If a fileset defines a single file, allow the Copy and Move tasks to work with the toFile attribute.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@269779 13f79535-47bb-0310-9956-ffa450edef68

docs/manual/CoreTasks/copy.html

@@ -39,7 +39,9 @@ To use a fileset, the <var>todir</var> attribute must be set.</p>
     <td valign="top">The file to copy to.</td>
     <td valign="top" align="center" rowspan="2">With the <var>file</var> attribute, 
     either <var>tofile</var> or <var>todir</var> can be used.  With nested filesets, 
-    only <var>todir</var> is allowed.</td>
+    if the fileset size is greater than 1 or if the only entry in the fileset is a
+    directory or if the file attribute is already specified, only
+    <var>todir</var> is allowed</td>
   </tr>
   <tr>
     <td valign="top">todir</td>

src/main/org/apache/tools/ant/taskdefs/Copy.java

@@ -74,6 +74,7 @@ import java.util.*;
  * @author Glenn McAllister <a href="mailto:glennm@ca.ibm.com">glennm@ca.ibm.com</a>
  * @author <a href="mailto:stefan.bodewig@epost.de">Stefan Bodewig</a>
  * @author <A href="gholam@xtra.co.nz">Michael McCallum</A>
+ * @author <a href="mailto:umagesh@rediffmail.com">Magesh Umasankar</a>
  */
 public class Copy extends Task {
     protected File file = null;     // the source file 
@@ -287,7 +288,27 @@ public class Copy extends Task {
         }
            
         if (destFile != null && filesets.size() > 0) {
-            throw new BuildException("Cannot concatenate multple files into a single file.");
+            if (filesets.size() > 1) {
+                throw new BuildException(
+                    "Cannot concatenate multiple files into a single file.");
+            } else {
+                FileSet fs = (FileSet) filesets.elementAt(0);
+                DirectoryScanner ds = fs.getDirectoryScanner(project);
+                String[] srcFiles = ds.getIncludedFiles();
+
+                if (srcFiles.length > 0) {
+                    if (file == null) {
+                        file = new File(srcFiles[0]);
+                        filesets.removeElementAt(0);
+                    } else {
+                        throw new BuildException(
+                            "Cannot concatenate multiple files into a single file.");
+                    }
+                } else {
+                    throw new BuildException(
+                        "Cannot perform operation from directory to file.");
+                }
+            }
         }
 
         if (destFile != null) {