Roughly implement milestone columns on workboards

Summary:
Ref T10010. These aren't perfect but I think (?) they aren't horribly broken.

  - When a project is a parent project, destroy (as far as the user can tell) any custom columns.
  - When a project has milestones, automatically generate columns on the project's workboard (if it has a workboard).
  - When you move tasks between milestones, add the proper milestone tag.
  - When you move tasks out of milestones back into the backlog, add the proper parent project tag.
  - (Plenty of UI / design stuff to adjust.)

Test Plan:
  - Dragged stuff between milestone columns.
  - Used a normal workboard.
  - Wasn't able to find any egregiously bad cases that did anything terrible.

{F1088224}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10010

Differential Revision: https://secure.phabricator.com/D15171

resources/celerity/map.php

@@ -413,7 +413,7 @@ return array(
     'rsrc/js/application/phortune/phortune-credit-card-form.js' => '2290aeef',
     'rsrc/js/application/policy/behavior-policy-control.js' => 'ae45872f',
     'rsrc/js/application/policy/behavior-policy-rule-editor.js' => '5e9f347c',
-    'rsrc/js/application/projects/behavior-project-boards.js' => 'c05fb42a',
+    'rsrc/js/application/projects/behavior-project-boards.js' => '48470f95',
     'rsrc/js/application/projects/behavior-project-create.js' => '065227cc',
     'rsrc/js/application/projects/behavior-reorder-columns.js' => 'e1d25dfb',
     'rsrc/js/application/releeph/releeph-preview-branch.js' => 'b2b4fbaf',
@@ -653,7 +653,7 @@ return array(
     'javelin-behavior-phui-profile-menu' => '12884df9',
     'javelin-behavior-policy-control' => 'ae45872f',
     'javelin-behavior-policy-rule-editor' => '5e9f347c',
-    'javelin-behavior-project-boards' => 'c05fb42a',
+    'javelin-behavior-project-boards' => '48470f95',
     'javelin-behavior-project-create' => '065227cc',
     'javelin-behavior-quicksand-blacklist' => '7927a7d3',
     'javelin-behavior-recurring-edit' => '5f1c4d5f',
@@ -1151,6 +1151,15 @@ return array(
       'javelin-dom',
       'javelin-workflow',
     ),
+    '48470f95' => array(
+      'javelin-behavior',
+      'javelin-dom',
+      'javelin-util',
+      'javelin-vector',
+      'javelin-stratcom',
+      'javelin-workflow',
+      'phabricator-draggable-list',
+    ),
     '49b73b36' => array(
       'javelin-behavior',
       'javelin-dom',
@@ -1779,15 +1788,6 @@ return array(
       'javelin-install',
       'javelin-dom',
     ),
-    'c05fb42a' => array(
-      'javelin-behavior',
-      'javelin-dom',
-      'javelin-util',
-      'javelin-vector',
-      'javelin-stratcom',
-      'javelin-workflow',
-      'phabricator-draggable-list',
-    ),
     'c1700f6f' => array(
       'javelin-install',
       'javelin-util',

resources/sql/autopatches/20160202.board.1.proxy.sql

@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_project.project_column
+  ADD proxyPHID VARBINARY(64);

src/__phutil_library_map__.php

@@ -1889,6 +1889,7 @@ phutil_register_library_map(array(
     'PhabricatorChatLogQuery' => 'applications/chatlog/query/PhabricatorChatLogQuery.php',
     'PhabricatorChunkedFileStorageEngine' => 'applications/files/engine/PhabricatorChunkedFileStorageEngine.php',
     'PhabricatorClusterConfigOptions' => 'applications/config/option/PhabricatorClusterConfigOptions.php',
+    'PhabricatorColumnProxyInterface' => 'applications/project/interface/PhabricatorColumnProxyInterface.php',
     'PhabricatorCommentEditEngineExtension' => 'applications/transactions/engineextension/PhabricatorCommentEditEngineExtension.php',
     'PhabricatorCommentEditField' => 'applications/transactions/editfield/PhabricatorCommentEditField.php',
     'PhabricatorCommentEditType' => 'applications/transactions/edittype/PhabricatorCommentEditType.php',
@@ -7262,6 +7263,7 @@ phutil_register_library_map(array(
       'PhabricatorDestructibleInterface',
       'PhabricatorFulltextInterface',
       'PhabricatorConduitResultInterface',
+      'PhabricatorColumnProxyInterface',
     ),
     'PhabricatorProjectAddHeraldAction' => 'PhabricatorProjectHeraldAction',
     'PhabricatorProjectApplication' => 'PhabricatorApplication',

src/applications/maniphest/editor/ManiphestEditEngine.php

@@ -280,10 +280,23 @@ final class ManiphestEditEngine
       return new Aphront404Response();
     }
 
-    // If the workboard's project has been removed from the card's project
-    // list, we are going to remove it from the board completely.
+    // If the workboard's project and all descendant projects have been removed
+    // from the card's project list, we are going to remove it from the board
+    // completely.
+
+    // TODO: If the user did something sneaky and changed a subproject, we'll
+    // currently leave the card where it was but should really move it to the
+    // proper new column.
+
+    $descendant_projects = id(new PhabricatorProjectQuery())
+      ->setViewer($viewer)
+      ->withAncestorProjectPHIDs(array($column->getProjectPHID()))
+      ->execute();
+    $board_phids = mpull($descendant_projects, 'getPHID', 'getPHID');
+    $board_phids[$column->getProjectPHID()] = $column->getProjectPHID();
+
     $project_map = array_fuse($task->getProjectPHIDs());
-    $remove_card = empty($project_map[$column->getProjectPHID()]);
+    $remove_card = !array_intersect_key($board_phids, $project_map);
 
     $positions = id(new PhabricatorProjectColumnPositionQuery())
       ->setViewer($viewer)

src/applications/maniphest/editor/ManiphestTransactionEditor.php

@@ -222,12 +222,22 @@ final class ManiphestTransactionEditor
         // can't see.
         $omnipotent_viewer = PhabricatorUser::getOmnipotentUser();
 
+        $select_phids = array($board_phid);
+
+        $descendants = id(new PhabricatorProjectQuery())
+          ->setViewer($omnipotent_viewer)
+          ->withAncestorProjectPHIDs($select_phids)
+          ->execute();
+        foreach ($descendants as $descendant) {
+          $select_phids[] = $descendant->getPHID();
+        }
+
         $board_tasks = id(new ManiphestTaskQuery())
           ->setViewer($omnipotent_viewer)
           ->withEdgeLogicPHIDs(
             PhabricatorProjectObjectHasProjectEdgeType::EDGECONST,
-            PhabricatorQueryConstraint::OPERATOR_AND,
-            array($board_phid))
+            PhabricatorQueryConstraint::OPERATOR_ANCESTOR,
+            array($select_phids))
           ->execute();
 
         $object_phids = mpull($board_tasks, 'getPHID');

src/applications/project/__tests__/PhabricatorProjectCoreTestCase.php

@@ -972,7 +972,45 @@ final class PhabricatorProjectCoreTestCase extends PhabricatorTestCase {
       $task1->getPHID(),
     );
     $this->assertTasksInColumn($expect, $user, $board, $column);
+  }
 
+  public function testMilestoneMoves() {
+    $user = $this->createUser();
+    $user->save();
+
+    $board = $this->createProject($user);
+
+    $backlog = $this->addColumn($user, $board, 0);
+
+    // Create a task into the backlog.
+    $task = $this->newTask($user, array($board));
+    $expect = array(
+      $backlog->getPHID(),
+    );
+    $this->assertColumns($expect, $user, $board, $task);
+
+    $milestone = $this->createProject($user, $board, true);
+
+    $this->addProjectTags($user, $task, array($milestone->getPHID()));
+
+    // We just want the side effect of looking at the board: creation of the
+    // milestone column.
+    $this->loadColumns($user, $board, $task);
+
+    $column = id(new PhabricatorProjectColumnQuery())
+      ->setViewer($user)
+      ->withProjectPHIDs(array($board->getPHID()))
+      ->withProxyPHIDs(array($milestone->getPHID()))
+      ->executeOne();
+
+    $this->assertTrue((bool)$column);
+
+    // Moving the task to the milestone should have moved it to the milestone
+    // column.
+    $expect = array(
+      $column->getPHID(),
+    );
+    $this->assertColumns($expect, $user, $board, $task);
   }
 
   private function moveToColumn(
@@ -1014,7 +1052,14 @@ final class PhabricatorProjectCoreTestCase extends PhabricatorTestCase {
     PhabricatorUser $viewer,
     PhabricatorProject $board,
     ManiphestTask $task) {
+    $column_phids = $this->loadColumns($viewer, $board, $task);
+    $this->assertEqual($expect, $column_phids);
+  }
 
+  private function loadColumns(
+    PhabricatorUser $viewer,
+    PhabricatorProject $board,
+    ManiphestTask $task) {
     $engine = id(new PhabricatorBoardLayoutEngine())
       ->setViewer($viewer)
       ->setBoardPHIDs(array($board->getPHID()))
@@ -1028,7 +1073,7 @@ final class PhabricatorProjectCoreTestCase extends PhabricatorTestCase {
     $column_phids = mpull($columns, 'getPHID');
     $column_phids = array_values($column_phids);
 
-    $this->assertEqual($expect, $column_phids);
+    return $column_phids;
   }
 
   private function assertTasksInColumn(
@@ -1236,6 +1281,16 @@ final class PhabricatorProjectCoreTestCase extends PhabricatorTestCase {
 
     $this->applyTransactions($project, $user, $xactions);
 
+    // Force these values immediately; they are normally updated by the
+    // index engine.
+    if ($parent) {
+      if ($is_milestone) {
+        $parent->setHasMilestones(1)->save();
+      } else {
+        $parent->setHasSubprojects(1)->save();
+      }
+    }
+
     return $project;
   }
 

src/applications/project/controller/PhabricatorProjectBoardViewController.php

@@ -95,17 +95,27 @@ final class PhabricatorProjectBoardViewController
 
     $task_query = $search_engine->buildQueryFromSavedQuery($saved);
 
+    $select_phids = array($project->getPHID());
+    if ($project->getHasSubprojects() || $project->getHasMilestones()) {
+      $descendants = id(new PhabricatorProjectQuery())
+        ->setViewer($viewer)
+        ->withAncestorProjectPHIDs($select_phids)
+        ->execute();
+      foreach ($descendants as $descendant) {
+        $select_phids[] = $descendant->getPHID();
+      }
+    }
+
     $tasks = $task_query
       ->withEdgeLogicPHIDs(
         PhabricatorProjectObjectHasProjectEdgeType::EDGECONST,
-        PhabricatorQueryConstraint::OPERATOR_AND,
-        array($project->getPHID()))
+        PhabricatorQueryConstraint::OPERATOR_ANCESTOR,
+        array($select_phids))
       ->setOrder(ManiphestTaskQuery::ORDER_PRIORITY)
       ->setViewer($viewer)
       ->execute();
     $tasks = mpull($tasks, null, 'getPHID');
 
-
     $board_phid = $project->getPHID();
 
     $layout_engine = id(new PhabricatorBoardLayoutEngine())
@@ -225,6 +235,13 @@ final class PhabricatorProjectBoardViewController
         }
       }
 
+      $proxy = $column->getProxy();
+      if ($proxy && !$proxy->isMilestone()) {
+        // TODO: For now, don't show subproject columns because we can't
+        // handle tasks with multiple positions yet.
+        continue;
+      }
+
       $task_phids = $layout_engine->getColumnObjectPHIDs(
         $board_phid,
         $column->getPHID());
@@ -247,6 +264,11 @@ final class PhabricatorProjectBoardViewController
         $panel->setHeaderIcon($header_icon);
       }
 
+      $display_class = $column->getDisplayClass();
+      if ($display_class) {
+        $panel->addClass($display_class);
+      }
+
       if ($column->isHidden()) {
         $panel->addClass('project-panel-hidden');
       }
@@ -582,6 +604,12 @@ final class PhabricatorProjectBoardViewController
 
     $column_items = array();
 
+    if ($column->getProxyPHID()) {
+      $default_phid = $column->getProxyPHID();
+    } else {
+      $default_phid = $column->getProjectPHID();
+    }
+
     $column_items[] = id(new PhabricatorActionView())
       ->setIcon('fa-plus')
       ->setName(pht('Create Task...'))
@@ -590,6 +618,7 @@ final class PhabricatorProjectBoardViewController
       ->setMetadata(
         array(
           'columnPHID' => $column->getPHID(),
+          'projectPHID' => $default_phid,
         ));
 
     $batch_edit_uri = $request->getRequestURI();
@@ -738,6 +767,10 @@ final class PhabricatorProjectBoardViewController
       }
     }
 
+    // TODO: Tailor this UI if the project is already a parent project. We
+    // should not offer options for creating a parent project workboard, since
+    // they can't have their own columns.
+
     $new_selector = id(new AphrontFormRadioButtonControl())
       ->setLabel(pht('Columns'))
       ->setName('initialize-type')

src/applications/project/controller/PhabricatorProjectMoveController.php

@@ -139,7 +139,33 @@ final class PhabricatorProjectMoveController
           ->setTransactionType(ManiphestTransaction::TYPE_SUBPRIORITY)
           ->setNewValue($sub);
       }
-   }
+    }
+
+    $proxy = $column->getProxy();
+    if ($proxy) {
+      // We're moving the task into a subproject or milestone column, so add
+      // the subproject or milestone.
+      $add_projects = array($proxy->getPHID());
+    } else if ($project->getHasSubprojects() || $project->getHasMilestones()) {
+      // We're moving the task into the "Backlog" column on the parent project,
+      // so add the parent explicitly. This gets rid of any subproject or
+      // milestone tags.
+      $add_projects = array($project->getPHID());
+    } else {
+      $add_projects = array();
+    }
+
+    if ($add_projects) {
+      $project_type = PhabricatorProjectObjectHasProjectEdgeType::EDGECONST;
+
+      $xactions[] = id(new ManiphestTransaction())
+        ->setTransactionType(PhabricatorTransactions::TYPE_EDGE)
+        ->setMetadataValue('edge:type', $project_type)
+        ->setNewValue(
+          array(
+            '+' => array_fuse($add_projects),
+          ));
+    }
 
     $editor = id(new ManiphestTransactionEditor())
       ->setActor($viewer)
@@ -157,6 +183,18 @@ final class PhabricatorProjectMoveController
         ->executeOne();
     }
 
+    // Reload the object so it reflects edits which have been applied.
+    $object = id(new ManiphestTaskQuery())
+      ->setViewer($viewer)
+      ->withPHIDs(array($object_phid))
+      ->needProjectPHIDs(true)
+      ->requireCapabilities(
+        array(
+          PhabricatorPolicyCapability::CAN_VIEW,
+          PhabricatorPolicyCapability::CAN_EDIT,
+        ))
+      ->executeOne();
+
     $card = id(new ProjectBoardTaskCard())
       ->setViewer($viewer)
       ->setTask($object)
@@ -169,6 +207,6 @@ final class PhabricatorProjectMoveController
 
     return id(new AphrontAjaxResponse())->setContent(
       array('task' => $card));
- }
+  }
 
 }

src/applications/project/controller/PhabricatorProjectSubprojectWarningController.php

@@ -35,7 +35,7 @@ final class PhabricatorProjectSubprojectWarningController
 
     $conversion_help = pht(
       "Creating a project's first subproject **moves all ".
-      "members** and **destroys all workboard columns**.".
+      "members** to become members of the subproject instead".
       "\n\n".
       "See [[ %s | Projects User Guide ]] in the documentation for details. ".
       "This process can not be undone.",

src/applications/project/engine/PhabricatorBoardLayoutEngine.php

@@ -320,8 +320,63 @@ final class PhabricatorBoardLayoutEngine extends Phobject {
     $columns = msort($columns, 'getSequence');
     $columns = mpull($columns, null, 'getPHID');
 
-    $this->columnMap = $columns;
+    $need_children = array();
+    foreach ($boards as $phid => $board) {
+      if ($board->getHasMilestones() || $board->getHasSubprojects()) {
+        $need_children[] = $phid;
+      }
+    }
+
+    if ($need_children) {
+      $children = id(new PhabricatorProjectQuery())
+        ->setViewer($viewer)
+        ->withParentProjectPHIDs($need_children)
+        ->execute();
+      $children = mpull($children, null, 'getPHID');
+      $children = mgroup($children, 'getParentProjectPHID');
+    } else {
+      $children = array();
+    }
+
     $columns = mgroup($columns, 'getProjectPHID');
+    foreach ($boards as $board_phid => $board) {
+      $board_columns = idx($columns, $board_phid, array());
+
+      // If the project has milestones, create any missing columns.
+      if ($board->getHasMilestones() || $board->getHasSubprojects()) {
+        $child_projects = idx($children, $board_phid, array());
+
+        $next_sequence = last($board_columns)->getSequence() + 1;
+        $proxy_columns = mpull($board_columns, null, 'getProxyPHID');
+        foreach ($child_projects as $child_phid => $child) {
+          if (isset($proxy_columns[$child_phid])) {
+            continue;
+          }
+
+          $new_column = PhabricatorProjectColumn::initializeNewColumn($viewer)
+            ->attachProject($board)
+            ->attachProxy($child)
+            ->setSequence($next_sequence++)
+            ->setProjectPHID($board_phid)
+            ->setProxyPHID($child_phid);
+
+          $unguarded = AphrontWriteGuard::beginScopedUnguardedWrites();
+            $new_column->save();
+          unset($unguarded);
+
+          $board_columns[$new_column->getPHID()] = $new_column;
+        }
+      }
+
+      $columns[$board_phid] = $board_columns;
+    }
+
+    foreach ($columns as $board_phid => $board_columns) {
+      foreach ($board_columns as $board_column) {
+        $column_phid = $board_column->getPHID();
+        $this->columnMap[$column_phid] = $board_column;
+      }
+    }
 
     return $columns;
   }
@@ -350,6 +405,8 @@ final class PhabricatorBoardLayoutEngine extends Phobject {
     array $columns,
     array $positions) {
 
+    $viewer = $this->getViewer();
+
     $board_phid = $board->getPHID();
     $position_groups = mgroup($positions, 'getObjectPHID');
 
@@ -363,32 +420,143 @@ final class PhabricatorBoardLayoutEngine extends Phobject {
       }
     }
 
+    // Find all the columns which are proxies for other objects.
+    $proxy_map = array();
+    foreach ($columns as $column) {
+      $proxy_phid = $column->getProxyPHID();
+      if ($proxy_phid) {
+        $proxy_map[$proxy_phid] = $column->getPHID();
+      }
+    }
+
     $object_phids = $this->getObjectPHIDs();
+
+    // If we have proxies, we need to force cards into the correct proxy
+    // columns.
+    if ($proxy_map) {
+      $edge_query = id(new PhabricatorEdgeQuery())
+        ->withSourcePHIDs($object_phids)
+        ->withEdgeTypes(
+          array(
+            PhabricatorProjectObjectHasProjectEdgeType::EDGECONST,
+          ));
+      $edge_query->execute();
+
+      $project_phids = $edge_query->getDestinationPHIDs();
+      $project_phids = array_fuse($project_phids);
+    } else {
+      $project_phids = array();
+    }
+
+    if ($project_phids) {
+      $projects = id(new PhabricatorProjectQuery())
+        ->setViewer($viewer)
+        ->withPHIDs($project_phids)
+        ->execute();
+      $projects = mpull($projects, null, 'getPHID');
+    } else {
+      $projects = array();
+    }
+
+    // Build a map from every project that any task is tagged with to the
+    // ancestor project which has a column on this board, if one exists.
+    $ancestor_map = array();
+    foreach ($projects as $phid => $project) {
+      if (isset($proxy_map[$phid])) {
+        $ancestor_map[$phid] = $proxy_map[$phid];
+      } else {
+        $seen = array($phid);
+        foreach ($project->getAncestorProjects() as $ancestor) {
+          $ancestor_phid = $ancestor->getPHID();
+          $seen[] = $ancestor_phid;
+          if (isset($proxy_map[$ancestor_phid])) {
+            foreach ($seen as $project_phid) {
+              $ancestor_map[$project_phid] = $proxy_map[$ancestor_phid];
+            }
+          }
+        }
+      }
+    }
+
     foreach ($object_phids as $object_phid) {
       $positions = idx($position_groups, $object_phid, array());
 
-      // Remove any positions in columns which no longer exist.
-      foreach ($positions as $key => $position) {
-        $column_phid = $position->getColumnPHID();
-        if (empty($columns[$column_phid])) {
-          $this->remQueue[] = $position;
-          unset($positions[$key]);
+      // First, check for objects that have corresponding proxy columns. We're
+      // going to overwrite normal column positions if a tag belongs to a proxy
+      // column, since you can't be in normal columns if you're in proxy
+      // columns.
+      $proxy_hits = array();
+      if ($proxy_map) {
+        $object_project_phids = $edge_query->getDestinationPHIDs(
+          array(
+            $object_phid,
+          ));
+
+        foreach ($object_project_phids as $project_phid) {
+          if (isset($ancestor_map[$project_phid])) {
+            $proxy_hits[] = $ancestor_map[$project_phid];
+          }
         }
       }
 
-      // If the object has no position, put it on the default column.
-      if (!$positions) {
-        $new_position = id(new PhabricatorProjectColumnPosition())
-          ->setBoardPHID($board_phid)
-          ->setColumnPHID($default_phid)
-          ->setObjectPHID($object_phid)
-          ->setSequence(0);
+      if ($proxy_hits) {
+        // TODO: For now, only one column hit is permissible.
+        $proxy_hits = array_slice($proxy_hits, 0, 1);
 
-        $this->addQueue[] = $new_position;
+        $proxy_hits = array_fuse($proxy_hits);
 
-        $positions = array(
-          $new_position,
-        );
+        // Check the object positions: we hope to find a position in each
+        // column the object should be part of. We're going to drop any
+        // invalid positions and create new positions where positions are
+        // missing.
+        foreach ($positions as $key => $position) {
+          $column_phid = $position->getColumnPHID();
+          if (isset($proxy_hits[$column_phid])) {
+            // Valid column, mark the position as found.
+            unset($proxy_hits[$column_phid]);
+          } else {
+            // Invalid column, ignore the position.
+            unset($positions[$key]);
+          }
+        }
+
+        // Create new positions for anything we haven't found.
+        foreach ($proxy_hits as $proxy_hit) {
+          $new_position = id(new PhabricatorProjectColumnPosition())
+            ->setBoardPHID($board_phid)
+            ->setColumnPHID($proxy_hit)
+            ->setObjectPHID($object_phid)
+            ->setSequence(0);
+
+          $this->addQueue[] = $new_position;
+
+          $positions[] = $new_position;
+        }
+      } else {
+        // Ignore any positions in columns which no longer exist. We don't
+        // actively destory them because the rest of the code ignores them and
+        // there's no real need to destroy the data.
+        foreach ($positions as $key => $position) {
+          $column_phid = $position->getColumnPHID();
+          if (empty($columns[$column_phid])) {
+            unset($positions[$key]);
+          }
+        }
+
+        // If the object has no position, put it on the default column.
+        if (!$positions) {
+          $new_position = id(new PhabricatorProjectColumnPosition())
+            ->setBoardPHID($board_phid)
+            ->setColumnPHID($default_phid)
+            ->setObjectPHID($object_phid)
+            ->setSequence(0);
+
+          $this->addQueue[] = $new_position;
+
+          $positions = array(
+            $new_position,
+          );
+        }
       }
 
       foreach ($positions as $position) {

src/applications/project/interface/PhabricatorColumnProxyInterface.php

@@ -0,0 +1,7 @@
+<?php
+
+interface PhabricatorColumnProxyInterface {
+
+  public function getProxyColumnName();
+
+}

src/applications/project/query/PhabricatorProjectColumnQuery.php

@@ -6,6 +6,7 @@ final class PhabricatorProjectColumnQuery
   private $ids;
   private $phids;
   private $projectPHIDs;
+  private $proxyPHIDs;
   private $statuses;
 
   public function withIDs(array $ids) {
@@ -23,6 +24,11 @@ final class PhabricatorProjectColumnQuery
     return $this;
   }
 
+  public function withProxyPHIDs(array $proxy_phids) {
+    $this->proxyPHIDs = $proxy_phids;
+    return $this;
+  }
+
   public function withStatuses(array $status) {
     $this->statuses = $status;
     return $this;
@@ -60,6 +66,55 @@ final class PhabricatorProjectColumnQuery
       $column->attachProject($project);
     }
 
+    $proxy_phids = array_filter(mpull($page, 'getProjectPHID'));
+
+    return $page;
+  }
+
+  protected function didFilterPage(array $page) {
+    $proxy_phids = array();
+    foreach ($page as $column) {
+      $proxy_phid = $column->getProxyPHID();
+      if ($proxy_phid !== null) {
+        $proxy_phids[$proxy_phid] = $proxy_phid;
+      }
+    }
+
+    if ($proxy_phids) {
+      $proxies = id(new PhabricatorObjectQuery())
+        ->setParentQuery($this)
+        ->setViewer($this->getViewer())
+        ->withPHIDs($proxy_phids)
+        ->execute();
+      $proxies = mpull($proxies, null, 'getPHID');
+    } else {
+      $proxies = array();
+    }
+
+    foreach ($page as $key => $column) {
+      $proxy_phid = $column->getProxyPHID();
+
+      if ($proxy_phid !== null) {
+        $proxy = idx($proxies, $proxy_phid);
+
+        // Only attach valid proxies, so we don't end up getting surprsied if
+        // an install somehow gets junk into their database.
+        if (!($proxy instanceof PhabricatorColumnProxyInterface)) {
+          $proxy = null;
+        }
+
+        if (!$proxy) {
+          $this->didRejectResult($column);
+          unset($page[$key]);
+          continue;
+        }
+      } else {
+        $proxy = null;
+      }
+
+      $column->attachProxy($proxy);
+    }
+
     return $page;
   }
 
@@ -87,6 +142,13 @@ final class PhabricatorProjectColumnQuery
         $this->projectPHIDs);
     }
 
+    if ($this->proxyPHIDs !== null) {
+      $where[] = qsprintf(
+        $conn,
+        'proxyPHID IN (%Ls)',
+        $this->proxyPHIDs);
+    }
+
     if ($this->statuses !== null) {
       $where[] = qsprintf(
         $conn,

src/applications/project/storage/PhabricatorProject.php

@@ -9,7 +9,8 @@ final class PhabricatorProject extends PhabricatorProjectDAO
     PhabricatorCustomFieldInterface,
     PhabricatorDestructibleInterface,
     PhabricatorFulltextInterface,
-    PhabricatorConduitResultInterface {
+    PhabricatorConduitResultInterface,
+    PhabricatorColumnProxyInterface {
 
   protected $name;
   protected $status = PhabricatorProjectStatus::STATUS_ACTIVE;
@@ -663,4 +664,25 @@ final class PhabricatorProject extends PhabricatorProjectDAO
     );
   }
 
+
+/* -(  PhabricatorColumnProxyInterface  )------------------------------------ */
+
+
+  public function getProxyColumnName() {
+    return $this->getName();
+  }
+
+  public function getProxyColumnIcon() {
+    return $this->getDisplayIconIcon();
+  }
+
+  public function getProxyColumnClass() {
+    if ($this->isMilestone()) {
+      return 'phui-workboard-column-milestone';
+    }
+
+    return null;
+  }
+
+
 }

src/applications/project/storage/PhabricatorProjectColumn.php

@@ -17,10 +17,12 @@ final class PhabricatorProjectColumn
   protected $name;
   protected $status;
   protected $projectPHID;
+  protected $proxyPHID;
   protected $sequence;
   protected $properties = array();
 
   private $project = self::ATTACHABLE;
+  private $proxy = self::ATTACHABLE;
 
   public static function initializeNewColumn(PhabricatorUser $user) {
     return id(new PhabricatorProjectColumn())
@@ -38,6 +40,7 @@ final class PhabricatorProjectColumn
         'name' => 'text255',
         'status' => 'uint32',
         'sequence' => 'uint32',
+        'proxyPHID' => 'phid?',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_status' => array(
@@ -46,6 +49,10 @@ final class PhabricatorProjectColumn
         'key_sequence' => array(
           'columns' => array('projectPHID', 'sequence'),
         ),
+        'key_proxy' => array(
+          'columns' => array('projectPHID', 'proxyPHID'),
+          'unique' => true,
+        ),
       ),
     ) + parent::getConfiguration();
   }
@@ -64,6 +71,15 @@ final class PhabricatorProjectColumn
     return $this->assertAttached($this->project);
   }
 
+  public function attachProxy($proxy) {
+    $this->proxy = $proxy;
+    return $this;
+  }
+
+  public function getProxy() {
+    return $this->assertAttached($this->proxy);
+  }
+
   public function isDefaultColumn() {
     return (bool)$this->getProperty('isDefault');
   }
@@ -73,6 +89,11 @@ final class PhabricatorProjectColumn
   }
 
   public function getDisplayName() {
+    $proxy = $this->getProxy();
+    if ($proxy) {
+      return $proxy->getProxyColumnName();
+    }
+
     $name = $this->getName();
     if (strlen($name)) {
       return $name;
@@ -96,11 +117,23 @@ final class PhabricatorProjectColumn
     return null;
   }
 
+  public function getDisplayClass() {
+    $proxy = $this->getProxy();
+    if ($proxy) {
+      return $proxy->getProxyColumnClass();
+    }
+
+    return null;
+  }
+
   public function getHeaderIcon() {
-    $icon = null;
+    $proxy = $this->getProxy();
+    if ($proxy) {
+      return $proxy->getProxyColumnIcon();
+    }
 
     if ($this->isHidden()) {
-      $icon = 'fa-eye-slash';
+      return 'fa-eye-slash';
     }
 
     return null;

src/docs/user/userguide/projects.diviner

@@ -162,7 +162,6 @@ subprojects, parent projects, and milestones.
 |---|---|---|---|---|
 | //Members// | Yes | Union of Subprojects | Yes | Same as Parent |
 | //Policies// | Yes | Yes | Affected by Parent | Same as Parent |
-| //Workboard// | Yes | No Custom Columns | Yes | Yes |
 | //Hashtags// | Yes | Yes | Yes | Special |
 
 
@@ -257,14 +256,6 @@ parent project is an ancestor of the new subproject.
 You can edit the project afterward to change or remove members if you want to
 split membership apart in a more granular way across multiple new subprojects.
 
-**No Workboard Columns**: Parent projects can not have their own workboard
-columns: instead, the workboard of a parent project shows columns representing
-the child projects.
-
-Thus, a project's workboard columns are destroyed when you add the first
-subproject. All objects on the workboard will be returned to the project's
-backlog. The new board will show columns for subprojects instead.
-
 **Searching**: When you search for a parent project, results for any subproject
 are returned. For example, if you search for {nav Engineering}, your query will
 match results in {nav Engineering} itself, but also subprojects like

src/view/phui/PHUIWorkpanelView.php

@@ -10,8 +10,8 @@ final class PHUIWorkpanelView extends AphrontTagView {
   private $headerTag;
   private $headerIcon;
 
-  public function setHeaderIcon(PHUIIconView $header_icon) {
-    $this->headerIcon = $header_icon;
+  public function setHeaderIcon($icon) {
+    $this->headerIcon = $icon;
     return $this;
   }
 

webroot/rsrc/js/application/projects/behavior-project-boards.js

@@ -280,13 +280,16 @@ JX.behavior('project-boards', function(config, statics) {
         // close the dropdown, but don't want to follow the link.
         e.prevent();
 
-        var column_phid = e.getNodeData('column-add-task').columnPHID;
+        var column_data = e.getNodeData('column-add-task');
+        var column_phid = column_data.columnPHID;
+
         var request_data = {
           responseType: 'card',
           columnPHID: column_phid,
-          projects: statics.projectPHID,
+          projects: column_data.projectPHID,
           order: statics.order
         };
+
         var cols = getcolumns();
         var ii;
         var column;