[dvsim] Fix PEP8 error and slightly tidy code in testplan_utils.py
The PEP8 violation is comparing types for equality in this line:
elif (type(list1[key]) == type(list2[key])):
Python tends to go for duck typing, so this approach isn't
particularly Pythonic in general, but I've tried to keep the same
logic for now at least.
Since fixing this needed a bit of surgery on the code anyway, I've
used 'continue' to avoid a level of indentation and added some
comments explaining how the logic works.
Signed-off-by: Rupert Swarbrick <rswarbrick@lowrisc.org>
diff --git a/util/dvsim/testplanner/testplan_utils.py b/util/dvsim/testplanner/testplan_utils.py
index c4f8042..baa57aa 100644
--- a/util/dvsim/testplanner/testplan_utils.py
+++ b/util/dvsim/testplanner/testplan_utils.py
@@ -132,32 +132,43 @@
def merge_dicts(list1, list2, use_list1_for_defaults=True):
- '''merge 2 dicts into one
+ '''Merge 2 dicts into one
- This funciton takes 2 dicts as args list1 and list2. It recursively merges list2 into
+ This function takes 2 dicts as args list1 and list2. It recursively merges list2 into
list1 and returns list1. The recursion happens when the the value of a key in both lists
is a dict. If the values of the same key in both lists (at the same tree level) are of
dissimilar type, then there is a conflict and an error is thrown. If they are of the same
scalar type, then the third arg "use_list1_for_defaults" is used to pick the final one.
'''
- for key in list2.keys():
- if key in list1:
- if type(list1[key]) is list and type(list2[key]) is list:
- list1[key].extend(list2[key])
- elif type(list1[key]) is dict and type(list2[key]) is dict:
- list1[key] = merge_dicts(list1[key], list2[key])
- elif (type(list1[key]) == type(list2[key])):
- if not use_list1_for_defaults:
- list1[key] = list2[key]
- else:
- print("The type of value of key \"", key, "\" in list1: \"", \
- str(type(list1[key])), \
- "\" does not match the type of value in list2: \"", \
- str(type(list2[key])), \
- "\". The two lists cannot be merged.")
- sys.exit(1)
- else:
- list1[key] = list2[key]
+ for key, item2 in list2.items():
+ item1 = list1.get(key)
+ if item1 is None:
+ list1[key] = item2
+ continue
+
+ # Both dictionaries have an entry for this key. Are they both lists? If
+ # so, append.
+ if isinstance(item1, list) and isinstance(item2, list):
+ list1[key] = item1 + item2
+ continue
+
+ # Are they both dictionaries? If so, recurse.
+ if isinstance(item1, dict) and isinstance(item2, dict):
+ merge_dicts(item1, item2)
+ continue
+
+ # We treat other types as atoms. If the types of the two items are
+ # equal pick one or the other (based on use_list1_for_defaults).
+ if isinstance(item1, type(item2)) and isinstance(item2, type(item1)):
+ list1[key] = item1 if use_list1_for_defaults else item2
+ continue
+
+ # Oh no! We can't merge this.
+ print("ERROR: Cannot merge dictionaries at key {!r} because items have "
+ "conflicting types ({} in 1st; {} in 2nd)."
+ .format(type(item1), type(item2)))
+ sys.exit(1)
+
return list1
