http.cookies: BaseCookie add ignore_errors kwarg to load method

Doc/library/http.cookies.rst

@@ -109,7 +109,7 @@ Cookie Objects
    The meaning for *attrs* is the same as in :meth:`output`.
 
 
-.. method:: BaseCookie.load(rawdata)
+.. method:: BaseCookie.load(rawdata, *, ignore_errors=False)
 
    If *rawdata* is a string, parse it as an ``HTTP_COOKIE`` and add the values
    found there as :class:`Morsel`\ s. If it is a dictionary, it is equivalent to::
@@ -117,6 +117,10 @@ Cookie Objects
       for k, v in rawdata.items():
           cookie[k] = v
 
+   if ignore_errors is True, skip Morsels that raise CookieError.
+
+   .. versionchanged:: 3.9
+      *ignore_errors* was added.
 
 .. _morsel-objects:
 

Lib/http/cookies.py

@@ -519,21 +519,21 @@ class BaseCookie(dict):
             result.append(value.js_output(attrs))
         return _nulljoin(result)
 
-    def load(self, rawdata):
+    def load(self, rawdata, *, ignore_errors=False):
         """Load cookies from a string (presumably HTTP_COOKIE) or
         from a dictionary.  Loading cookies from a dictionary 'd'
         is equivalent to calling:
             map(Cookie.__setitem__, d.keys(), d.values())
         """
         if isinstance(rawdata, str):
-            self.__parse_string(rawdata)
+            self.__parse_string(rawdata, ignore_errors)
         else:
             # self.update() wouldn't call our custom __setitem__
             for key, value in rawdata.items():
                 self[key] = value
         return
 
-    def __parse_string(self, str, patt=_CookiePattern):
+    def __parse_string(self, str, ignore_errors, patt=_CookiePattern):
         i = 0                 # Our starting point
         n = len(str)          # Length of string
         parsed_items = []     # Parsed (type, key, value) triples
@@ -590,8 +590,12 @@ class BaseCookie(dict):
             else:
                 assert tp == TYPE_KEYVALUE
                 rval, cval = value
-                self.__set(key, rval, cval)
-                M = self[key]
+                try:
+                    self.__set(key, rval, cval)
+                    M = self[key]
+                except CookieError:
+                    if not ignore_errors:
+                        raise
 
 
 class SimpleCookie(BaseCookie):

Lib/test/test_http_cookies.py

@@ -83,6 +83,13 @@ class CookieTests(unittest.TestCase):
         </script>
         """)
 
+        C = cookies.SimpleCookie()
+        C.load('inv/alid=test; Customer="WILE_E_COYOTE"; Version=1; Path=/acme', ignore_errors=True)
+
+        self.assertEqual(C['Customer'].value, 'WILE_E_COYOTE')
+        self.assertEqual(C['Customer']['version'], '1')
+        self.assertEqual(C['Customer']['path'], '/acme')
+
     def test_extended_encode(self):
         # Issue 9824: some browsers don't follow the standard; we now
         # encode , and ; to keep them from tripping up.

Misc/NEWS.d/next/Library/2020-03-18-12-33-11.bpo-40001.8jJvn1.rst

@@ -0,0 +1 @@
+Added `ignore_errors` keyword argument to `BaseCookie` with default value False. When True, BaseCookie load skips invalid Morsels.