Add visit and visititems methods to Group class

pyfive/high_level.py

@@ -91,7 +91,7 @@ def visit(self, func):
         return that value from the visit method.
 
         """
-        raise NotImplementedError
+        return self.visititems(lambda name, obj: func(name))
 
     def visititems(self, func):
         """
@@ -105,7 +105,19 @@ def visititems(self, func):
         return that value from the visit method.
 
         """
-        raise NotImplementedError
+        root_name_length = len(self.name)
+        if not self.name.endswith('/'):
+            root_name_length += 1
+        queue = deque(self.values())
+        while queue:
+            obj = queue.popleft()
+            name = obj.name[root_name_length:]
+            ret = func(name, obj)
+            if ret is not None:
+                return ret
+            if isinstance(obj, Group):
+                queue.extend(obj.values())
+        return None
 
     @property
     def attrs(self):
@@ -167,15 +179,10 @@ def __init__(self, filename):
 
     def _get_object_by_address(self, obj_addr):
         """ Return the object pointed to by a given address. """
-        # breadth first search of the file hierarchy for the given address
-        queue = deque([self])
-        while queue:
-            obj = queue.popleft()
-            if obj._dataobjects.offset == obj_addr:
-                return obj
-            if isinstance(obj, Group):
-                queue.extend(child for child in obj.values())
-        return None
+        if self._dataobjects.offset == obj_addr:
+            return self
+        return self.visititems(
+            lambda x, y: y if y._dataobjects.offset == obj_addr else None)
 
     def close(self):
         """ Close the file. """

tests/test_visit.py

@@ -0,0 +1,44 @@
+""" Test visit and visititems methods. """
+from __future__ import print_function
+
+import os
+
+import pyfive
+
+DIRNAME = os.path.dirname(__file__)
+GROUPS_HDF5_FILE = os.path.join(DIRNAME, 'groups.hdf5')
+
+
+def test_visit_method():
+    with pyfive.File(GROUPS_HDF5_FILE) as hfile:
+
+        assert hfile.visit(lambda x: print(x)) is None
+
+        name = 'group2/subgroup1'
+        assert hfile.visit(lambda x: x if x == name else None) == name
+
+        name = '/group2/subgroup1'  # starts with /, not found
+        assert hfile.visit(lambda x: x if x == name else None) is None
+
+        group2 = hfile['group2']
+
+        name = 'subgroup1'
+        assert group2.visit(lambda x: x if x == name else None) == name
+
+        name = 'group2/subgroup1'  # rooted at group2
+        assert group2.visit(lambda x: x if x == name else None) is None
+
+
+def test_visititems_method():
+    with pyfive.File(GROUPS_HDF5_FILE) as hfile:
+
+        assert hfile.visititems(lambda x, y: print(x, y.name)) is None
+
+        name = 'group2/subgroup1'
+        ret = hfile.visititems(lambda x, y: x if x == name else None)
+        assert ret == name
+
+        name = '/group2/subgroup1'  # starts with /, not found
+        assert hfile.visititems(lambda x, y: x if x == name else None) is None
+        ret = hfile.visititems(lambda x, y: y if y.name == name else None)
+        assert ret.name == name