diff --git a/smb/CMakeLists.txt b/smb/CMakeLists.txt
--- a/smb/CMakeLists.txt
+++ b/smb/CMakeLists.txt
@@ -73,3 +73,5 @@
 install(TARGETS kio_smb DESTINATION ${KDE_INSTALL_PLUGINDIR}/kf5/kio)
 install(FILES smb-network.desktop DESTINATION ${KDE_INSTALL_DATADIR}/konqueror/dirtree/remote)
 install(FILES smb-network.desktop DESTINATION ${KDE_INSTALL_DATADIR}/remoteview)
+
+add_subdirectory(autotests)
diff --git a/smb/autotests/CMakeLists.txt b/smb/autotests/CMakeLists.txt
new file mode 100644
--- /dev/null
+++ b/smb/autotests/CMakeLists.txt
@@ -0,0 +1,17 @@
+if(NOT BUILD_TESTING)
+    return()
+endif()
+
+# allow coercing cstring to qstring, easier to write
+remove_definitions(-DQT_NO_CAST_FROM_ASCII)
+
+find_package(Qt5Test ${QT_MIN_VERSION} CONFIG REQUIRED)
+
+include(ECMAddTests)
+
+ecm_add_tests(
+    smburltest
+    LINK_LIBRARIES
+        Qt5::Test
+        kio_smb_static
+)
diff --git a/smb/autotests/smburltest.cpp b/smb/autotests/smburltest.cpp
new file mode 100644
--- /dev/null
+++ b/smb/autotests/smburltest.cpp
@@ -0,0 +1,69 @@
+/*
+    SPDX-FileCopyrightText: 2020 Harald Sitter <sitter@kde.org>
+    SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+*/
+
+#include <QTest>
+#include <QAbstractItemModelTester>
+
+#include "smburl.h"
+
+class SMBUrlTest : public QObject
+{
+    Q_OBJECT
+private Q_SLOTS:
+    void testMinimalToSmbcValid()
+    {
+        // libsmbclient is a bit picky. make sure we convert to minimal applicable form
+        {
+            SMBUrl url(QUrl("smb:/"));
+            QCOMPARE(url.toSmbcUrl(), "smb://");
+        }
+
+        // But at the same time it will happily deal with smb:
+        {
+            SMBUrl url(QUrl("smb:"));
+            QCOMPARE(url.toSmbcUrl(), "smb:");
+        }
+    }
+
+    void testType()
+    {
+        QCOMPARE(SMBUrl(QUrl("smb://")).getType(), SMBURLTYPE_ENTIRE_NETWORK);
+        QCOMPARE(SMBUrl(QUrl("smb://host")).getType(), SMBURLTYPE_WORKGROUP_OR_SERVER);
+        QCOMPARE(SMBUrl(QUrl("smb://host/share/file")).getType(), SMBURLTYPE_SHARE_OR_PATH);
+        QCOMPARE(SMBUrl(QUrl()).getType(), SMBURLTYPE_UNKNOWN);
+    }
+
+    void testPart()
+    {
+        SMBUrl url(QUrl("smb://host/share/file"));
+        QCOMPARE(url.partUrl().toString(), "smb://host/share/file.part");
+    }
+
+    void testUp()
+    {
+        SMBUrl url(QUrl("smb://host/share/file"));
+        url.cdUp();
+        QCOMPARE(url.toSmbcUrl(), "smb://host/share");
+    }
+
+    void testAddPath()
+    {
+        SMBUrl url(QUrl("smb://host/share"));
+        url.addPath("file");
+        QCOMPARE(url.toSmbcUrl(), "smb://host/share/file");
+    }
+
+    void testCifs()
+    {
+        // We treat cifs as an alias but need to translate it to smb.
+        // https://bugs.kde.org/show_bug.cgi?id=327295
+        SMBUrl url(QUrl("cifs://host/share/file"));
+        QCOMPARE(url.toSmbcUrl(), "smb://host/share/file");
+    }
+};
+
+QTEST_GUILESS_MAIN(SMBUrlTest)
+
+#include "smburltest.moc"
diff --git a/smb/kio_smb_browse.cpp b/smb/kio_smb_browse.cpp
--- a/smb/kio_smb_browse.cpp
+++ b/smb/kio_smb_browse.cpp
@@ -422,7 +422,7 @@
                     // Call base class to list entry
                     listEntry(udsentry);
                 }
-                m_current_url.cd("..");
+                m_current_url.cdUp();
             } else if (dirp->smbc_type == SMBC_SERVER || dirp->smbc_type == SMBC_FILE_SHARE) {
                 // Set type
                 udsentry.fastInsert(KIO::UDSEntry::UDS_FILE_TYPE, S_IFDIR);
diff --git a/smb/smburl.h b/smb/smburl.h
--- a/smb/smburl.h
+++ b/smb/smburl.h
@@ -68,7 +68,7 @@
      */
     void addPath(const QString &filedir);
 
-    bool cd(const QString &dir);
+    void cdUp();
 
     /**
      *   Returns the type of this SMBUrl:
diff --git a/smb/smburl.cpp b/smb/smburl.cpp
--- a/smb/smburl.cpp
+++ b/smb/smburl.cpp
@@ -64,15 +64,10 @@
     updateCache();
 }
 
-bool SMBUrl::cd(const QString &filedir)
+void SMBUrl::cdUp()
 {
-    if (filedir == "..") {
-        setUrl(KIO::upUrl(*this).url());
-    } else {
-        setUrl(filedir);
-    }
+    setUrl(KIO::upUrl(*this).url());
     updateCache();
-    return true;
 }
 
 void SMBUrl::updateCache()