Index: plugins/clang/tests/test_assistants.cpp
===================================================================
--- plugins/clang/tests/test_assistants.cpp
+++ plugins/clang/tests/test_assistants.cpp
@@ -96,7 +96,10 @@
     file.open(QIODevice::WriteOnly | QIODevice::Text);
     file.write(fileContents.toUtf8());
     file.close();
-    return QUrl::fromLocalFile(file.fileName());
+    // Generate and return a QUrl from the file's canonical name; this prevents 
+    // DocumentController problems when QTemporaryDir returns a path containing
+    // a symlink (will likely be the case on Mac).
+    return QUrl::fromLocalFile(QFileInfo(file.fileName()).canonicalFilePath());
 }
 
 class Testbed
@@ -200,7 +203,13 @@
     {
         Core::self()->documentController()->openDocument(url);
         DUChain::self()->waitForUpdate(IndexedString(url), KDevelop::TopDUContext::AllDeclarationsAndContexts);
-        return Core::self()->documentController()->documentForUrl(url)->textDocument();
+        const auto doc = Core::self()->documentController()->documentForUrl(url);
+        if (doc) {
+            return doc->textDocument();
+        } else {
+            qCritical() << "DocumentController:documentForUrl() returns NULL for" << url;
+            return nullptr;
+        }
     }
 
     IncludeBehavior m_includeBehavior;