From a26e586b144d8029bc7f19917a30fc817ef79d6c Mon Sep 17 00:00:00 2001
From: Philip Eisenlohr <eisenlohr@egr.msu.edu>
Date: Tue, 9 Mar 2021 19:15:15 +0000
Subject: [PATCH] More general 'delete' (accepts iterables) and backports of
 '|' and '|=' for union/add.

'|=' would work for python 3.9 without extra code, but '|' unfortunately casts 'damask.Config' (subclass of 'dict') to a 'dict'.
---
 python/damask/_config.py    | 61 ++++++++++++++++++++++---------------
 python/tests/test_Config.py | 11 ++++++-
 2 files changed, 47 insertions(+), 25 deletions(-)

diff --git a/python/damask/_config.py b/python/damask/_config.py
index edf3a5676..85f0c208c 100644
--- a/python/damask/_config.py
+++ b/python/damask/_config.py
@@ -1,5 +1,6 @@
 import copy
 from io import StringIO
+from collections.abc import Iterable
 import abc
 
 import numpy as np
@@ -44,6 +45,42 @@ class Config(dict):
     copy = __copy__
 
 
+    def __or__(self,other):
+        """
+        Update configuration with contents of other.
+
+        Parameters
+        ----------
+        other : damask.Config or dict
+            Key-value pairs that update self.
+
+        """
+        duplicate = self.copy()
+        duplicate.update(other)
+        return duplicate
+
+
+    def __ior__(self,other):
+        """Update configuration with contents of other."""
+        return self.__or__(other)
+
+
+    def delete(self,keys):
+        """
+        Remove configuration keys.
+
+        Parameters
+        ----------
+        keys : iterable or scalar
+            Label of the key(s) to remove.
+
+        """
+        duplicate = self.copy()
+        for k in keys if isinstance(keys, Iterable) and not isinstance(keys, str) else [keys]:
+            del duplicate[k]
+        return duplicate
+
+
     @classmethod
     def load(cls,fname):
         """
@@ -99,30 +136,6 @@ class Config(dict):
             fhandle.write(yaml.dump(self,Dumper=NiceDumper,**kwargs))
 
 
-    def add(self,d):
-        """
-        Add dictionary.
-
-        d : dict
-            Dictionary to append.
-        """
-        duplicate = self.copy()
-        duplicate.update(d)
-        return duplicate
-
-
-    def delete(self,key):
-        """
-        Delete item.
-
-        key : str or scalar
-            Label of the key to remove.
-        """
-        duplicate = self.copy()
-        del duplicate[key]
-        return duplicate
-
-
     @property
     @abc.abstractmethod
     def is_complete(self):
diff --git a/python/tests/test_Config.py b/python/tests/test_Config.py
index 0319fb6de..9324c28c5 100644
--- a/python/tests/test_Config.py
+++ b/python/tests/test_Config.py
@@ -23,8 +23,17 @@ class TestConfig:
             assert Config.load(f) == config
 
     def test_add_remove(self):
+        dummy = {'hello':'world','foo':'bar'}
         config = Config()
-        assert config.add({'hello':'world'}).delete('hello') == config
+        config |= dummy
+        assert config == Config() | dummy
+        config = config.delete(dummy)
+        assert config == Config()
+        assert (config |        dummy ).delete(        'hello'            ) == config | {'foo':'bar'}
+        assert (config |        dummy ).delete([       'hello',  'foo'   ]) == config
+        assert (config | Config(dummy)).delete({       'hello':1,'foo':2 }) == config
+        assert (config | Config(dummy)).delete(Config({'hello':1        })) == config | {'foo':'bar'}
+
 
     def test_repr(self,tmp_path):
         config = Config()