Add a mapper similar to wget --cut-dirs, based on user-list discussion initiated by Michael Ludwig

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@998962 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -203,6 +203,9 @@ Other changes:
    and singleline attributes.
    Bugzilla Report 49764.
 
+ * A new <cutdirsmapper> can be used like wget's --cut-dirs option to
+   strip leading directories from file names.
+
 Changes from Ant 1.8.0 TO Ant 1.8.1 
 ===================================
 

docs/manual/Types/mapper.html

@@ -919,7 +919,44 @@ list of mapped names reset after every invocation.
     <code>&lt;mapper <b>type</b>&gt;</code> attribute.
   </p>
 
+<h4><a name="cutdirs-mapper">cutdirsmapper (since Ant 1.8.2)</a></h4>
 
+<p>This mapper strips a configured number of leading directories from
+  the source file name.</p>
+
+<b>Examples:</b>
+<blockquote><pre>
+&lt;cutdirsmapper dirs="1"/&gt;
+</pre></blockquote>
+
+<table border="1" cellpadding="2" cellspacing="0">
+  <tr>
+    <td valign="top"><b>Source file name</b></td>
+    <td valign="top"><b>Target file names</b></td>
+  </tr>
+  <tr>
+    <td valign="center"><code>foo/bar/A.txt</code></td>
+    <td valign="top"><code>bar/A.txt</code></td>
+  </tr>
+</table>
+
+<p>The cutdirsmapper has no
+corresponding <code>&lt;mapper <b>type</b>&gt;</code> attribute.</p>
+
+  <table border="1" cellpadding="2" cellspacing="0">
+    <tr>
+      <td valign="top"><b>Attribute</b></td>
+      <td valign="top"><b>Description</b></td>
+      <td align="center" valign="top"><b>Required</b></td>
+    </tr>
+    <tr>
+      <td valign="top">dirs</td>
+      <td valign="top">
+        Number of directories to strip (must be a positive number).
+      </td>
+      <td align="center" valign="top">Yes</td>
+    </tr>
+  </table>
 
 </body>
 </html>

src/main/org/apache/tools/ant/types/defaults.properties

@@ -46,6 +46,7 @@ compositemapper=org.apache.tools.ant.util.CompositeMapper
 chainedmapper=org.apache.tools.ant.util.ChainedMapper
 filtermapper=org.apache.tools.ant.types.mappers.FilterMapper
 firstmatchmapper=org.apache.tools.ant.util.FirstMatchMapper
+cutdirsmapper=org.apache.tools.ant.types.mappers.CutDirsMapper
 
 #this condition is in here because it is the sole
 #condition defined in Ant1.6

src/main/org/apache/tools/ant/types/mappers/CutDirsMapper.java

@@ -0,0 +1,74 @@
+/*
+ *  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.types.mappers;
+
+import java.io.File;
+import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.util.FileNameMapper;
+
+/**
+ * A mapper that strips of the a configurable number of leading
+ * directories from a file name.
+ *
+ * <p>This mapper was inspired by a user-list thread that mentioned
+ * wget's --cut-dirs option.</p>
+ *
+ * @see http://mail-archives.apache.org/mod_mbox/ant-user/201009.mbox/%3C51772743BEA5D44A9EA5BF52AADDD6FB010E96F6@hammai008.delphi.local%3E
+ */
+public class CutDirsMapper implements FileNameMapper {
+    private int dirs = 0;
+
+    /**
+     * The number of leading directories to cut.
+     */
+    public void setDirs(int dirs) {
+        this.dirs =  dirs;
+    }
+
+    /**
+     * Empty implementation.
+     * @param ignore ignored.
+     */
+    public void setFrom(String ignore) {
+    }
+
+    /**
+     * Empty implementation.
+     * @param ignore ignored.
+     */
+    public void setTo(String ignore) {
+    }
+
+    /** {@inheritDoc}. */
+    public String[] mapFileName(final String sourceFileName) {
+        if (dirs <= 0) {
+            throw new BuildException("dirs must be set to a positive number");
+        }
+        char fileSep = File.separatorChar;
+        String fileSepCorrected =
+            sourceFileName.replace('/', fileSep).replace('\\', fileSep);
+        int nthMatch = fileSepCorrected.indexOf(fileSep);
+        for (int n = 1; nthMatch > -1 && n < dirs; n++) {
+            nthMatch = fileSepCorrected.indexOf(fileSep, nthMatch + 1);
+        }
+        if (nthMatch == -1) {
+            return null;
+        }
+        return new String[] { sourceFileName.substring(nthMatch + 1) };
+    }
+}

src/tests/antunit/types/cutdirs-test.xml

@@ -0,0 +1,56 @@
+<?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 xmlns:au="antlib:org.apache.ant.antunit"
+         name="firstmatch-test"
+         default="antunit">
+
+  <import file="../antunit-base.xml" />
+
+  <target name="setUp">
+    <mkdir dir="${input}"/>
+    <mkdir dir="${output}"/>
+  </target>
+
+  <target name="testCut" depends="setUp">
+    <mkdir dir="${input}/a/b/c"/>
+    <touch file="${input}/a/b/D"/>
+    <touch file="${input}/a/b/c/E"/>
+    <copy todir="${output}">
+      <fileset dir="${input}"/>
+      <cutdirsmapper dirs="2"/>
+    </copy>
+    <au:assertFileExists file="${output}/D"/>
+    <au:assertFileExists file="${output}/c/E"/>
+  </target>
+
+  <target name="testCutTooManyLevels" depends="setUp">
+    <mkdir dir="${input}/a/b/c"/>
+    <touch file="${input}/a/b/D"/>
+    <touch file="${input}/a/b/c/E"/>
+    <copy todir="${output}">
+      <fileset dir="${input}"/>
+      <cutdirsmapper dirs="5"/>
+    </copy>
+    <au:assertTrue>
+      <resourcecount count="0">
+        <fileset dir="${output}"/>
+      </resourcecount>
+    </au:assertTrue>
+  </target>
+
+</project>