testcase for concat's overwrite attribute

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@943072 13f79535-47bb-0310-9956-ffa450edef68

src/etc/testcases/taskdefs/concat.xml

@@ -115,6 +115,15 @@
     </concat>
   </target>
 
+  <target name="testoverwrite">
+    <touch file="${tmp.file.2}"/>
+    <!-- concat.xml is now older than tmp.file.2
+         so the following should still overwrite it -->
+    <concat destfile="${tmp.file.2}" overwrite="true">
+      <path path="concat.xml"/>
+    </concat>
+  </target>
+
   <target name="testheaderfooter">
     <concat>
       <header filtering="false" trim="yes">

src/tests/junit/org/apache/tools/ant/taskdefs/ConcatTest.java

@@ -178,6 +178,13 @@ public class ConcatTest
         assertEquals(size, 0);
     }
 
+    public void testOverwrite() {
+        executeTarget("testoverwrite");
+        File file2 = new File(getProjectDir(), tempFile2);
+        long size = file2.length();
+        assertTrue(size > 0);
+    }
+
     public void testheaderfooter() {
         test3();
         expectLog("testheaderfooter", "headerHello, World!footer");