Don't unzip the sources which were bundled originally. Guix strips them from
the source and uses pre-build packages.

Taken from https://anonscm.debian.org/viewvc/pkg-java/trunk/libxerces2-java/debian/patches/02_build_dont_unzip.patch?revision=14507

Index: b/build.xml
===================================================================
--- a/build.xml
+++ b/build.xml
@@ -247,7 +247,7 @@
     <copy file="${src.dir}/org/apache/xerces/impl/xpath/regex/message.properties"
       tofile="${build.src}/org/apache/xerces/impl/xpath/regex/message_en.properties"/>
 
-    <!-- now deal with API's:  -->
+    <!-- not needed for Debian
     <unzip src="${src.apis.zip}" dest="${build.src}">
         <patternset
             includes="org/xml/sax/** 
@@ -270,6 +270,7 @@
                 org/w3c/dom/xpath/**"
         />
     </unzip>
+    -->
     
     <!-- substitute tokens as needed -->
     <replace file="${build.dir}/src/org/apache/xerces/impl/Version.java" 
@@ -1232,7 +1233,7 @@
     <replace file="${build.dir}/src/org/apache/xerces/parsers/AbstractSAXParser.java"
              token="return (fConfiguration instanceof XML11Configurable);" value="return false;"/>
  
-    <!-- now deal with API's:  -->
+    <!-- not needed for Debian
     <unzip src="${src.apis.zip}" dest="${build.src}">
         <patternset
             includes="org/xml/sax/** 
@@ -1255,7 +1256,7 @@
                 org/w3c/dom/xpath/**"
         />
     </unzip>
-
+    -->
 
     <!-- substitute tokens as needed -->
     <replace file="${build.dir}/src/org/apache/xerces/impl/Version.java" 
0990cc4a3308ae269c74aee62'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=053677ba3bad3520990cc4a3308ae269c74aee62'>root</a>/<a href='/guix/log/CODE-OF-CONDUCT?id=053677ba3bad3520990cc4a3308ae269c74aee62'>CODE-OF-CONDUCT</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/CODE-OF-CONDUCT?id=053677ba3bad3520990cc4a3308ae269c74aee62&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2018-05-29 18:29:36 +0200'>2018-05-29</span></td><td><a href='/guix/commit/CODE-OF-CONDUCT?id=a076f19908d06b6df49f1c25c40de8838213cd71'>CODE-OF-CONDUCT: Switch to version 1.4 of the Contributor Covenant.</a><span class='msg-avail'>...<span class='msg-tooltip'>See the discussion at
&lt;https://lists.gnu.org/archive/html/guix-devel/2018-05/msg00146.html&gt;.

* CODE-OF-CONDUCT: Adapt from version 1.4 of the Contributor Covenant.
</span></span></td><td>Ludovic Courtès</td></tr>
ommits"): Adjust
accordingly.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-05-25 00:00:28 +0200'>2020-05-25</span></td><td><a href='/guix/commit/tests/git.scm?id=c098c11be8eb9e0c12be42640721e3cb21c37628'>git: Add 'commit-relation'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/git.scm (commit-relation): New procedure.
* tests/git.scm ("commit-relation"): New test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-12-27 13:52:49 +0100'>2019-12-27</span></td><td><a href='/guix/commit/tests/git.scm?id=785af04a7574867dc940c791daa938a2432d0450'>git: 'commit-difference' takes a list of excluded commits.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/git.scm (commit-closure): Add 'visited' optional parameter.
(commit-difference): Add 'excluded' optional parameter; pass second
argument to 'commit-closure'.
* tests/git.scm ("commit-difference, excluded commits"): New test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-09-23 10:38:43 +0200'>2019-09-23</span></td><td><a href='/guix/commit/tests/git.scm?id=873f6f1334ab06a69e768a8aea0054404237542f'>git: Add 'commit-difference'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/git.scm (commit-closure, commit-difference): New procedures.
* guix/tests/git.scm, tests/git.scm: New files.
* Makefile.am (dist_noinst_DATA): Add guix/tests/git.scm.
(SCM_TESTS): Add tests/git.scm.
</span></span></td><td>Ludovic Courtès</td></tr>