Merge branch 'ccr/wip_filter' into 'master'

#13650 added wip search functionality and tests

See merge request gitlab-org/gitlab-ce!18119

22 files changed, 300 insertions, 56 deletions

diff --git a/app/assets/javascripts/filtered_search/dropdown_hint.js b/app/assets/javascripts/filtered_search/dropdown_hint.js
index 8aecf9725e6..c568f4e4ebf 100644
--- a/app/assets/javascripts/filtered_search/dropdown_hint.js
+++ b/app/assets/javascripts/filtered_search/dropdown_hint.js
@@ -51,7 +51,11 @@ export default class DropdownHint extends FilteredSearchDropdown {
             FilteredSearchVisualTokens.addSearchVisualToken(searchTerms.join(' '));
           }
 
-          FilteredSearchDropdownManager.addWordToInput(token.replace(':', ''), '', false, this.container);
+          const key = token.replace(':', '');
+          const { uppercaseTokenName } = this.tokenKeys.searchByKey(key);
+          FilteredSearchDropdownManager.addWordToInput(key, '', false, {
+            uppercaseTokenName,
+          });
         }
         this.dismissDropdown();
         this.dispatchInputEvent();
diff --git a/app/assets/javascripts/filtered_search/dropdown_utils.js b/app/assets/javascripts/filtered_search/dropdown_utils.js
index 27fff488603..6da6ca10008 100644
--- a/app/assets/javascripts/filtered_search/dropdown_utils.js
+++ b/app/assets/javascripts/filtered_search/dropdown_utils.js
@@ -143,7 +143,9 @@ export default class DropdownUtils {
     const dataValue = selected.getAttribute('data-value');
 
     if (dataValue) {
-      FilteredSearchDropdownManager.addWordToInput(filter, dataValue, true);
+      FilteredSearchDropdownManager.addWordToInput(filter, dataValue, true, {
+        capitalizeTokenValue: selected.hasAttribute('data-capitalize'),
+      });
     }
 
     // Return boolean based on whether it was set
diff --git a/app/assets/javascripts/filtered_search/filtered_search_dropdown_manager.js b/app/assets/javascripts/filtered_search/filtered_search_dropdown_manager.js
index 207616b9de2..cd3d532c958 100644
--- a/app/assets/javascripts/filtered_search/filtered_search_dropdown_manager.js
+++ b/app/assets/javascripts/filtered_search/filtered_search_dropdown_manager.js
@@ -91,6 +91,11 @@ export default class FilteredSearchDropdownManager {
         gl: DropdownEmoji,
         element: this.container.querySelector('#js-dropdown-my-reaction'),
       },
+      wip: {
+        reference: null,
+        gl: DropdownNonUser,
+        element: this.container.querySelector('#js-dropdown-wip'),
+      },
       status: {
         reference: null,
         gl: NullDropdown,
@@ -136,10 +141,16 @@ export default class FilteredSearchDropdownManager {
     return endpoint;
   }
 
-  static addWordToInput(tokenName, tokenValue = '', clicked = false) {
+  static addWordToInput(tokenName, tokenValue = '', clicked = false, options = {}) {
+    const {
+      uppercaseTokenName = false,
+      capitalizeTokenValue = false,
+    } = options;
     const input = FilteredSearchContainer.container.querySelector('.filtered-search');
-
-    FilteredSearchVisualTokens.addFilterVisualToken(tokenName, tokenValue);
+    FilteredSearchVisualTokens.addFilterVisualToken(tokenName, tokenValue, {
+      uppercaseTokenName,
+      capitalizeTokenValue,
+    });
     input.value = '';
 
     if (clicked) {
diff --git a/app/assets/javascripts/filtered_search/filtered_search_manager.js b/app/assets/javascripts/filtered_search/filtered_search_manager.js
index d25f6f95b22..54533ebb70d 100644
--- a/app/assets/javascripts/filtered_search/filtered_search_manager.js
+++ b/app/assets/javascripts/filtered_search/filtered_search_manager.js
@@ -405,7 +405,10 @@ export default class FilteredSearchManager {
     if (isLastVisualTokenValid) {
       tokens.forEach((t) => {
         input.value = input.value.replace(`${t.key}:${t.symbol}${t.value}`, '');
-        FilteredSearchVisualTokens.addFilterVisualToken(t.key, `${t.symbol}${t.value}`);
+        FilteredSearchVisualTokens.addFilterVisualToken(t.key, `${t.symbol}${t.value}`, {
+          uppercaseTokenName: this.filteredSearchTokenKeys.shouldUppercaseTokenName(t.key),
+          capitalizeTokenValue: this.filteredSearchTokenKeys.shouldCapitalizeTokenValue(t.key),
+        });
       });
 
       const fragments = searchToken.split(':');
@@ -421,7 +424,10 @@ export default class FilteredSearchManager {
           FilteredSearchVisualTokens.addSearchVisualToken(searchTerms);
         }
 
-        FilteredSearchVisualTokens.addFilterVisualToken(tokenKey);
+        FilteredSearchVisualTokens.addFilterVisualToken(tokenKey, null, {
+          uppercaseTokenName: this.filteredSearchTokenKeys.shouldUppercaseTokenName(tokenKey),
+          capitalizeTokenValue: this.filteredSearchTokenKeys.shouldCapitalizeTokenValue(tokenKey),
+        });
         input.value = input.value.replace(`${tokenKey}:`, '');
       }
     } else {
@@ -429,7 +435,10 @@ export default class FilteredSearchManager {
       const valueCompletedRegex = /([~%@]{0,1}".+")|([~%@]{0,1}'.+')|^((?![~%@]')(?![~%@]")(?!')(?!")).*/g;
 
       if (searchToken.match(valueCompletedRegex) && input.value[input.value.length - 1] === ' ') {
-        FilteredSearchVisualTokens.addFilterVisualToken(searchToken);
+        const tokenKey = FilteredSearchVisualTokens.getLastTokenPartial();
+        FilteredSearchVisualTokens.addFilterVisualToken(searchToken, null, {
+          capitalizeTokenValue: this.filteredSearchTokenKeys.shouldCapitalizeTokenValue(tokenKey),
+        });
 
         // Trim the last space as seen in the if statement above
         input.value = input.value.replace(searchToken, '').trim();
@@ -480,7 +489,7 @@ export default class FilteredSearchManager {
         FilteredSearchVisualTokens.addFilterVisualToken(
           condition.tokenKey,
           condition.value,
-          canEdit,
+          { canEdit },
         );
       } else {
         // Sanitize value since URL converts spaces into +
@@ -506,10 +515,15 @@ export default class FilteredSearchManager {
 
           hasFilteredSearch = true;
           const canEdit = this.canEdit && this.canEdit(sanitizedKey, sanitizedValue);
+          const { uppercaseTokenName, capitalizeTokenValue } = match;
           FilteredSearchVisualTokens.addFilterVisualToken(
             sanitizedKey,
             `${symbol}${quotationsToUse}${sanitizedValue}${quotationsToUse}`,
-            canEdit,
+            {
+              canEdit,
+              uppercaseTokenName,
+              capitalizeTokenValue,
+            },
           );
         } else if (!match && keyParam === 'assignee_id') {
           const id = parseInt(value, 10);
@@ -517,7 +531,7 @@ export default class FilteredSearchManager {
             hasFilteredSearch = true;
             const tokenName = 'assignee';
             const canEdit = this.canEdit && this.canEdit(tokenName);
-            FilteredSearchVisualTokens.addFilterVisualToken(tokenName, `@${usernameParams[id]}`, canEdit);
+            FilteredSearchVisualTokens.addFilterVisualToken(tokenName, `@${usernameParams[id]}`, { canEdit });
           }
         } else if (!match && keyParam === 'author_id') {
           const id = parseInt(value, 10);
@@ -525,7 +539,7 @@ export default class FilteredSearchManager {
             hasFilteredSearch = true;
             const tokenName = 'author';
             const canEdit = this.canEdit && this.canEdit(tokenName);
-            FilteredSearchVisualTokens.addFilterVisualToken(tokenName, `@${usernameParams[id]}`, canEdit);
+            FilteredSearchVisualTokens.addFilterVisualToken(tokenName, `@${usernameParams[id]}`, { canEdit });
           }
         } else if (!match && keyParam === 'search') {
           hasFilteredSearch = true;
@@ -561,15 +575,17 @@ export default class FilteredSearchManager {
 
     this.saveCurrentSearchQuery();
 
-    const { tokens, searchToken }
-      = this.tokenizer.processTokens(searchQuery, this.filteredSearchTokenKeys.getKeys());
+    const tokenKeys = this.filteredSearchTokenKeys.getKeys();
+    const { tokens, searchToken } = this.tokenizer.processTokens(searchQuery, tokenKeys);
     const currentState = state || getParameterByName('state') || 'opened';
     paths.push(`state=${currentState}`);
 
     tokens.forEach((token) => {
       const condition = this.filteredSearchTokenKeys
         .searchByConditionKeyValue(token.key, token.value.toLowerCase());
-      const { param } = this.filteredSearchTokenKeys.searchByKey(token.key) || {};
+      const tokenConfig = this.filteredSearchTokenKeys.searchByKey(token.key) || {};
+      const { param } = tokenConfig;
+
       // Replace hyphen with underscore to use as request parameter
       // e.g. 'my-reaction' => 'my_reaction'
       const underscoredKey = token.key.replace('-', '_');
@@ -581,6 +597,10 @@ export default class FilteredSearchManager {
       } else {
         let tokenValue = token.value;
 
+        if (tokenConfig.lowercaseValueOnSubmit) {
+          tokenValue = tokenValue.toLowerCase();
+        }
+
         if ((tokenValue[0] === '\'' && tokenValue[tokenValue.length - 1] === '\'') ||
           (tokenValue[0] === '"' && tokenValue[tokenValue.length - 1] === '"')) {
           tokenValue = tokenValue.slice(1, tokenValue.length - 1);
diff --git a/app/assets/javascripts/filtered_search/filtered_search_token_keys.js b/app/assets/javascripts/filtered_search/filtered_search_token_keys.js
index 5d131b396a0..a09ad3e4758 100644
--- a/app/assets/javascripts/filtered_search/filtered_search_token_keys.js
+++ b/app/assets/javascripts/filtered_search/filtered_search_token_keys.js
@@ -23,6 +23,16 @@ export default class FilteredSearchTokenKeys {
     return this.conditions;
   }
 
+  shouldUppercaseTokenName(tokenKey) {
+    const token = this.searchByKey(tokenKey.toLowerCase());
+    return token && token.uppercaseTokenName;
+  }
+
+  shouldCapitalizeTokenValue(tokenKey) {
+    const token = this.searchByKey(tokenKey.toLowerCase());
+    return token && token.capitalizeTokenValue;
+  }
+
   searchByKey(key) {
     return this.tokenKeys.find(tokenKey => tokenKey.key === key) || null;
   }
@@ -55,4 +65,21 @@ export default class FilteredSearchTokenKeys {
     return this.conditions
       .find(condition => condition.tokenKey === key && condition.value === value) || null;
   }
+
+  addExtraTokensForMergeRequests() {
+    const wipToken = {
+      key: 'wip',
+      type: 'string',
+      param: '',
+      symbol: '',
+      icon: 'admin',
+      tag: 'Yes or No',
+      lowercaseValueOnSubmit: true,
+      uppercaseTokenName: true,
+      capitalizeTokenValue: true,
+    };
+
+    this.tokenKeys.push(wipToken);
+    this.tokenKeysWithAlternative.push(wipToken);
+  }
 }
diff --git a/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js b/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js
index 56fe1ab4e90..0854c1822fb 100644
--- a/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js
+++ b/app/assets/javascripts/filtered_search/filtered_search_visual_tokens.js
@@ -55,12 +55,18 @@ export default class FilteredSearchVisualTokens {
     }
   }
 
-  static createVisualTokenElementHTML(canEdit = true) {
+  static createVisualTokenElementHTML(options = {}) {
+    const {
+      canEdit = true,
+      uppercaseTokenName = false,
+      capitalizeTokenValue = false,
+    } = options;
+
     return `
       <div class="${canEdit ? 'selectable' : 'hidden'}" role="button">
-        <div class="name"></div>
+        <div class="${uppercaseTokenName ? 'text-uppercase' : ''} name"></div>
         <div class="value-container">
-          <div class="value"></div>
+          <div class="${capitalizeTokenValue ? 'text-capitalize' : ''} value"></div>
           <div class="remove-token" role="button">
             <i class="fa fa-close"></i>
           </div>
@@ -182,16 +188,26 @@ export default class FilteredSearchVisualTokens {
     }
   }
 
-  static addVisualTokenElement(name, value, isSearchTerm, canEdit) {
+  static addVisualTokenElement(name, value, options = {}) {
+    const {
+      isSearchTerm = false,
+      canEdit,
+      uppercaseTokenName,
+      capitalizeTokenValue,
+    } = options;
     const li = document.createElement('li');
     li.classList.add('js-visual-token');
     li.classList.add(isSearchTerm ? 'filtered-search-term' : 'filtered-search-token');
 
     if (value) {
-      li.innerHTML = FilteredSearchVisualTokens.createVisualTokenElementHTML(canEdit);
+      li.innerHTML = FilteredSearchVisualTokens.createVisualTokenElementHTML({
+        canEdit,
+        uppercaseTokenName,
+        capitalizeTokenValue,
+      });
       FilteredSearchVisualTokens.renderVisualTokenValue(li, name, value);
     } else {
-      li.innerHTML = '<div class="name"></div>';
+      li.innerHTML = `<div class="${uppercaseTokenName ? 'text-uppercase' : ''} name"></div>`;
     }
     li.querySelector('.name').innerText = name;
 
@@ -212,20 +228,32 @@ export default class FilteredSearchVisualTokens {
     }
   }
 
-  static addFilterVisualToken(tokenName, tokenValue, canEdit) {
+  static addFilterVisualToken(tokenName, tokenValue, {
+    canEdit,
+    uppercaseTokenName = false,
+    capitalizeTokenValue = false,
+  } = {}) {
     const { lastVisualToken, isLastVisualTokenValid }
       = FilteredSearchVisualTokens.getLastVisualTokenBeforeInput();
     const { addVisualTokenElement } = FilteredSearchVisualTokens;
 
     if (isLastVisualTokenValid) {
-      addVisualTokenElement(tokenName, tokenValue, false, canEdit);
+      addVisualTokenElement(tokenName, tokenValue, {
+        canEdit,
+        uppercaseTokenName,
+        capitalizeTokenValue,
+      });
     } else {
       const previousTokenName = lastVisualToken.querySelector('.name').innerText;
       const tokensContainer = FilteredSearchContainer.container.querySelector('.tokens-container');
       tokensContainer.removeChild(lastVisualToken);
 
       const value = tokenValue || tokenName;
-      addVisualTokenElement(previousTokenName, value, false, canEdit);
+      addVisualTokenElement(previousTokenName, value, {
+        canEdit,
+        uppercaseTokenName,
+        capitalizeTokenValue,
+      });
     }
   }
 
@@ -235,7 +263,9 @@ export default class FilteredSearchVisualTokens {
     if (lastVisualToken && lastVisualToken.classList.contains('filtered-search-term')) {
       lastVisualToken.querySelector('.name').innerText += ` ${searchTerm}`;
     } else {
-      FilteredSearchVisualTokens.addVisualTokenElement(searchTerm, null, true);
+      FilteredSearchVisualTokens.addVisualTokenElement(searchTerm, null, {
+        isSearchTerm: true,
+      });
     }
   }
 
@@ -306,7 +336,9 @@ export default class FilteredSearchVisualTokens {
     let value;
 
     if (token.classList.contains('filtered-search-token')) {
-      FilteredSearchVisualTokens.addFilterVisualToken(nameElement.innerText);
+      FilteredSearchVisualTokens.addFilterVisualToken(nameElement.innerText, null, {
+        uppercaseTokenName: nameElement.classList.contains('text-uppercase'),
+      });
 
       const valueContainerElement = token.querySelector('.value-container');
       value = valueContainerElement.dataset.originalValue;
diff --git a/app/assets/javascripts/pages/groups/merge_requests/index.js b/app/assets/javascripts/pages/groups/merge_requests/index.js
index b798a254459..339ce67438a 100644
--- a/app/assets/javascripts/pages/groups/merge_requests/index.js
+++ b/app/assets/javascripts/pages/groups/merge_requests/index.js
@@ -4,6 +4,8 @@ import IssuableFilteredSearchTokenKeys from '~/filtered_search/issuable_filtered
 import { FILTERED_SEARCH } from '~/pages/constants';
 
 document.addEventListener('DOMContentLoaded', () => {
+  IssuableFilteredSearchTokenKeys.addExtraTokensForMergeRequests();
+
   initFilteredSearch({
     page: FILTERED_SEARCH.MERGE_REQUESTS,
     isGroupDecendent: true,
diff --git a/app/assets/javascripts/pages/projects/merge_requests/index/index.js b/app/assets/javascripts/pages/projects/merge_requests/index/index.js
index 3647048a872..ec39db12e74 100644
--- a/app/assets/javascripts/pages/projects/merge_requests/index/index.js
+++ b/app/assets/javascripts/pages/projects/merge_requests/index/index.js
@@ -7,10 +7,13 @@ import { FILTERED_SEARCH } from '~/pages/constants';
 import { ISSUABLE_INDEX } from '~/pages/projects/constants';
 
 document.addEventListener('DOMContentLoaded', () => {
+  IssuableFilteredSearchTokenKeys.addExtraTokensForMergeRequests();
+
   initFilteredSearch({
     page: FILTERED_SEARCH.MERGE_REQUESTS,
     filteredSearchTokenKeys: IssuableFilteredSearchTokenKeys,
   });
+
   new IssuableIndex(ISSUABLE_INDEX.MERGE_REQUEST); // eslint-disable-line no-new
   new ShortcutsNavigation(); // eslint-disable-line no-new
   new UsersSelect(); // eslint-disable-line no-new
diff --git a/app/finders/merge_requests_finder.rb b/app/finders/merge_requests_finder.rb
index b698a3c7b09..50c051c3aa1 100644
--- a/app/finders/merge_requests_finder.rb
+++ b/app/finders/merge_requests_finder.rb
@@ -27,13 +27,17 @@
 #     updated_before: datetime
 #
 class MergeRequestsFinder < IssuableFinder
+  def self.scalar_params
+    @scalar_params ||= super + [:wip]
+  end
+
   def klass
     MergeRequest
   end
 
   def filter_items(_items)
     items = by_source_branch(super)
-
+    items = by_wip(items)
     by_target_branch(items)
   end
 
@@ -61,5 +65,24 @@ class MergeRequestsFinder < IssuableFinder
 
     items.where(target_branch: target_branch)
   end
-  # rubocop: enable CodeReuse/ActiveRecord
+
+  def item_project_ids(items)
+    items&.reorder(nil)&.select(:target_project_id)
+  end
+
+  def by_wip(items)
+    if params[:wip] == 'yes'
+      items.where(wip_match(items.arel_table))
+    elsif params[:wip] == 'no'
+      items.where.not(wip_match(items.arel_table))
+    else
+      items
+    end
+  end
+
+  def wip_match(table)
+    table[:title].matches('WIP:%')
+        .or(table[:title].matches('WIP %'))
+        .or(table[:title].matches('[WIP]%'))
+  end
 end
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 0481a4a3d28..6559f94a696 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -261,7 +261,7 @@ class MergeRequest < ActiveRecord::Base
     end
   end
 
-  WIP_REGEX = /\A\s*(\[WIP\]\s*|WIP:\s*|WIP\s+)+\s*/i.freeze
+  WIP_REGEX = /\A*(\[WIP\]\s*|WIP:\s*|WIP\s+)+\s*/i.freeze
 
   def self.work_in_progress?(title)
     !!(title =~ WIP_REGEX)
diff --git a/app/views/shared/issuable/_search_bar.html.haml b/app/views/shared/issuable/_search_bar.html.haml
index 659e03fd67d..c4d177361e7 100644
--- a/app/views/shared/issuable/_search_bar.html.haml
+++ b/app/views/shared/issuable/_search_bar.html.haml
@@ -33,13 +33,13 @@
             #js-dropdown-hint.filtered-search-input-dropdown-menu.dropdown-menu.hint-dropdown
               %ul{ data: { dropdown: true } }
                 %li.filter-dropdown-item{ data: { action: 'submit' } }
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     = sprite_icon('search')
                     %span
                       Press Enter or click to search
               %ul.filter-dropdown{ data: { dynamic: true, dropdown: true } }
                 %li.filter-dropdown-item
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     -# Encapsulate static class name `{{icon}}` inside #{} to bypass
                     -# haml lint's ClassAttributeWithStaticValue
                     %svg
@@ -60,7 +60,7 @@
             #js-dropdown-assignee.filtered-search-input-dropdown-menu.dropdown-menu
               %ul{ data: { dropdown: true } }
                 %li.filter-dropdown-item{ data: { value: 'none' } }
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     No Assignee
                 %li.divider.droplab-item-ignore
                 - if current_user
@@ -73,38 +73,46 @@
             #js-dropdown-milestone.filtered-search-input-dropdown-menu.dropdown-menu
               %ul{ data: { dropdown: true } }
                 %li.filter-dropdown-item{ data: { value: 'none' } }
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     No Milestone
                 %li.filter-dropdown-item{ data: { value: 'upcoming' } }
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     Upcoming
                 %li.filter-dropdown-item{ 'data-value' => 'started' }
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     Started
                 %li.divider.droplab-item-ignore
               %ul.filter-dropdown{ data: { dynamic: true, dropdown: true } }
                 %li.filter-dropdown-item
-                  %button.btn.btn-link.js-data-value
+                  %button.btn.btn-link.js-data-value{ type: 'button' }
                     {{title}}
             #js-dropdown-label.filtered-search-input-dropdown-menu.dropdown-menu
               %ul{ data: { dropdown: true } }
                 %li.filter-dropdown-item{ data: { value: 'none' } }
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     No Label
                 %li.divider.droplab-item-ignore
               %ul.filter-dropdown{ data: { dynamic: true, dropdown: true } }
                 %li.filter-dropdown-item
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     %span.dropdown-label-box{ style: 'background: {{color}}' }
                     %span.label-title.js-data-value
                       {{title}}
             #js-dropdown-my-reaction.filtered-search-input-dropdown-menu.dropdown-menu
               %ul.filter-dropdown{ data: { dynamic: true, dropdown: true } }
                 %li.filter-dropdown-item
-                  %button.btn.btn-link
+                  %button.btn.btn-link{ type: 'button' }
                     %gl-emoji
                     %span.js-data-value.prepend-left-10
                       {{name}}
+            #js-dropdown-wip.filtered-search-input-dropdown-menu.dropdown-menu
+              %ul.filter-dropdown{ data: { dropdown: true } }
+                %li.filter-dropdown-item{ data: { value: 'yes', capitalize: true } }
+                  %button.btn.btn-link{ type: 'button' }
+                    = _('Yes')
+                %li.filter-dropdown-item{ data: { value: 'no', capitalize: true } }
+                  %button.btn.btn-link{ type: 'button' }
+                    = _('No')
 
             = render_if_exists 'shared/issuable/filter_weight', type: type
 
diff --git a/changelogs/unreleased/ccr-wip_filter.yml b/changelogs/unreleased/ccr-wip_filter.yml
new file mode 100644
index 00000000000..07d85ec02ae
--- /dev/null
+++ b/changelogs/unreleased/ccr-wip_filter.yml
@@ -0,0 +1,5 @@
+---
+title: Added search functionality for Work In Progress (WIP) merge requests
+merge_request: 18119
+author: Chantal Rollison
+type: added
diff --git a/doc/api/merge_requests.md b/doc/api/merge_requests.md
index 4c099581f07..b37e7698ab4 100644
--- a/doc/api/merge_requests.md
+++ b/doc/api/merge_requests.md
@@ -47,6 +47,7 @@ Parameters:
 | `source_branch`     | string   | no       | Return merge requests with the given source branch                                                                     |
 | `target_branch`     | string   | no       | Return merge requests with the given target branch                                                                     |
 | `search`            | string   | no       | Search merge requests against their `title` and `description`                                                          |
+| `wip`            | string   | no       | Filter merge requests against their `wip` status. `yes` to return *only* WIP merge requests, `no` to return *non* WIP merge requests                                                        |
 
 ```json
 [
diff --git a/doc/user/project/merge_requests/img/filter_wip_merge_requests.png b/doc/user/project/merge_requests/img/filter_wip_merge_requests.png
new file mode 100644
index 00000000000..40913718385
--- /dev/null
+++ b/doc/user/project/merge_requests/img/filter_wip_merge_requests.png
diff --git a/doc/user/project/merge_requests/work_in_progress_merge_requests.md b/doc/user/project/merge_requests/work_in_progress_merge_requests.md
index f01da06fa6e..66ac7740157 100644
--- a/doc/user/project/merge_requests/work_in_progress_merge_requests.md
+++ b/doc/user/project/merge_requests/work_in_progress_merge_requests.md
@@ -7,7 +7,7 @@ have been marked a **Work In Progress**.
 ![Blocked Accept Button](img/wip_blocked_accept_button.png)
 
 To mark a merge request a Work In Progress, simply start its title with `[WIP]`
-or `WIP:`. As an alternative, you're also able to do it by sending a commit 
+or `WIP:`. As an alternative, you're also able to do it by sending a commit
 with its title starting with `wip` or `WIP` to the merge request's source branch.
 
 ![Mark as WIP](img/wip_mark_as_wip.png)
@@ -15,4 +15,11 @@ with its title starting with `wip` or `WIP` to the merge request's source branch
 To allow a Work In Progress merge request to be accepted again when it's ready,
 simply remove the `WIP` prefix.
 
-![Unark as WIP](img/wip_unmark_as_wip.png)
+![Unmark as WIP](img/wip_unmark_as_wip.png)
+
+## Filtering merge requests with WIP Status
+
+To filter merge requests with the `WIP` status, you can type `wip`
+and select the value for your filter from the merge request search input.
+
+![Filter WIP MRs](img/filter_wip_merge_requests.png)
diff --git a/lib/api/merge_requests.rb b/lib/api/merge_requests.rb
index 764905ca00f..440d94ae186 100644
--- a/lib/api/merge_requests.rb
+++ b/lib/api/merge_requests.rb
@@ -33,7 +33,6 @@ module API
       # rubocop: disable CodeReuse/ActiveRecord
       def find_merge_requests(args = {})
         args = declared_params.merge(args)
-
         args[:milestone_title] = args.delete(:milestone)
         args[:label_name] = args.delete(:labels)
         args[:scope] = args[:scope].underscore if args[:scope]
@@ -97,6 +96,7 @@ module API
         optional :source_branch, type: String, desc: 'Return merge requests with the given source branch'
         optional :target_branch, type: String, desc: 'Return merge requests with the given target branch'
         optional :search, type: String, desc: 'Search merge requests for text present in the title or description'
+        optional :wip, type: String, values: %w[yes no], desc: 'Search merge requests for WIP in the title'
         use :pagination
       end
     end
diff --git a/spec/features/issues/filtered_search/dropdown_hint_spec.rb b/spec/features/issues/filtered_search/dropdown_hint_spec.rb
index b99c5a7f4e3..0e296ab2109 100644
--- a/spec/features/issues/filtered_search/dropdown_hint_spec.rb
+++ b/spec/features/issues/filtered_search/dropdown_hint_spec.rb
@@ -15,6 +15,7 @@ describe 'Dropdown hint', :js do
   before do
     project.add_maintainer(user)
     create(:issue, project: project)
+    create(:merge_request, source_project: project, target_project: project)
   end
 
   context 'when user not logged in' do
@@ -224,4 +225,21 @@ describe 'Dropdown hint', :js do
       end
     end
   end
+
+  context 'merge request page' do
+    before do
+      sign_in(user)
+      visit project_merge_requests_path(project)
+      filtered_search.click
+    end
+
+    it 'shows the WIP menu item and opens the WIP options dropdown' do
+      click_hint('wip')
+
+      expect(page).to have_css(js_dropdown_hint, visible: false)
+      expect(page).to have_css('#js-dropdown-wip', visible: true)
+      expect_tokens([{ name: 'wip' }])
+      expect_filtered_search_input_empty
+    end
+  end
 end
diff --git a/spec/finders/merge_requests_finder_spec.rb b/spec/finders/merge_requests_finder_spec.rb
index 35d0eeda8f6..33d01697c75 100644
--- a/spec/finders/merge_requests_finder_spec.rb
+++ b/spec/finders/merge_requests_finder_spec.rb
@@ -16,12 +16,18 @@ describe MergeRequestsFinder do
     p
   end
   let(:project4) { create(:project, :public, group: subgroup) }
+  let(:project5) { create(:project, :public, group: subgroup) }
+  let(:project6) { create(:project, :public, group: subgroup) }
 
   let!(:merge_request1) { create(:merge_request, :simple, author: user, source_project: project2, target_project: project1) }
   let!(:merge_request2) { create(:merge_request, :conflict, author: user, source_project: project2, target_project: project1, state: 'closed') }
-  let!(:merge_request3) { create(:merge_request, :simple, author: user, source_project: project2, target_project: project2, state: 'locked') }
-  let!(:merge_request4) { create(:merge_request, :simple, author: user, source_project: project3, target_project: project3) }
-  let!(:merge_request5) { create(:merge_request, :simple, author: user, source_project: project4, target_project: project4) }
+  let!(:merge_request3) { create(:merge_request, :simple, author: user, source_project: project2, target_project: project2, state: 'locked', title: 'thing WIP thing') }
+  let!(:merge_request4) { create(:merge_request, :simple, author: user, source_project: project3, target_project: project3, title: 'WIP thing') }
+  let!(:merge_request5) { create(:merge_request, :simple, author: user, source_project: project4, target_project: project4, title: '[WIP]') }
+  let!(:merge_request6) { create(:merge_request, :simple, author: user, source_project: project5, target_project: project5, title: 'WIP: thing') }
+  let!(:merge_request7) { create(:merge_request, :simple, author: user, source_project: project6, target_project: project6, title: 'wip thing') }
+  let!(:merge_request8) { create(:merge_request, :simple, author: user, source_project: project1, target_project: project1, title: '[wip] thing') }
+  let!(:merge_request9) { create(:merge_request, :simple, author: user, source_project: project1, target_project: project2, title: 'wip: thing') }
 
   before do
     project1.add_maintainer(user)
@@ -29,19 +35,21 @@ describe MergeRequestsFinder do
     project3.add_developer(user)
     project2.add_developer(user2)
     project4.add_developer(user)
+    project5.add_developer(user)
+    project6.add_developer(user)
   end
 
   describe "#execute" do
     it 'filters by scope' do
       params = { scope: 'authored', state: 'opened' }
       merge_requests = described_class.new(user, params).execute
-      expect(merge_requests.size).to eq(3)
+      expect(merge_requests.size).to eq(7)
     end
 
     it 'filters by project' do
       params = { project_id: project1.id, scope: 'authored', state: 'opened' }
       merge_requests = described_class.new(user, params).execute
-      expect(merge_requests.size).to eq(1)
+      expect(merge_requests.size).to eq(2)
     end
 
     it 'filters by group' do
@@ -49,7 +57,7 @@ describe MergeRequestsFinder do
 
       merge_requests = described_class.new(user, params).execute
 
-      expect(merge_requests.size).to eq(2)
+      expect(merge_requests.size).to eq(3)
     end
 
     it 'filters by group including subgroups', :nested_groups do
@@ -57,13 +65,13 @@ describe MergeRequestsFinder do
 
       merge_requests = described_class.new(user, params).execute
 
-      expect(merge_requests.size).to eq(3)
+      expect(merge_requests.size).to eq(6)
     end
 
     it 'filters by non_archived' do
       params = { non_archived: true }
       merge_requests = described_class.new(user, params).execute
-      expect(merge_requests.size).to eq(4)
+      expect(merge_requests.size).to eq(8)
     end
 
     it 'filters by iid' do
@@ -98,6 +106,36 @@ describe MergeRequestsFinder do
       expect(merge_requests).to contain_exactly(merge_request3)
     end
 
+    it 'filters by wip' do
+      params = { wip: 'yes' }
+
+      merge_requests = described_class.new(user, params).execute
+
+      expect(merge_requests).to contain_exactly(merge_request4, merge_request5, merge_request6, merge_request7, merge_request8, merge_request9)
+    end
+
+    it 'filters by not wip' do
+      params = { wip: 'no' }
+
+      merge_requests = described_class.new(user, params).execute
+
+      expect(merge_requests).to contain_exactly(merge_request1, merge_request2, merge_request3)
+    end
+
+    it 'returns all items if no valid wip param exists' do
+      params = { wip: '' }
+
+      merge_requests = described_class.new(user, params).execute
+
+      expect(merge_requests).to contain_exactly(merge_request1, merge_request2, merge_request3, merge_request4, merge_request5, merge_request6, merge_request7, merge_request8, merge_request9)
+    end
+
+    it 'adds wip to scalar params' do
+      scalar_params = described_class.scalar_params
+
+      expect(scalar_params).to include(:wip, :assignee_id)
+    end
+
     context 'filtering by group milestone' do
       let!(:group) { create(:group, :public) }
       let(:group_milestone) { create(:milestone, group: group) }
@@ -207,7 +245,7 @@ describe MergeRequestsFinder do
     it 'returns the number of rows for the default state' do
       finder = described_class.new(user)
 
-      expect(finder.row_count).to eq(3)
+      expect(finder.row_count).to eq(7)
     end
 
     it 'returns the number of rows for a given state' do
diff --git a/spec/javascripts/filtered_search/dropdown_utils_spec.js b/spec/javascripts/filtered_search/dropdown_utils_spec.js
index 8792e99d461..68bbbf838da 100644
--- a/spec/javascripts/filtered_search/dropdown_utils_spec.js
+++ b/spec/javascripts/filtered_search/dropdown_utils_spec.js
@@ -288,13 +288,13 @@ describe('Dropdown Utils', () => {
 
   describe('setDataValueIfSelected', () => {
     beforeEach(() => {
-      spyOn(FilteredSearchDropdownManager, 'addWordToInput')
-        .and.callFake(() => {});
+      spyOn(FilteredSearchDropdownManager, 'addWordToInput').and.callFake(() => {});
     });
 
     it('calls addWordToInput when dataValue exists', () => {
       const selected = {
         getAttribute: () => 'value',
+        hasAttribute: () => false,
       };
 
       DropdownUtils.setDataValueIfSelected(null, selected);
@@ -304,6 +304,7 @@ describe('Dropdown Utils', () => {
     it('returns true when dataValue exists', () => {
       const selected = {
         getAttribute: () => 'value',
+        hasAttribute: () => false,
       };
 
       const result = DropdownUtils.setDataValueIfSelected(null, selected);
diff --git a/spec/javascripts/filtered_search/filtered_search_visual_tokens_spec.js b/spec/javascripts/filtered_search/filtered_search_visual_tokens_spec.js
index 756a654765b..53a6d1d62b0 100644
--- a/spec/javascripts/filtered_search/filtered_search_visual_tokens_spec.js
+++ b/spec/javascripts/filtered_search/filtered_search_visual_tokens_spec.js
@@ -240,13 +240,17 @@ describe('Filtered Search Visual Tokens', () => {
     beforeEach(() => {
       setFixtures(`
         <div class="test-area">
-        ${subject.createVisualTokenElementHTML()}
+        ${subject.createVisualTokenElementHTML('custom-token')}
         </div>
       `);
 
       tokenElement = document.querySelector('.test-area').firstElementChild;
     });
 
+    it('should add class name to token element', () => {
+      expect(document.querySelector('.test-area .custom-token')).toBeDefined();
+    });
+
     it('contains name div', () => {
       expect(tokenElement.querySelector('.name')).toEqual(jasmine.anything());
     });
@@ -280,7 +284,7 @@ describe('Filtered Search Visual Tokens', () => {
 
   describe('addVisualTokenElement', () => {
     it('renders search visual tokens', () => {
-      subject.addVisualTokenElement('search term', null, true);
+      subject.addVisualTokenElement('search term', null, { isSearchTerm: true });
       const token = tokensContainer.querySelector('.js-visual-token');
 
       expect(token.classList.contains('filtered-search-term')).toEqual(true);
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 48f4e53b93e..666d7e69f89 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -746,7 +746,7 @@ describe MergeRequest do
   end
 
   describe "#wipless_title" do
-    ['WIP ', 'WIP:', 'WIP: ', '[WIP]', '[WIP] ', ' [WIP] WIP [WIP] WIP: WIP '].each do |wip_prefix|
+    ['WIP ', 'WIP:', 'WIP: ', '[WIP]', '[WIP] ', '[WIP] WIP [WIP] WIP: WIP '].each do |wip_prefix|
       it "removes the '#{wip_prefix}' prefix" do
         wipless_title = subject.title
         subject.title = "#{wip_prefix}#{subject.title}"
diff --git a/spec/requests/api/merge_requests_spec.rb b/spec/requests/api/merge_requests_spec.rb
index e987eee6e91..07d19e3ad29 100644
--- a/spec/requests/api/merge_requests_spec.rb
+++ b/spec/requests/api/merge_requests_spec.rb
@@ -81,6 +81,35 @@ describe API::MergeRequests do
       let(:user2) { create(:user) }
 
       it 'returns an array of all merge requests except unauthorized ones' do
+        get api('/merge_requests', user), scope: :all
+
+        expect(response).to have_gitlab_http_status(200)
+        expect(response).to include_pagination_headers
+        expect(json_response).to be_an Array
+        expect(json_response.map { |mr| mr['id'] })
+          .to contain_exactly(merge_request.id, merge_request_closed.id, merge_request_merged.id, merge_request_locked.id, merge_request2.id)
+      end
+
+      it "returns an array of no merge_requests when wip=yes" do
+        get api("/merge_requests", user), wip: 'yes'
+
+        expect(response).to have_gitlab_http_status(200)
+        expect(response).to include_pagination_headers
+        expect(json_response).to be_an Array
+        expect(json_response.length).to eq(0)
+      end
+
+      it "returns an array of no merge_requests when wip=no" do
+        get api("/merge_requests", user), wip: 'no'
+
+        expect(response).to have_gitlab_http_status(200)
+        expect(response).to include_pagination_headers
+        expect(json_response).to be_an Array
+        expect(json_response.map { |mr| mr['id'] })
+            .to contain_exactly(merge_request.id, merge_request_closed.id, merge_request_merged.id, merge_request_locked.id, merge_request2.id)
+      end
+
+      it 'does not return unauthorized merge requests' do
         private_project = create(:project, :private)
         merge_request3 = create(:merge_request, :simple, source_project: private_project, target_project: private_project, source_branch: 'other-branch')
 
@@ -244,6 +273,15 @@ describe API::MergeRequests do
       expect(response).to have_gitlab_http_status(404)
     end
 
+    it "returns an array of no merge_requests when wip=yes" do
+      get api("/projects/#{project.id}/merge_requests", user), wip: 'yes'
+
+      expect(response).to have_gitlab_http_status(200)
+      expect(response).to include_pagination_headers
+      expect(json_response).to be_an Array
+      expect(json_response.length).to eq(0)
+    end
+
     it 'returns merge_request by "iids" array' do
       get api(endpoint_path, user), iids: [merge_request.iid, merge_request_closed.iid]