diff --git a/src/applications/diffusion/controller/DiffusionBrowseSearchController.php b/src/applications/diffusion/controller/DiffusionBrowseSearchController.php
index 1070ec1bfd..76ff2553c9 100644
--- a/src/applications/diffusion/controller/DiffusionBrowseSearchController.php
+++ b/src/applications/diffusion/controller/DiffusionBrowseSearchController.php
@@ -52,39 +52,37 @@ final class DiffusionBrowseSearchController extends DiffusionBrowseController {
 
     $search_mode = null;
 
-    try {
-      if (strlen($this->getRequest()->getStr('grep'))) {
-        $search_mode = 'grep';
-        $query_string = $this->getRequest()->getStr('grep');
-        $results = $this->callConduitWithDiffusionRequest(
-          'diffusion.searchquery',
-          array(
-            'grep' => $query_string,
-            'commit' => $drequest->getStableCommit(),
-            'path' => $drequest->getPath(),
-            'limit' => $limit + 1,
-            'offset' => $page,
-          ));
-      } else { // Filename search.
-        $search_mode = 'find';
-        $query_string = $this->getRequest()->getStr('find');
-        $results = $this->callConduitWithDiffusionRequest(
-          'diffusion.querypaths',
-          array(
-            'pattern' => $query_string,
-            'commit' => $drequest->getStableCommit(),
-            'path' => $drequest->getPath(),
-            'limit' => $limit + 1,
-            'offset' => $page,
-          ));
-      }
-    } catch (ConduitException $ex) {
-      $err = $ex->getErrorDescription();
-      if ($err != '') {
-        return id(new PHUIErrorView())
-          ->setTitle(pht('Search Error'))
-          ->appendChild($err);
-      }
+    switch ($repository->getVersionControlSystem()) {
+      case PhabricatorRepositoryType::REPOSITORY_TYPE_SVN:
+        $results = array();
+        break;
+      default:
+        if (strlen($this->getRequest()->getStr('grep'))) {
+          $search_mode = 'grep';
+          $query_string = $this->getRequest()->getStr('grep');
+          $results = $this->callConduitWithDiffusionRequest(
+            'diffusion.searchquery',
+            array(
+              'grep' => $query_string,
+              'commit' => $drequest->getStableCommit(),
+              'path' => $drequest->getPath(),
+              'limit' => $limit + 1,
+              'offset' => $page,
+            ));
+        } else { // Filename search.
+          $search_mode = 'find';
+          $query_string = $this->getRequest()->getStr('find');
+          $results = $this->callConduitWithDiffusionRequest(
+            'diffusion.querypaths',
+            array(
+              'pattern' => $query_string,
+              'commit' => $drequest->getStableCommit(),
+              'path' => $drequest->getPath(),
+              'limit' => $limit + 1,
+              'offset' => $page,
+            ));
+        }
+        break;
     }
 
     $results = $pager->sliceResults($results);
diff --git a/src/applications/diffusion/controller/DiffusionCommitBranchesController.php b/src/applications/diffusion/controller/DiffusionCommitBranchesController.php
index ad3b5d8731..0be218fac8 100644
--- a/src/applications/diffusion/controller/DiffusionCommitBranchesController.php
+++ b/src/applications/diffusion/controller/DiffusionCommitBranchesController.php
@@ -8,22 +8,22 @@ final class DiffusionCommitBranchesController extends DiffusionController {
 
   protected function processDiffusionRequest(AphrontRequest $request) {
     $drequest = $this->getDiffusionRequest();
+    $repository = $drequest->getRepository();
 
-    $branches = array();
-    try {
-      $branches = $this->callConduitWithDiffusionRequest(
-        'diffusion.branchquery',
-        array(
-          'contains' => $drequest->getCommit(),
-        ));
-    } catch (ConduitException $ex) {
-      if ($ex->getMessage() != 'ERR-UNSUPPORTED-VCS') {
-        throw $ex;
-      }
+    switch ($repository->getVersionControlSystem()) {
+      case PhabricatorRepositoryType::REPOSITORY_TYPE_SVN:
+        $branches = array();
+        break;
+      default:
+        $branches = $this->callConduitWithDiffusionRequest(
+          'diffusion.branchquery',
+          array(
+            'contains' => $drequest->getCommit(),
+          ));
+        break;
     }
 
     $branches = DiffusionRepositoryRef::loadAllFromDictionaries($branches);
-
     $branch_links = array();
     foreach ($branches as $branch) {
       $branch_links[] = phutil_tag(
diff --git a/src/applications/diffusion/controller/DiffusionCommitTagsController.php b/src/applications/diffusion/controller/DiffusionCommitTagsController.php
index 22fcf4907e..3c698f9a70 100644
--- a/src/applications/diffusion/controller/DiffusionCommitTagsController.php
+++ b/src/applications/diffusion/controller/DiffusionCommitTagsController.php
@@ -8,23 +8,23 @@ final class DiffusionCommitTagsController extends DiffusionController {
 
   protected function processDiffusionRequest(AphrontRequest $request) {
     $drequest = $this->getDiffusionRequest();
+    $repository = $drequest->getRepository();
+
     $tag_limit = 10;
-
-    $tags = array();
-    try {
-      $tags = DiffusionRepositoryTag::newFromConduit(
-        $this->callConduitWithDiffusionRequest(
-          'diffusion.tagsquery',
-          array(
-            'commit' => $drequest->getCommit(),
-            'limit' => $tag_limit + 1,
-          )));
-    } catch (ConduitException $ex) {
-      if ($ex->getMessage() != 'ERR-UNSUPPORTED-VCS') {
-        throw $ex;
-      }
+    switch ($repository->getVersionControlSystem()) {
+      case PhabricatorRepositoryType::REPOSITORY_TYPE_SVN:
+        $tags = array();
+        break;
+      default:
+        $tags = DiffusionRepositoryTag::newFromConduit(
+          $this->callConduitWithDiffusionRequest(
+            'diffusion.tagsquery',
+            array(
+              'commit' => $drequest->getCommit(),
+              'limit' => $tag_limit + 1,
+            )));
+        break;
     }
-
     $has_more_tags = (count($tags) > $tag_limit);
     $tags = array_slice($tags, 0, $tag_limit);
 
diff --git a/src/applications/diffusion/controller/DiffusionRepositoryController.php b/src/applications/diffusion/controller/DiffusionRepositoryController.php
index f0fd121719..873895d329 100644
--- a/src/applications/diffusion/controller/DiffusionRepositoryController.php
+++ b/src/applications/diffusion/controller/DiffusionRepositoryController.php
@@ -374,23 +374,23 @@ final class DiffusionRepositoryController extends DiffusionController {
 
   private function buildTagListTable(DiffusionRequest $drequest) {
     $viewer = $this->getRequest()->getUser();
+    $repository = $drequest->getRepository();
 
+    switch ($repository->getVersionControlSystem()) {
+      case PhabricatorRepositoryType::REPOSITORY_TYPE_SVN:
+        // no tags in SVN
+        return null;
+    }
     $tag_limit = 15;
     $tags = array();
-    try {
-      $tags = DiffusionRepositoryTag::newFromConduit(
-        $this->callConduitWithDiffusionRequest(
-          'diffusion.tagsquery',
-          array(
-            // On the home page, we want to find tags on any branch.
-            'commit' => null,
-            'limit' => $tag_limit + 1,
-          )));
-    } catch (ConduitException $e) {
-      if ($e->getMessage() != 'ERR-UNSUPPORTED-VCS') {
-        throw $e;
-      }
-    }
+    $tags = DiffusionRepositoryTag::newFromConduit(
+      $this->callConduitWithDiffusionRequest(
+        'diffusion.tagsquery',
+        array(
+          // On the home page, we want to find tags on any branch.
+          'commit' => null,
+          'limit' => $tag_limit + 1,
+        )));
 
     if (!$tags) {
       return null;
@@ -402,7 +402,7 @@ final class DiffusionRepositoryController extends DiffusionController {
     $commits = id(new DiffusionCommitQuery())
       ->setViewer($viewer)
       ->withIdentifiers(mpull($tags, 'getCommitIdentifier'))
-      ->withRepository($drequest->getRepository())
+      ->withRepository($repository)
       ->needCommitData(true)
       ->execute();
 
diff --git a/src/applications/diffusion/controller/DiffusionTagListController.php b/src/applications/diffusion/controller/DiffusionTagListController.php
index f89215cc8c..bf2c2f84ce 100644
--- a/src/applications/diffusion/controller/DiffusionTagListController.php
+++ b/src/applications/diffusion/controller/DiffusionTagListController.php
@@ -28,16 +28,16 @@ final class DiffusionTagListController extends DiffusionController {
       $is_commit = false;
     }
 
-    $tags = array();
-    try {
-      $conduit_result = $this->callConduitWithDiffusionRequest(
-        'diffusion.tagsquery',
-        $params);
-      $tags = DiffusionRepositoryTag::newFromConduit($conduit_result);
-    } catch (ConduitException $ex) {
-      if ($ex->getMessage() != 'ERR-UNSUPPORTED-VCS') {
-        throw $ex;
-      }
+    switch ($repository->getVersionControlSystem()) {
+      case PhabricatorRepositoryType::REPOSITORY_TYPE_SVN:
+        $tags = array();
+        break;
+      default:
+        $conduit_result = $this->callConduitWithDiffusionRequest(
+          'diffusion.tagsquery',
+          $params);
+        $tags = DiffusionRepositoryTag::newFromConduit($conduit_result);
+        break;
     }
     $tags = $pager->sliceResults($tags);