From e4138014228bd441bc30a497a8395f7753e691e4 Mon Sep 17 00:00:00 2001
From: Matthew Jason Benson <mbenson@apache.org>
Date: Tue, 24 Jul 2007 16:32:09 +0000
Subject: [PATCH] Regression: Path subclasses that overrode list() stopped
 working in resourceCollection contexts in Ant 1.7.0. Bugzilla 42967.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@559096 13f79535-47bb-0310-9956-ffa450edef68
---
 WHATSNEW                                      |  3 ++
 src/main/org/apache/tools/ant/types/Path.java | 28 +++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/WHATSNEW b/WHATSNEW
index 53b1ece94..d08a03382 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -124,6 +124,9 @@ Fixed bugs:
 * Modified selector doesn't update the cache if only one file has changed.
   Bugzilla 42802.
 
+* Regression: Path subclasses that overrode list() stopped working in
+  resourceCollection contexts in Ant 1.7.0. Bugzilla 42967.
+
 Other changes:
 --------------
 * <script> now has basic support for JavaFX scripts
diff --git a/src/main/org/apache/tools/ant/types/Path.java b/src/main/org/apache/tools/ant/types/Path.java
index 6a5201ca2..1a97eee58 100644
--- a/src/main/org/apache/tools/ant/types/Path.java
+++ b/src/main/org/apache/tools/ant/types/Path.java
@@ -19,6 +19,7 @@
 package org.apache.tools.ant.types;
 
 import java.io.File;
+import java.lang.reflect.Method;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.Locale;
@@ -141,6 +142,8 @@ public class Path extends DataType implements Cloneable, ResourceCollection {
 
     }
 
+    private final boolean preserveBC = delegateIteratorToList();
+
     private Union union = null;
 
     /**
@@ -684,6 +687,9 @@ public class Path extends DataType implements Cloneable, ResourceCollection {
             return ((Path) getCheckedRef()).iterator();
         }
         dieOnCircularReference();
+        if (preserveBC) {
+            return new FileResourceIterator(null, list());
+        }
         return union == null ? EMPTY_ITERATOR
             : assertFilesystemOnly(union).iterator();
     }
@@ -714,4 +720,26 @@ public class Path extends DataType implements Cloneable, ResourceCollection {
         }
         return rc;
     }
+
+    /**
+     * Helps determine whether to preserve BC by calling <code>list()</code> on subclasses.
+     * The default behavior of this method is to return <code>true</code> for any subclass
+     * that implements <code>list()</code>; this can, of course, be avoided by overriding
+     * this method to return <code>false</code>. It is not expected that the result of this
+     * method should change over time; thus it is called a single time during instance
+     * initialization.
+     * @return <code>true</code> if <code>iterator()</code> should delegate to <code>list()</code>.
+     */
+    protected boolean delegateIteratorToList() {
+        if (getClass().equals(Path.class)) {
+            return false;
+        }
+        try {
+            Method listMethod = getClass().getMethod("list", (Class[]) null);
+            return !listMethod.getDeclaringClass().equals(Path.class);
+        } catch (Exception e) {
+            //shouldn't happen, but
+            return false;
+        }
+    }
 }