Checking whether CIFS parent file is a valid path (Fixes #153)

src/main/java/com/xebialabs/overthere/cifs/CifsFile.java

@@ -66,7 +66,11 @@ public String getName() {
     @Override
     public OverthereFile getParentFile() {
         try {
-            return new CifsFile(getConnection(), new SmbFile(smbFile.getParent(), connection.authentication));
+            String parent = smbFile.getParent();
+            if (connection.encoder.isValidUncPath(parent)) {
+                return new CifsFile(getConnection(), new SmbFile(parent, connection.authentication));
+            }
+            return null;
         } catch (MalformedURLException exc) {
             return null;
         }

src/main/java/com/xebialabs/overthere/cifs/PathEncoder.java

@@ -110,4 +110,13 @@ final String fromUncPath(String uncPath) {
         return pathMapper.toLocalPath(matcher.group(1));
     }
 
+    /**
+     * Check whether the UNC path is valid.
+     * @param uncPath the UNC path to check.
+     * @return true if it is a valid UNC path.
+     */
+    final boolean isValidUncPath(String uncPath) {
+        return UNC_PATH_PATTERN.matcher(uncPath).matches();
+    }
+
 }

src/test/java/com/xebialabs/overthere/cifs/CifsFileTest.java

@@ -0,0 +1,44 @@
+package com.xebialabs.overthere.cifs;
+
+import com.xebialabs.overthere.ConnectionOptions;
+import com.xebialabs.overthere.OverthereFile;
+import com.xebialabs.overthere.cifs.winrm.CifsWinRmConnection;
+import org.testng.annotations.BeforeMethod;
+import org.testng.annotations.Test;
+
+import static com.xebialabs.overthere.ConnectionOptions.*;
+import static com.xebialabs.overthere.OperatingSystemFamily.WINDOWS;
+import static com.xebialabs.overthere.cifs.CifsConnectionBuilder.*;
+import static com.xebialabs.overthere.cifs.CifsConnectionType.WINRM_INTERNAL;
+import static com.xebialabs.overthere.util.DefaultAddressPortMapper.INSTANCE;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.nullValue;
+import static org.testng.Assert.*;
+
+public class CifsFileTest {
+
+    private ConnectionOptions options;
+
+    @BeforeMethod
+    public void setupOptions() {
+        options = new ConnectionOptions();
+        options.set(OPERATING_SYSTEM, WINDOWS);
+        options.set(CONNECTION_TYPE, WINRM_INTERNAL);
+        options.set(PASSWORD, "foobar");
+        options.set(PORT, PORT_DEFAULT_WINRM_HTTP);
+        options.set(CIFS_PORT, CIFS_PORT_DEFAULT);
+        options.set(ADDRESS, "localhost");
+    }
+
+
+    @Test
+    public void shouldReturnNullForParentFileOfRoot() {
+        options.set(USERNAME, "[email protected]");
+        CifsWinRmConnection cifsWinRmConnection = new CifsWinRmConnection(CIFS_PROTOCOL, options, INSTANCE);
+        OverthereFile file = cifsWinRmConnection.getFile("C:\\");
+        assertThat(file.getParentFile(), nullValue());
+    }
+
+
+}