due_date - Date.today).to_i > 0
+      time_ago = time_ago_in_words(entity.due_date)
+      content = time_ago.gsub(/\d+/) { |match| "<strong>#{match}</strong>" }
+      content.slice!("about ")
+      content << " " + (is_upcoming ? _("remaining") : _("ago"))
+      content.html_safe
+    elsif entity.start_date && entity.start_date.past?
+      days    = entity.elapsed_days
+      content = content_tag(:strong, days)
+      content << " #{'day'.pluralize(days)} elapsed"
+      content.html_safe
+    end
+  end
 end
diff --git a/app/services/projects/create_from_template_service.rb b/app/services/projects/create_from_template_service.rb
index a549cfbabea..29b133cc466 100644
--- a/app/services/projects/create_from_template_service.rb
+++ b/app/services/projects/create_from_template_service.rb
@@ -8,9 +8,10 @@ module Projects
       template_name = params.delete(:template_name)
       file = Gitlab::ProjectTemplate.find(template_name).file
 
+      override_params = params.dup
       params[:file] = file
 
-      GitlabProjectsImportService.new(current_user, params).execute
+      GitlabProjectsImportService.new(current_user, params, override_params).execute
 
     ensure
       file&.close
diff --git a/app/views/projects/issues/_issue.html.haml b/app/views/projects/issues/_issue.html.haml
index 0c58dd60e2c..e27f5658e87 100644
--- a/app/views/projects/issues/_issue.html.haml
+++ b/app/views/projects/issues/_issue.html.haml
@@ -26,7 +26,7 @@
           - if issue.milestone
             %span.issuable-milestone.hidden-xs
               &nbsp;
-              = link_to project_issues_path(issue.project, milestone_title: issue.milestone.title), data: { html: 1, toggle: 'tooltip', title: issuable_milestone_tooltip_title(issue) } do
+              = link_to project_issues_path(issue.project, milestone_title: issue.milestone.title), data: { html: 1, toggle: 'tooltip', title: milestone_tooltip_due_date(issue.milestone) } do
                 = icon('clock-o')
                 = issue.milestone.title
           - if issue.due_date
diff --git a/app/views/projects/merge_requests/_merge_request.html.haml b/app/views/projects/merge_requests/_merge_request.html.haml
index a94267deeb2..027a9ff1416 100644
--- a/app/views/projects/merge_requests/_merge_request.html.haml
+++ b/app/views/projects/merge_requests/_merge_request.html.haml
@@ -23,7 +23,7 @@
         - if merge_request.milestone
           %span.issuable-milestone.hidden-xs
             &nbsp;
-            = link_to project_merge_requests_path(merge_request.project, milestone_title: merge_request.milestone.title), data: { html: 1, toggle: 'tooltip', title: issuable_milestone_tooltip_title(merge_request) } do
+            = link_to project_merge_requests_path(merge_request.project, milestone_title: merge_request.milestone.title), data: { html: 1, toggle: 'tooltip', title: milestone_tooltip_due_date(merge_request.milestone) } do
               = icon('clock-o')
               = merge_request.milestone.title
         - if merge_request.target_project.default_branch != merge_request.target_branch
diff --git a/app/views/shared/issuable/_sidebar.html.haml b/app/views/shared/issuable/_sidebar.html.haml
index aa883b9b1fa..093033775a9 100644
--- a/app/views/shared/issuable/_sidebar.html.haml
+++ b/app/views/shared/issuable/_sidebar.html.haml
@@ -7,7 +7,7 @@
       - if current_user
         %span.issuable-header-text.hide-collapsed.pull-left
           = _('Todo')
-      %a.gutter-toggle.pull-right.js-sidebar-toggle{ role: "button", href: "#", "aria-label" => "Toggle sidebar" }
+      %a.gutter-toggle.pull-right.js-sidebar-toggle.has-tooltip{ role: "button", href: "#", "aria-label" => "Toggle sidebar", title: sidebar_gutter_tooltip_text, data: { container: 'body', placement: 'left' } }
         = sidebar_gutter_toggle_icon
       - if current_user
         = render "shared/issuable/sidebar_todo", todo: todo, issuable: issuable
@@ -19,12 +19,11 @@
       .block.assignee
         = render "shared/issuable/sidebar_assignees", issuable: issuable, can_edit_issuable: can_edit_issuable, signed_in: current_user.present?
       .block.milestone
-        .sidebar-collapsed-icon
+        .sidebar-collapsed-icon.has-tooltip{ title: milestone_tooltip_title(issuable.milestone), data: { container: 'body', html: 1, placement: 'left' } }
           = icon('clock-o', 'aria-hidden': 'true')
           %span.milestone-title
             - if issuable.milestone
-              %span.has-tooltip{ title: "#{issuable.milestone.title}<br>#{milestone_tooltip_title(issuable.milestone)}", data: { container: 'body', html: 1, placement: 'left' } }
-                = issuable.milestone.title
+              = issuable.milestone.title
             - else
               = _('None')
         .title.hide-collapsed
@@ -34,7 +33,7 @@
             = link_to _('Edit'), '#', class: 'js-sidebar-dropdown-toggle edit-link pull-right'
         .value.hide-collapsed
           - if issuable.milestone
-            = link_to issuable.milestone.title, milestone_path(issuable.milestone), class: "bold has-tooltip", title: milestone_tooltip_title(issuable.milestone), data: { container: "body", html: 1 }
+            = link_to issuable.milestone.title, milestone_path(issuable.milestone), class: "bold has-tooltip", title: milestone_tooltip_due_date(issuable.milestone), data: { container: "body", html: 1 }
           - else
             %span.no-value
               = _('None')
@@ -50,7 +49,7 @@
             = icon('spinner spin', 'aria-hidden': 'true')
       - if issuable.has_attribute?(:due_date)
         .block.due_date
-          .sidebar-collapsed-icon
+          .sidebar-collapsed-icon.has-tooltip{ data: { placement: 'left', container: 'body', html: 1 }, title: sidebar_due_date_tooltip_label(issuable) }
             = icon('calendar', 'aria-hidden': 'true')
             %span.js-due-date-sidebar-value
               = issuable.due_date.try(:to_s, :medium) || 'None'
diff --git a/app/views/shared/issuable/_sidebar_assignees.html.haml b/app/views/shared/issuable/_sidebar_assignees.html.haml
index 304df38a096..21006a76b28 100644
--- a/app/views/shared/issuable/_sidebar_assignees.html.haml
+++ b/app/views/shared/issuable/_sidebar_assignees.html.haml
@@ -4,7 +4,7 @@
       = _('Assignee')
       = icon('spinner spin')
 - else
-  .sidebar-collapsed-icon.sidebar-collapsed-user{ data: { toggle: "tooltip", placement: "left", container: "body" }, title: (issuable.assignee.name if issuable.assignee) }
+  .sidebar-collapsed-icon.sidebar-collapsed-user{ data: { toggle: "tooltip", placement: "left", container: "body" }, title: sidebar_assignee_tooltip_label(issuable) }
     - if issuable.assignee
       = link_to_member(@project, issuable.assignee, size: 24)
     - else
diff --git a/app/views/shared/issuable/_sidebar_todo.html.haml b/app/views/shared/issuable/_sidebar_todo.html.haml
index b77e104c072..74327fb1ba8 100644
--- a/app/views/shared/issuable/_sidebar_todo.html.haml
+++ b/app/views/shared/issuable/_sidebar_todo.html.haml
@@ -1,11 +1,11 @@
 - is_collapsed = local_assigns.fetch(:is_collapsed, false)
-- mark_content = is_collapsed ? icon('check-square', class: 'todo-undone') : _('Mark done')
+- mark_content = is_collapsed ? icon('check-square', class: 'todo-undone') : _('Mark todo as done')
 - todo_content = is_collapsed ? icon('plus-square') : _('Add todo')
 
 %button.issuable-todo-btn.js-issuable-todo{ type: 'button',
   class: (is_collapsed ? 'btn-blank sidebar-collapsed-icon dont-change-state has-tooltip' : 'btn btn-default issuable-header-btn pull-right'),
-  title: (todo.nil? ? _('Add todo') : _('Mark done')),
-  'aria-label' => (todo.nil? ? _('Add todo') : _('Mark done')),
+  title: (todo.nil? ? _('Add todo') : _('Mark todo as done')),
+  'aria-label' => (todo.nil? ? _('Add todo') : _('Mark todo as done')),
   data: issuable_todo_button_data(issuable, todo, is_collapsed) }
   %span.issuable-todo-inner.js-issuable-todo-inner<
     - if todo
diff --git a/app/views/shared/issuable/form/_merge_request_assignee.html.haml b/app/views/shared/issuable/form/_merge_request_assignee.html.haml
index bf8613b0f0d..d7740eddcca 100644
--- a/app/views/shared/issuable/form/_merge_request_assignee.html.haml
+++ b/app/views/shared/issuable/form/_merge_request_assignee.html.haml
@@ -1,6 +1,6 @@
 - merge_request = issuable
 .block.assignee
-  .sidebar-collapsed-icon.sidebar-collapsed-user{ data: { toggle: "tooltip", placement: "left", container: "body" }, title: (merge_request.assignee.name if merge_request.assignee) }
+  .sidebar-collapsed-icon.sidebar-collapsed-user{ data: { toggle: "tooltip", placement: "left", container: "body" }, title: sidebar_assignee_tooltip_label(issuable) }
     - if merge_request.assignee
       = link_to_member(@project, merge_request.assignee, size: 24)
     - else
diff --git a/app/views/shared/milestones/_sidebar.html.haml b/app/views/shared/milestones/_sidebar.html.haml
index ee134480705..8e9a1b56bb8 100644
--- a/app/views/shared/milestones/_sidebar.html.haml
+++ b/app/views/shared/milestones/_sidebar.html.haml
@@ -4,12 +4,8 @@
 %aside.right-sidebar.js-right-sidebar{ data: { "offset-top" => affix_offset, "spy" => "affix", "always-show-toggle" => true }, class: sidebar_gutter_collapsed_class, 'aria-live' => 'polite' }
   .issuable-sidebar.milestone-sidebar
     .block.milestone-progress.issuable-sidebar-header
-      %a.gutter-toggle.pull-right.js-sidebar-toggle{ role: "button", href: "#", "aria-label" => "Toggle sidebar" }
+      %a.gutter-toggle.pull-right.js-sidebar-toggle.has-tooltip{ role: "button", href: "#", "aria-label" => "Toggle sidebar", title: sidebar_gutter_tooltip_text, data: { container: 'body', placement: 'left' } }
         = sidebar_gutter_toggle_icon
-
-      .sidebar-collapsed-icon
-        %span== #{milestone.percent_complete(current_user)}%
-        = milestone_progress_bar(milestone)
       .title.hide-collapsed
         %strong.bold== #{milestone.percent_complete(current_user)}%
         %span.hide-collapsed
@@ -17,6 +13,11 @@
       .value.hide-collapsed
         = milestone_progress_bar(milestone)
 
+    .block.milestone-progress.hide-expanded
+      .sidebar-collapsed-icon.has-tooltip{ title: milestone_progress_tooltip_text(milestone), data: { container: 'body', html: 1, placement: 'left' } }
+        %span== #{milestone.percent_complete(current_user)}%
+        = milestone_progress_bar(milestone)
+
     .block.start_date.hide-collapsed
       .title
         Start date
@@ -35,19 +36,25 @@
         %span.collapsed-milestone-date
           - if milestone.start_date && milestone.due_date
             - if milestone.start_date.year == milestone.due_date.year
-              .milestone-date= milestone.start_date.strftime('%b %-d')
+              .milestone-date.has-tooltip{ title: milestone_time_for(milestone.start_date, :start), data: { container: 'body', html: 1, placement: 'left' } }
+                = milestone.start_date.strftime('%b %-d')
             - else
-              .milestone-date= milestone.start_date.strftime('%b %-d %Y')
+              .milestone-date.has-tooltip{ title: milestone_time_for(milestone.start_date, :start), data: { container: 'body', html: 1, placement: 'left' } }
+                = milestone.start_date.strftime('%b %-d %Y')
             .date-separator -
-            .due_date= milestone.due_date.strftime('%b %-d %Y')
+            .due_date.has-tooltip{ title: milestone_time_for(milestone.due_date, :end), data: { container: 'body', html: 1, placement: 'left' } }
+              = milestone.due_date.strftime('%b %-d %Y')
           - elsif milestone.start_date
             From
-            .milestone-date= milestone.start_date.strftime('%b %-d %Y')
+            .milestone-date.has-tooltip{ title: milestone_time_for(milestone.start_date, :start), data: { container: 'body', html: 1, placement: 'left' } }
+              = milestone.start_date.strftime('%b %-d %Y')
           - elsif milestone.due_date
             Until
-            .milestone-date= milestone.due_date.strftime('%b %-d %Y')
+            .milestone-date.has-tooltip{ title: milestone_time_for(milestone.due_date, :end), data: { container: 'body', html: 1, placement: 'left' } }
+              = milestone.due_date.strftime('%b %-d %Y')
           - else
-            None
+            .has-tooltip{ title: milestone_time_for(milestone.start_date, :start), data: { container: 'body', html: 1, placement: 'left' } }
+              None
       .title.hide-collapsed
         Due date
         - if @project && can?(current_user, :admin_milestone, @project)
@@ -58,14 +65,14 @@
             %span.bold= milestone.due_date.to_s(:medium)
           - else
             %span.no-value No due date
-        - remaining_days = milestone_remaining_days(milestone)
+        - remaining_days = remaining_days_in_words(milestone)
         - if remaining_days.present?
           = surround '(', ')' do
             %span.remaining-days= remaining_days
 
     - if !project || can?(current_user, :read_issue, project)
       .block.issues
-        .sidebar-collapsed-icon
+        .sidebar-collapsed-icon.has-tooltip{ title: milestone_issues_tooltip_text(milestone), data: { container: 'body', html: 1, placement: 'left' } }
           %strong
             = custom_icon('issues')
           %span= milestone.issues_visible_to_user(current_user).count
@@ -93,7 +100,7 @@
           = icon('spinner spin')
 
     .block.merge-requests
-      .sidebar-collapsed-icon
+      .sidebar-collapsed-icon.has-tooltip{ title: milestone_merge_requests_tooltip_text(milestone), data: { container: 'body', html: 1, placement: 'left' } }
         %strong
           = custom_icon('mr_bold')
         %span= milestone.merge_requests.count