Support IPython auto-completion for group and channel names (#259)

nptdms/tdms.py

@@ -216,6 +216,11 @@ def __getitem__(self, group_name):
         except KeyError:
             raise KeyError("There is no group named '%s' in the TDMS file" % group_name)
 
+    def _ipython_key_completions_(self):
+        """ Return possible group names for tab-completion when indexing
+        """
+        return list(self._groups.keys())
+
     def __enter__(self):
         return self
 
@@ -393,6 +398,11 @@ def __getitem__(self, channel_name):
                 "There is no channel named '%s' in group '%s' of the TDMS file" %
                 (channel_name, self.name))
 
+    def _ipython_key_completions_(self):
+        """ Return possible channel names for tab-completion when indexing
+        """
+        return list(self._channels.keys())
+
 
 class TdmsChannel(object):
     """ Represents a data channel in a TDMS file.

nptdms/test/test_tdms_file.py

@@ -1036,3 +1036,23 @@ def test_no_new_obj_list_for_first_segment():
         tdms_data = TdmsFile.read(temp_file.file)
     channel_data = tdms_data['group']['channel1']
     compare_arrays(channel_data[:], [1, 2, 3, 4, 5, 6, 7, 8])
+
+
+def test_group_name_autocompletion():
+    test_file = GeneratedFile()
+    test_file.add_segment(*basic_segment())
+    tdms_data = test_file.load()
+
+    completion_options = tdms_data._ipython_key_completions_()
+    assert "Group" in completion_options
+
+
+def test_channel_name_autocompletion():
+    test_file = GeneratedFile()
+    test_file.add_segment(*basic_segment())
+    tdms_data = test_file.load()
+
+    group = tdms_data["Group"]
+    completion_options = group._ipython_key_completions_()
+    assert "Channel1" in completion_options
+    assert "Channel2" in completion_options