[utils] Introduce merge_dicts

[youtube-dl] / youtube_dl / utils.py

diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
index 027d12785da68055477b0bd7475cfd25e4678c6b..b460393bf37106a47304dfa97dd7b1efa37117cd 100644 (file)
--- a/youtube_dl/utils.py
+++ b/youtube_dl/utils.py
@@ -2225,6 +2225,20 @@ def try_get(src, getter, expected_type=None):
                 return v
 
 
+def merge_dicts(*dicts):
+    merged = {}
+    for a_dict in dicts:
+        for k, v in a_dict.items():
+            if v is None:
+                continue
+            if (k not in merged or
+                    (isinstance(v, compat_str) and v and
+                        isinstance(merged[k], compat_str) and
+                        not merged[k])):
+                merged[k] = v
+    return merged
+
+
 def encode_compat_str(string, encoding=preferredencoding(), errors='strict'):
     return string if isinstance(string, compat_str) else compat_str(string, encoding, errors)
 
@@ -2574,8 +2588,8 @@ def _match_one(filter_part, dct):
         return op(actual_value, comparison_value)
 
     UNARY_OPERATORS = {
-        '': lambda v: v is not None,
-        '!': lambda v: v is None,
+        '': lambda v: (v is True) if isinstance(v, bool) else (v is not None),
+        '!': lambda v: (v is False) if isinstance(v, bool) else (v is None),
     }
     operator_rex = re.compile(r'''(?x)\s*
         (?P<op>%s)\s*(?P<key>[a-z_]+)