diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/email/utils.py | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/Lib/email/utils.py b/Lib/email/utils.py index 93a625c..b3b42bb 100644 --- a/Lib/email/utils.py +++ b/Lib/email/utils.py @@ -54,10 +54,16 @@ TICK = "'" specialsre = re.compile(r'[][\\()<>@,:;".]') escapesre = re.compile(r'[\\"]') -# How to figure out if we are processing strings that come from a byte -# source with undecodable characters. -_has_surrogates = re.compile( - '([^\ud800-\udbff]|\A)[\udc00-\udfff]([^\udc00-\udfff]|\Z)').search +def _has_surrogates(s): + """Return True if s contains surrogate-escaped binary data.""" + # This check is based on the fact that unless there are surrogates, utf8 + # (Python's default encoding) can encode any string. This is the fastest + # way to check for surrogates, see issue 11454 for timings. + try: + s.encode() + return False + except UnicodeEncodeError: + return True # How to deal with a string containing bytes before handing it to the # application through the 'normal' interface. |