Implement #yoloswag

Summary:
Ref T3190. #shipit

Likely future work:

  - Extract project mentions from remarkup for ApplicationTransactions; this isn't relevant in any apps right now (but will be in Pholio before tooo long). Ref T3189.
  - Allow projects to have alternate short names. As written, this is fine for most projects ("Differential" is `#differential`) but not so great for other projects ("Phabricator Public & Media Relations" is `#phabricator_public_media_relations`). This also breaks refs when you rename a project. Better would be letting long project names have short aliases (`#pr`) as permitted alternatives.

Since this mention uses `#` instead of a letter, I needed to do a small amount of regexp gymnastics.

Test Plan:
you only #yolo once

{F43615}

Reviewers: btrahan, chad

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T3189, T3190

Differential Revision: https://secure.phabricator.com/D5954

src/__phutil_library_map__.php

@@ -1714,6 +1714,7 @@ phutil_register_library_map(array(
     'PonderVotableView' => 'applications/ponder/view/PonderVotableView.php',
     'PonderVoteEditor' => 'applications/ponder/editor/PonderVoteEditor.php',
     'PonderVoteSaveController' => 'applications/ponder/controller/PonderVoteSaveController.php',
+    'ProjectRemarkupRule' => 'applications/project/remarkup/ProjectRemarkupRule.php',
     'QueryFormattingTestCase' => 'infrastructure/storage/__tests__/QueryFormattingTestCase.php',
     'ReleephActiveProjectListView' => 'applications/releeph/view/project/list/ReleephActiveProjectListView.php',
     'ReleephAuthorFieldSpecification' => 'applications/releeph/field/specification/ReleephAuthorFieldSpecification.php',
@@ -3504,6 +3505,7 @@ phutil_register_library_map(array(
     'PonderVotableView' => 'AphrontView',
     'PonderVoteEditor' => 'PhabricatorEditor',
     'PonderVoteSaveController' => 'PonderController',
+    'ProjectRemarkupRule' => 'PhabricatorRemarkupRuleObject',
     'QueryFormattingTestCase' => 'PhabricatorTestCase',
     'ReleephActiveProjectListView' => 'AphrontView',
     'ReleephAuthorFieldSpecification' => 'ReleephFieldSpecification',

src/applications/project/application/PhabricatorApplicationProject.php

@@ -26,6 +26,12 @@ final class PhabricatorApplicationProject extends PhabricatorApplication {
     return self::GROUP_ORGANIZATION;
   }
 
+  public function getRemarkupRules() {
+    return array(
+      new ProjectRemarkupRule(),
+    );
+  }
+
   public function getRoutes() {
     return array(
       '/project/' => array(

src/applications/project/remarkup/ProjectRemarkupRule.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @group project
+ */
+final class ProjectRemarkupRule
+  extends PhabricatorRemarkupRuleObject {
+
+  protected function getObjectNamePrefix() {
+    return '#';
+  }
+
+  protected function getObjectIDPattern() {
+    // NOTE: This explicitly does not match strings which contain only
+    // digits, because digit strings like "#123" are used to reference tasks at
+    // Facebook and are somewhat conventional in general.
+    return '[^\s.!,:;]*[^\s\d.!,:;]+[^\s.!,:;]*';
+  }
+
+  protected function loadObjects(array $ids) {
+    $viewer = $this->getEngine()->getConfig('viewer');
+
+    // If the user types "#YoloSwag", we still want to match "#yoloswag", so
+    // we normalize, query, and then map back to the original inputs.
+
+    $map = array();
+    foreach ($ids as $key => $slug) {
+      $map[PhabricatorSlug::normalize($slug)][] = $slug;
+    }
+
+    $projects = id(new PhabricatorProjectQuery())
+      ->setViewer($viewer)
+      ->withPhrictionSlugs(array_keys($map))
+      ->execute();
+
+    $result = array();
+    foreach ($projects as $project) {
+      $slugs = array($project->getPhrictionSlug());
+      foreach ($slugs as $slug) {
+        foreach ($map[$slug] as $original) {
+          $result[$original] = $project;
+        }
+      }
+    }
+
+
+    return $result;
+  }
+
+}

src/infrastructure/markup/rule/PhabricatorRemarkupRuleObject.php

@@ -99,11 +99,23 @@ abstract class PhabricatorRemarkupRuleObject
       array($this, 'markupObjectEmbed'),
       $text);
 
+    // If the prefix starts with a word character (like "D"), we want to
+    // require a word boundary so that we don't match "XD1" as "D1". If the
+    // prefix does not start with a word character, we want to require no word
+    // boundary for the same reasons. Test if the prefix starts with a word
+    // character.
+    if (preg_match('/^\w/', $prefix)) {
+      $boundary = '\\b';
+    } else {
+      $boundary = '\\B';
+    }
+
     // NOTE: The "(?<!#)" prevents us from linking "#abcdef" or similar. The
     // "\b" allows us to link "(abcdef)" or similar without linking things
     // in the middle of words.
+
     $text = preg_replace_callback(
-      '@(?<!#)\b'.$prefix.'('.$id.')(?:#([-\w\d]+))?\b@',
+      '((?<!#)'.$boundary.$prefix.'('.$id.')(?:#([-\w\d]+))?\b)',
       array($this, 'markupObjectReference'),
       $text);