make error message for bad imports a little better

When an buildexception is reported in the imported xml, add the importer
xml file to the build exception


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@275610 13f79535-47bb-0310-9956-ffa450edef68

src/etc/testcases/taskdefs/import/bad.xml

@@ -0,0 +1,3 @@
+<project>
+<<<
+</project>

src/etc/testcases/taskdefs/import/import_bad_import.xml

@@ -0,0 +1,3 @@
+<project>
+  <import file="bad.xml"/>
+</project>

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

@@ -55,6 +55,7 @@
 package org.apache.tools.ant.taskdefs;
 
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.Location;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.ProjectHelper;
 import org.apache.tools.ant.Task;
@@ -179,7 +180,19 @@ public class ImportTask extends Task {
             return;
         }
 
-        helper.parse(getProject(), importedFile);
+        try {
+            helper.parse(getProject(), importedFile);
+        } catch (BuildException ex) {
+            Location exLocation = ex.getLocation();
+            if (exLocation == null) {
+                throw ex;
+            }
+            throw new BuildException(
+                "Error executing import file"
+                + System.getProperty("line.separator")
+                + exLocation.toString()
+                + " " + ex.getMessage());
+        }
     }
 
     private static String getPath(File file) {

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

@@ -54,7 +54,9 @@
 
 package org.apache.tools.ant.taskdefs;
 
+import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.BuildFileTest;
+import org.apache.tools.ant.Location;
 import org.apache.tools.ant.Project;
 
 /**
@@ -119,5 +121,27 @@ public class ImportTest extends BuildFileTest {
         expectPropertySet("within-imported", "foo", "bar");
         assertNotNull(getProject().getReference("baz"));
     }
+
+    public void testImportError() {
+        try {
+            configureProject(
+                "src/etc/testcases/taskdefs/import/import_bad_import.xml");
+        } catch (BuildException ex) {
+            Location lo = ex.getLocation();
+            assertTrue(
+                "expected location of build exception to be set",
+                (lo != null));
+            assertTrue(
+                "expected location to contain calling file",
+                lo.getFileName().indexOf("import_bad_import.xml") != -1);
+            assertTrue(
+                "expected message of ex to contain called file",
+                ex.getMessage().indexOf("bad.xml") != -1);
+            return;
+        }
+        assertTrue(
+            "Did not see build exception",
+            false);
+    }
 }