From e9c65dee7382f5f2220074d1ee20f41fec48c7e0 Mon Sep 17 00:00:00 2001
From: Martin Diehl <mail@martin-diehl.net>
Date: Wed, 31 Mar 2021 10:59:21 +0200
Subject: [PATCH] documenting and testing

---
 python/damask/util.py     | 52 ++++++++++++++++++++++++++-------------
 python/tests/test_util.py | 22 +++++++++++++++++
 2 files changed, 57 insertions(+), 17 deletions(-)

diff --git a/python/damask/util.py b/python/damask/util.py
index 735db39a0..b79df193a 100644
--- a/python/damask/util.py
+++ b/python/damask/util.py
@@ -399,34 +399,52 @@ def DREAM3D_cell_data_group(fname):
 
     return cell_data_group
 
-def dict_strip(a_dict):
+
+def dict_strip(d):
+    """
+    Remove recursively empty dictionaries.
+
+    Parameters
+    ----------
+    d : dict
+        dictionary.
+
+    """
     # https://stackoverflow.com/questions/48151953
-    new_dict = {}
-    for k, v in a_dict.items():
+    new = {}
+    for k,v in d.items():
         if isinstance(v, dict):
             v = dict_strip(v)
         if not isinstance(v,dict) or v != {}:
-            new_dict[k] = v
-    return new_dict
+            new[k] = v
+    return new
 
 
-def dict_compress(a_dict):
-    # https://stackoverflow.com/questions/48151953
-    if isinstance(a_dict,dict) and len(a_dict) == 1:
-        key = list(a_dict.keys())[0]
-        entry = a_dict[key]
+def dict_compress(d):
+    """
+    Remove recursively dictionaries with one entry.
+
+    Parameters
+    ----------
+    d : dict
+        dictionary.
+
+    """
+    if isinstance(d,dict) and len(d) == 1:
+        key = list(d.keys())[0]
+        entry = d[key]
         if isinstance(entry,dict):
-            new_dict = dict_compress(entry.copy())
+            new = dict_compress(entry.copy())
         else:
-            new_dict = entry
+            new = entry
     else:
-        new_dict = {}
-        for k, v in a_dict.items():
+        new = {}
+        for k,v in d.items():
             if isinstance(v, dict):
                 v = dict_compress(v)
-            if not isinstance(v,dict) or v != {}:
-                new_dict[k] = v
-    return new_dict
+            if not isinstance(v,dict) or v == {}:
+                new[k] = v
+    return new
 
 
 
diff --git a/python/tests/test_util.py b/python/tests/test_util.py
index b96908a9a..500e7d733 100644
--- a/python/tests/test_util.py
+++ b/python/tests/test_util.py
@@ -136,3 +136,25 @@ class TestUtil:
         else:
             with pytest.raises(ValueError):
                 util.DREAM3D_cell_data_group(tmp_path/'cell_data_group.dream3d')
+
+
+    @pytest.mark.parametrize('full,reduced',[({},                           {}),
+                                             ({'A':{}},                     {}),
+                                             ({'A':{'B':{}}},               {}),
+                                             ({'A':{'B':'C'}},)*2,
+                                             ({'A':{'B':{},'C':'D'}},       {'A':{'C':'D'}})])
+    def test_strip(self,full,reduced):
+        assert util.dict_strip(full) == reduced
+
+
+    @pytest.mark.parametrize('full,reduced',[({},                           {}),
+                                             ({'A':{}},                     {}),
+                                             ({'A':'F'},                    'F'),
+                                             ({'A':{'B':{}}},               {}),
+                                             ({'A':{'B':'C'}},              'C'),
+                                             ({'A':1,'B':2},)*2,
+                                             ({'A':{'B':'C','D':'E'}},      {'B':'C','D':'E'}),
+                                             ({'B':'C','D':'E'},)*2,
+                                             ({'A':{'B':{},'C':'D'}},       {'B':{},'C':'D'})])
+    def test_compress(self,full,reduced):
+        assert util.dict_compress(full) == reduced