Restore Task inheritance to Exit/<fail>.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@276428 13f79535-47bb-0310-9956-ffa450edef68

docs/manual/CoreTasks/fail.html

@@ -41,10 +41,10 @@ or character data nested into the element.</p>
 <h3>Parameters specified as nested elements</h3>
 
 <p>As an alternative to the <i>if</i>/<i>unless</i> attributes,
-  conditional failure can be achieved using a single nested condition.
-  For a complete list of core conditions, as well as information
-  about custom conditions, see <a href="conditions.html">here</a>.<br />
-  <b>Since Ant 1.6.2</b>
+  conditional failure can be achieved using a single nested
+  &lt;condition&gt; element, which should contain exactly one
+  core or custom condition.  For information about conditions, see
+  <a href="conditions.html">here</a>.<br /><b>Since Ant 1.6.2</b>
 </p>
 
 <h3>Examples</h3>
@@ -79,12 +79,15 @@ BUILD FAILED
 build.xml:2: unless=thisdoesnotexist
 </pre>
 
-A simple example using conditions to achieve the same effect:
+Using a condition to achieve the same effect:
+
 <pre>
   &lt;fail&gt;
-     &lt;not&gt;
-       &lt;isset property=&quot;thisdoesnotexist&quot;/&gt;
-     &lt;/not&gt;
+     &lt;condition&gt;
+       &lt;not&gt;
+         &lt;isset property=&quot;thisdoesnotexist&quot;/&gt;
+       &lt;/not&gt;
+     &lt;/condition&gt;
    &lt;/fail&gt;
 </pre>
 

src/etc/testcases/taskdefs/fail.xml

@@ -28,54 +28,87 @@
   
   <target name="testNested1" description="should fail with default message">
     <fail>
-      <and />
+      <condition>
+          <and />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested2" description="should pass">
     <fail>
-      <or />
+      <condition>
+          <or />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested3" description="should fail">
     <fail message="testNested3">
-      <and />
+      <condition>
+          <and />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested4a" description="should error">
     <fail if="if">
-      <and />
+      <condition>
+          <and />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested4b" description="should error">
     <fail unless="unless">
-      <and />
+      <condition>
+          <and />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested4c" description="should error">
     <fail if="if" unless="unless">
-      <and />
+      <condition>
+          <and />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested5" description="should error">
     <fail>
-      <and />
-      <or />
+      <condition>
+          <or />
+      </condition>
+      <condition>
+          <and />
+      </condition>
     </fail>
   </target>
 
   <target name="testNested6" description="should fail with message">
     <fail>
-      <and />
+      <condition>
+          <and />
+      </condition>
 testNested6
 testNested6
 testNested6
     </fail>
   </target>
 
+  <target name="testNested7a" description="should error">
+    <fail>
+      <condition />
+    </fail>
+  </target>
+
+  <target name="testNested7b" description="should error">
+    <fail>
+      <condition>
+          <and />
+          <and />
+      </condition>
+    </fail>
+  </target>
+
 </project>

src/main/org/apache/tools/ant/taskdefs/Exit.java

@@ -17,6 +17,8 @@
 
 package org.apache.tools.ant.taskdefs;
 
+import java.util.Vector;
+import org.apache.tools.ant.Task;
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.taskdefs.condition.Condition;
 import org.apache.tools.ant.taskdefs.condition.ConditionBase;
@@ -42,9 +44,21 @@ import org.apache.tools.ant.taskdefs.condition.ConditionBase;
  *
  * @ant.task name="fail" category="control"
  */
-public class Exit extends ConditionBase {
+public class Exit extends Task {
+
+    private class NestedCondition extends ConditionBase implements Condition {
+        public boolean eval() {
+            if (countConditions() != 1) {
+                throw new BuildException(
+                    "A single nested condition is required.");
+            }
+            return ((Condition)(getConditions().nextElement())).eval();
+        }
+    }
+
     private String message;
     private String ifCondition, unlessCondition;
+    private NestedCondition nestedCondition;
 
     /**
      * A message giving further information on why the build exited.
@@ -128,6 +142,19 @@ public class Exit extends ConditionBase {
         message += getProject().replaceProperties(msg);
     }
 
+    /**
+     * Add a condition element.
+     * @return <CODE>ConditionBase</CODE>.
+     * @since Ant 1.6.2
+     */
+    public ConditionBase createCondition() {
+        if (nestedCondition != null) {
+            throw new BuildException("Only one nested condition is allowed.");
+        }
+        nestedCondition = new NestedCondition();
+        return nestedCondition;
+    }
+
     /**
      * test the if condition
      * @return true if there is no if condition, or the named property exists
@@ -156,21 +183,22 @@ public class Exit extends ConditionBase {
      * @return true if there is none, or it evaluates to true
      */
     private boolean testNestedCondition() {
-        if (ifCondition != null || unlessCondition != null) {
-            throw new BuildException("Nested conditions "
-              + "not permitted in conjunction with if/unless attributes");
-        }
+        boolean result = nestedConditionPresent();
 
-        int count = countConditions();
-        if (count > 1) {
-            throw new BuildException("Too many conditions:  " + count);
+        if (result && ifCondition != null || unlessCondition != null) {
+            throw new BuildException("Nested conditions "
+                + "not permitted in conjunction with if/unless attributes");
         }
 
-        return (count == 0) ? true
-            : (((Condition)(getConditions().nextElement())).eval());
+        return result && nestedCondition.eval();
     }
 
+    /**
+     * test whether there is a nested condition.
+     * @return <CODE>boolean</CODE>.
+     */
     private boolean nestedConditionPresent() {
-        return (countConditions() > 0);
+        return (nestedCondition != null);
     }
+
 }

src/testcases/org/apache/tools/ant/taskdefs/FailTest.java

@@ -138,7 +138,7 @@ public class FailTest extends BuildFileTest {
     public void testNested5() {
         expectSpecificBuildException("testNested5",
             "it is required to fail :-)",
-            "Too many conditions:  2");
+            "Only one nested condition is allowed.");
     }
 
     public void testNested6() {
@@ -147,4 +147,17 @@ public class FailTest extends BuildFileTest {
             "testNested6\ntestNested6\ntestNested6");
     }
 
- }
+    public void testNested7() {
+        String specificMessage = "A single nested condition is required.";
+
+        char[] c = {'a', 'b'};
+        StringBuffer target = new StringBuffer("testNested7x");
+
+        for (int i = 0; i < c.length; i++) {
+            target.setCharAt(target.length() - 1, c[i]);
+            expectSpecificBuildException(target.toString(),
+                "it is required to fail :-)", specificMessage);
+        }
+    }
+
+}