Allow inline comments to be individually hidden

Summary:
Ref T7447. Implements per-viewer comment hiding. Once a comment is obsolete or uninteresting, you can hide it completely.

This is sticky per-user.

My hope is that this will strike a better balance between concerns than some of the other approaches (conservative porting, summarization, hide-all).

Specifically, this adds a new action here:

{F435621}

Clicking it completely collapses the comment into a small icon on the previous line, and saves the comment state as hidden for you:

{F435626}

You can click the icon to reveal all hidden comments below the line.

Test Plan:
  - Hid comments.
  - Showed comments.
  - Created, edited, deleted and submitted comments.
  - Used Diffusion comments (hiding is not implemented there yet, but I'd plan to bring it there eventually if it works out in Differential).

Reviewers: btrahan, chad

Reviewed By: btrahan

Subscribers: jparise, yelirekim, epriestley

Maniphest Tasks: T7447

Differential Revision: https://secure.phabricator.com/D13009

src/applications/differential/controller/DifferentialChangesetViewController.php

@@ -191,6 +191,7 @@ final class DifferentialChangesetViewController extends DifferentialController {
     if ($revision) {
       $query = id(new DifferentialInlineCommentQuery())
         ->setViewer($viewer)
+        ->needHidden(true)
         ->withRevisionPHIDs(array($revision->getPHID()));
       $inlines = $query->execute();
       $inlines = $query->adjustInlinesForChangesets(

src/applications/differential/controller/DifferentialInlineCommentEditController.php

@@ -42,6 +42,7 @@ final class DifferentialInlineCommentEditController
       ->setViewer($this->getViewer())
       ->withIDs(array($id))
       ->withDeletedDrafts(true)
+      ->needHidden(true)
       ->executeOne();
   }
 
@@ -50,6 +51,7 @@ final class DifferentialInlineCommentEditController
       ->setViewer($this->getViewer())
       ->withPHIDs(array($phid))
       ->withDeletedDrafts(true)
+      ->needHidden(true)
       ->executeOne();
   }
 
@@ -152,4 +154,38 @@ final class DifferentialInlineCommentEditController
     return $this->loadRevision()->getAuthorPHID();
   }
 
+  protected function hideComments(array $ids) {
+    $viewer = $this->getViewer();
+    $table = new DifferentialHiddenComment();
+    $conn_w = $table->establishConnection('w');
+
+    $sql = array();
+    foreach ($ids as $id) {
+      $sql[] = qsprintf(
+        $conn_w,
+        '(%s, %d)',
+        $viewer->getPHID(),
+        $id);
+    }
+
+    queryfx(
+      $conn_w,
+      'INSERT IGNORE INTO %T (userPHID, commentID) VALUES %Q',
+      $table->getTableName(),
+      implode(', ', $sql));
+  }
+
+  protected function showComments(array $ids) {
+    $viewer = $this->getViewer();
+    $table = new DifferentialHiddenComment();
+    $conn_w = $table->establishConnection('w');
+
+    queryfx(
+      $conn_w,
+      'DELETE FROM %T WHERE userPHID = %s AND commentID IN (%Ld)',
+      $table->getTableName(),
+      $viewer->getPHID(),
+      $ids);
+  }
+
 }

src/applications/differential/controller/DifferentialInlineCommentPreviewController.php

@@ -19,6 +19,7 @@ extends PhabricatorInlineCommentPreviewController {
       ->withDrafts(true)
       ->withAuthorPHIDs(array($viewer->getPHID()))
       ->withRevisionPHIDs(array($revision->getPHID()))
+      ->needHidden(true)
       ->execute();
   }
 

src/applications/differential/controller/DifferentialRevisionViewController.php

@@ -175,6 +175,7 @@ final class DifferentialRevisionViewController extends DifferentialController {
 
       $query = id(new DifferentialInlineCommentQuery())
         ->setViewer($user)
+        ->needHidden(true)
         ->withRevisionPHIDs(array($revision->getPHID()));
       $inlines = $query->execute();
       $inlines = $query->adjustInlinesForChangesets(