ENH: Add filename attribute to memmap.

2 files changed, 14 insertions, 0 deletions

diff --git a/numpy/core/memmap.py b/numpy/core/memmap.py
index ed888a040..b4a25cf9c 100644
--- a/numpy/core/memmap.py
+++ b/numpy/core/memmap.py
@@ -227,11 +227,13 @@ class memmap(ndarray):
         self = ndarray.__new__(subtype, shape, dtype=descr, buffer=mm,
             offset=offset, order=order)
         self._mmap = mm
+        self.filename = filename
         return self
 
     def __array_finalize__(self, obj):
         if hasattr(obj, '_mmap'):
             self._mmap = obj._mmap
+            self.filename = obj.filename
         else:
             self._mmap = None
 
diff --git a/numpy/core/tests/test_memmap.py b/numpy/core/tests/test_memmap.py
index d80724dea..fb1d7fa46 100644
--- a/numpy/core/tests/test_memmap.py
+++ b/numpy/core/tests/test_memmap.py
@@ -38,6 +38,18 @@ class TestMemmap(TestCase):
         del fp
         os.unlink(tmpname)
 
+    def test_filename(self):
+        tmpname = mktemp('','mmap')
+        fp = memmap(tmpname, dtype=self.dtype, mode='w+',
+                       shape=self.shape)
+        fp[:] = self.data[:]
+        self.assertEquals(tmpname, fp.filename)
+        b = fp[:1]
+        self.assertEquals(tmpname, b.filename)
+        del fp
+        os.unlink(tmpname)
+
+
     def test_flush(self):
         fp = memmap(self.tmpfp, dtype=self.dtype, mode='w+',
                     shape=self.shape)