Introduce "local names" for commits

Summary: Ref T4245. Full commit display names (like `rPaaaa`) are going to be obnoxious soon in some cases (e.g., `rPaaaa` becomes `R123:aaaa`, which is much uglier) so reduce how often we show the repository in cases where it isn't really necessary to include it.

Test Plan:
  - Saw no more `rX` on repository list view for Git/Mercurial (still present for Subversion).
  - Saw no more `rX` on various repository detail views, except when referencing other commits (e.g., mentions).
  - Grepped for removed `getShortName()`.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T4245

Differential Revision: https://secure.phabricator.com/D14990

src/applications/diffusion/controller/DiffusionBrowseController.php

@@ -1761,7 +1761,7 @@ final class DiffusionBrowseController extends DiffusionController {
             'size'  => 600,
           ),
         ),
-        $commit->getShortName());
+        $commit->getLocalName());
 
       $links[$identifier] = $commit_link;
     }

src/applications/diffusion/view/DiffusionView.php

@@ -128,7 +128,7 @@ abstract class DiffusionView extends AphrontView {
     $commit,
     $summary = '') {
 
-    $commit_name = $repository->formatCommitName($commit);
+    $commit_name = $repository->formatCommitName($commit, $local = true);
 
     if (strlen($summary)) {
       $commit_name .= ': '.$summary;

src/applications/repository/query/PhabricatorRepositorySearchEngine.php

@@ -160,10 +160,16 @@ final class PhabricatorRepositorySearchEngine
 
       $commit = $repository->getMostRecentCommit();
       if ($commit) {
-        $commit_link = DiffusionView::linkCommit(
-          $repository,
-          $commit->getCommitIdentifier(),
-          $commit->getSummary());
+        $commit_link = phutil_tag(
+          'a',
+          array(
+            'href' => $commit->getURI(),
+          ),
+          pht(
+            '%s: %s',
+            $commit->getLocalName(),
+            $commit->getSummary()));
+
         $item->setSubhead($commit_link);
         $item->setEpoch($commit->getEpoch());
       }

src/applications/repository/storage/PhabricatorRepository.php

@@ -924,7 +924,7 @@ final class PhabricatorRepository extends PhabricatorRepositoryDAO
     return $this->isBranchInFilter($branch, 'branch-filter');
   }
 
-  public function formatCommitName($commit_identifier) {
+  public function formatCommitName($commit_identifier, $local = false) {
     $vcs = $this->getVersionControlSystem();
 
     $type_git = PhabricatorRepositoryType::REPOSITORY_TYPE_GIT;
@@ -933,12 +933,23 @@ final class PhabricatorRepository extends PhabricatorRepositoryDAO
     $is_git = ($vcs == $type_git);
     $is_hg = ($vcs == $type_hg);
     if ($is_git || $is_hg) {
-      $short_identifier = substr($commit_identifier, 0, 12);
+      $name = substr($commit_identifier, 0, 12);
+      $need_scope = false;
     } else {
-      $short_identifier = $commit_identifier;
+      $name = $commit_identifier;
+      $need_scope = true;
     }
 
-    return 'r'.$this->getCallsign().$short_identifier;
+    if (!$local) {
+      $need_scope = true;
+    }
+
+    if ($need_scope) {
+      $scope = 'r'.$this->getCallsign();
+      $name = $scope.$name;
+    }
+
+    return $name;
   }
 
   public function isImporting() {

src/applications/repository/storage/PhabricatorRepositoryCommit.php

@@ -266,9 +266,20 @@ final class PhabricatorRepositoryCommit
     return $repository->formatCommitName($identifier);
   }
 
-  public function getShortName() {
+  /**
+   * Return a local display name for use in the context of the containing
+   * repository.
+   *
+   * In Git and Mercurial, this returns only a short hash, like "abcdef012345".
+   * See @{method:getDisplayName} for a short name that always includes
+   * repository context.
+   *
+   * @return string Short human-readable name for use inside a repository.
+   */
+  public function getLocalName() {
+    $repository = $this->getRepository();
     $identifier = $this->getCommitIdentifier();
-    return substr($identifier, 0, 9);
+    return $repository->formatCommitName($identifier, $local = true);
   }
 
   public function renderAuthorLink($handles) {