Issue #18960: Fix bugs with Python source code encoding in the second line.
* The first line of Python script could be executed twice when the source
encoding (not equal to 'utf-8') was specified on the second line.
* Now the source encoding declaration on the second line isn't effective if
the first line contains anything except a comment.
* As a consequence, 'python -x' works now again with files with the source
encoding declarations specified on the second file, and can be used again
to make Python batch files on Windows.
* The tokenize module now ignore the source encoding declaration on the second
line if the first line contains anything except a comment.
* IDLE now ignores the source encoding declaration on the second line if the
first line contains anything except a comment.
* 2to3 and the findnocoding.py script now ignore the source encoding
declaration on the second line if the first line contains anything except
a comment.
diff --git a/Lib/lib2to3/pgen2/tokenize.py b/Lib/lib2to3/pgen2/tokenize.py
index b7c6461..1bb931e 100644
--- a/Lib/lib2to3/pgen2/tokenize.py
+++ b/Lib/lib2to3/pgen2/tokenize.py
@@ -237,6 +237,7 @@
toks_append(tokval)
cookie_re = re.compile(r'^[ \t\f]*#.*coding[:=][ \t]*([-\w.]+)', re.ASCII)
+blank_re = re.compile(br'^[ \t\f]*(?:[#\r\n]|$)', re.ASCII)
def _get_normal_name(orig_enc):
"""Imitates get_normal_name in tokenizer.c."""
@@ -309,6 +310,8 @@
encoding = find_cookie(first)
if encoding:
return encoding, [first]
+ if not blank_re.match(first):
+ return default, [first]
second = read_or_stop()
if not second: