diff --git a/src/repository/api/ArcanistGitAPI.php b/src/repository/api/ArcanistGitAPI.php
index b7a045cb..8e3b8065 100644
--- a/src/repository/api/ArcanistGitAPI.php
+++ b/src/repository/api/ArcanistGitAPI.php
@@ -702,6 +702,14 @@ final class ArcanistGitAPI extends ArcanistRepositoryAPI {
     return rtrim($stdout, "\n");
   }
 
+  public function getUnderlyingWorkingCopyRevision() {
+    list($err, $stdout) = $this->execManualLocal('svn find-rev HEAD');
+    if (!$err && $stdout) {
+      return rtrim($stdout, "\n");
+    }
+    return $this->getWorkingCopyRevision();
+  }
+
   public function isHistoryDefaultImmutable() {
     return false;
   }
diff --git a/src/repository/api/ArcanistRepositoryAPI.php b/src/repository/api/ArcanistRepositoryAPI.php
index 82f9fdcb..0e4334e5 100644
--- a/src/repository/api/ArcanistRepositoryAPI.php
+++ b/src/repository/api/ArcanistRepositoryAPI.php
@@ -173,6 +173,10 @@ abstract class ArcanistRepositoryAPI {
     ConduitClient $conduit,
     array $query);
 
+  public function getUnderlyingWorkingCopyRevision() {
+    return $this->getWorkingCopyRevision();
+  }
+
   /**
    * Set the base commit to a reasonable default value so that working copy
    * status checks can do something meaningful and won't invoke configured