add a filter for native2ascii

WHATSNEW

@@ -44,6 +44,9 @@ Other changes:
    removed from the JDK.
    Bugzilla Report 59855
 
+ * added a new <native2asciifilter> filter that can perform non-ASCII
+   to Unicode-escape conversions.
+
 Changes from Ant 1.9.6 TO Ant 1.9.7
 ===================================
 

manual/Types/filterchain.html

@@ -1143,6 +1143,7 @@ and \\.
         <a href="#ignoreblank">IgnoreBlank</a><br>
         <a href="#filterdeletecharacters">DeleteCharacters</a><br>
         <a href="#uniqfilter">UniqFilter</a><br>
+        <a href="#native2asciifilter">Native2AsciiFilter</a><br>
     </p>
 
     The following string filters are provided by the optional distribution.
@@ -1487,6 +1488,39 @@ This suppresses duplicate lines.
 &lt;/tokenfilter&gt;
 </pre></blockquote>
 
+<p><b><em><a name="native2asciifilter">Native2AsciiFilter</a></em></b></p>
+
+<p>Uses the "builtin" implementation of
+  the <a href="../Tasks/native2ascii.html">native2ascii</a> task.</p>
+
+<p>Replaces non-ascii characters by their Unicode-escapes or
+  vice-versa.  <em>Since Ant 1.9.8</em>.</p>
+
+<p>This filter may be used directly within a filterchain.</p>
+
+<table cellSpacing=0 cellPadding=2 border=1>
+  <tr>
+    <td vAlign=top><b>Attribute</b></td>
+    <td vAlign=top><b>Description</b></td>
+    <td vAlign=top align="center"><b>Required</b></td>
+  </tr>
+  <tr>
+    <td vAlign=top>reverse</td>
+    <td vAlign=top>Reverse the sense of the conversion,
+      i.e. convert from ASCII to native.</td>
+    <td vAlign=top align="center">No</td>
+  </tr>
+</table>
+
+<h4>Example:</h4>
+
+<p>This replaces all non-ASCII characters by their Unicode-escapes.</p>
+<blockquote><pre>
+&lt;tokenfilter&gt;
+  &lt;native2asciifilter/&gt;
+&lt;/tokenfilter&gt;
+</pre></blockquote>
+
 <p><b><em><a name="scriptfilter">ScriptFilter</a></em></b></p>
 This is an optional filter that executes a script in a
 <a href="http://jakarta.apache.org/bsf" target="_top">Apache BSF</a>

src/main/org/apache/tools/ant/antlib.xml

@@ -140,5 +140,7 @@
                 classname="org.apache.tools.ant.filters.SortFilter"/>
   <componentdef name="uniqfilter" onerror="ignore"
                 classname="org.apache.tools.ant.filters.UniqFilter"/>
+  <componentdef name="native2asciifilter" onerror="ignore"
+                classname="org.apache.tools.ant.filters.Native2AsciiFilter"/>
 </antlib>
 

src/main/org/apache/tools/ant/filters/Native2AsciiFilter.java

@@ -0,0 +1,47 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+package org.apache.tools.ant.filters;
+
+import org.apache.tools.ant.util.Native2AsciiUtils;
+
+/**
+ * A filter that performs translations from characters to their
+ * Unicode-escape sequences and vice-versa.
+ *
+ * @since Ant 1.9.8
+ */
+public class Native2AsciiFilter extends TokenFilter.ChainableReaderFilter {
+    private boolean reverse;
+
+    /**
+     * Flag the conversion to run in the reverse sense,
+     * that is Ascii to Native encoding.
+     *
+     * @param reverse True if the conversion is to be reversed,
+     *                otherwise false;
+     */
+    public void setReverse(boolean reverse) {
+        this.reverse = reverse;
+    }
+
+    public String filter(String line) {
+        return reverse
+            ? Native2AsciiUtils.ascii2native(line)
+            : Native2AsciiUtils.native2ascii(line);
+    }
+}

src/tests/antunit/filters/native2ascii-test.xml

@@ -0,0 +1,53 @@
+<?xml version="1.0"?>
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+  -->
+<project default="antunit" xmlns:au="antlib:org.apache.ant.antunit">
+  <import file="../antunit-base.xml" />
+
+  <target name="testForward">
+    <au:assertTrue>
+      <resourcesmatch>
+        <string value="\u00e4\u00f6\u00fc=\u00c4\u00d6\u00dc
+\u00df=\u20ac"/>
+        <concat>
+          <string value="äöü=ÄÖÜ
+ß=€"/>
+          <filterchain>
+            <native2asciifilter/>
+          </filterchain>
+        </concat>
+      </resourcesmatch>
+    </au:assertTrue>
+  </target>
+
+  <target name="testReverse">
+    <au:assertTrue>
+      <resourcesmatch>
+        <string value="äöü=ÄÖÜ
+ß=€"/>
+        <concat>
+          <string value="\u00e4\u00f6\u00fc=\u00c4\u00d6\u00dc
+\u00df=\u20ac"/>
+          <filterchain>
+            <native2asciifilter reverse="true"/>
+          </filterchain>
+        </concat>
+      </resourcesmatch>
+    </au:assertTrue>
+  </target>
+
+</project>