Only link symbols if there might be any

Summary:
fixes T8260. Only turn on symbol links if:
- The repository has any configuration about symbols, or
- There actually are symbols in the repository.

Test Plan: Look at revisions and files in various states of configurations and having symbols.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: joshuaspence, Korvin, epriestley

Maniphest Tasks: T8260

Differential Revision: https://secure.phabricator.com/D12946

src/applications/differential/controller/DifferentialRevisionViewController.php

@@ -261,12 +261,11 @@ final class DifferentialRevisionViewController extends DifferentialController {
 
     $repository = $revision->getRepository();
     if ($repository) {
-      list($symbol_indexes, $repository_phids) = $this->buildSymbolIndexes(
+      $symbol_indexes = $this->buildSymbolIndexes(
         $repository,
         $visible_changesets);
     } else {
       $symbol_indexes = array();
-      $repository_phids = null;
     }
 
     $revision_detail->setActions($actions);
@@ -306,15 +305,6 @@ final class DifferentialRevisionViewController extends DifferentialController {
       ),
       $comment_view);
 
-    if ($repository) {
-      Javelin::initBehavior(
-        'repository-crossreference',
-        array(
-          'section' => $wrap_id,
-          'repositories' => $repository_phids,
-        ));
-    }
-
     $changeset_view = new DifferentialChangesetListView();
     $changeset_view->setChangesets($changesets);
     $changeset_view->setVisibleChangesets($visible_changesets);
@@ -758,11 +748,22 @@ final class DifferentialRevisionViewController extends DifferentialController {
     $langs = $repository->getSymbolLanguages();
     $langs = nonempty($langs, array());
 
+    $sources = $repository->getSymbolSources();
+    $sources = nonempty($sources, array());
+
     $symbol_indexes = array();
 
+    if ($langs && $sources) {
+      $have_symbols = id(new DiffusionSymbolQuery())
+          ->existsSymbolsInRepository($repository->getPHID());
+      if (!$have_symbols) {
+        return $symbol_indexes;
+      }
+    }
+
     $repository_phids = array_merge(
       array($repository->getPHID()),
-      nonempty($repository->getSymbolSources(), array()));
+      $sources);
 
     $indexed_langs = array_fill_keys($langs, true);
     foreach ($visible_changesets as $key => $changeset) {
@@ -775,7 +776,7 @@ final class DifferentialRevisionViewController extends DifferentialController {
       }
     }
 
-    return array($symbol_indexes, $repository_phids);
+    return $symbol_indexes;
   }
 
   private function loadOtherRevisions(

src/applications/diffusion/controller/DiffusionBrowseFileController.php

@@ -267,13 +267,28 @@ final class DiffusionBrowseFileController extends DiffusionBrowseController {
       $id = celerity_generate_unique_node_id();
 
       $repo = $drequest->getRepository();
-      $symbol_repos = $repo->getSymbolSources();
+      $symbol_repos = nonempty($repo->getSymbolSources(), array());
       $symbol_repos[] = $repo;
 
       $lang = last(explode('.', $drequest->getPath()));
       $repo_languages = $repo->getSymbolLanguages();
+      $repo_languages = nonempty($repo_languages, array());
       $repo_languages = array_fill_keys($repo_languages, true);
-      if (empty($repo_languages) || isset($repo_languages[$lang])) {
+
+      $needs_symbols = true;
+      if ($repo_languages && $symbol_repos) {
+        $have_symbols = id(new DiffusionSymbolQuery())
+            ->existsSymbolsInRepository($repo->getPHID());
+        if (!$have_symbols) {
+          $needs_symbols = false;
+        }
+      }
+
+      if ($needs_symbols && $repo_languages) {
+        $needs_symbols = isset($repo_languages[$lang]);
+      }
+
+      if ($needs_symbols) {
         Javelin::initBehavior(
           'repository-crossreference',
           array(

src/applications/diffusion/query/DiffusionSymbolQuery.php

@@ -113,6 +113,26 @@ final class DiffusionSymbolQuery extends PhabricatorOffsetPagedQuery {
   }
 
 
+/* -(  Specialized Query  )-------------------------------------------------- */
+
+  public function existsSymbolsInRepository($repository_phid) {
+    $this
+      ->withRepositoryPHIDs(array($repository_phid))
+      ->setLimit(1);
+
+    $symbol = new PhabricatorRepositorySymbol();
+    $conn_r = $symbol->establishConnection('r');
+
+    $data = queryfx_all(
+      $conn_r,
+      'SELECT * FROM %T %Q %Q',
+      $symbol->getTableName(),
+      $this->buildWhereClause($conn_r),
+      $this->buildLimitClause($conn_r));
+
+    return (!empty($data));
+  }
+
 /* -(  Executing the Query  )------------------------------------------------ */