Merge branch 'main' into asyncio-subprocess-cancellation

Author: kumaraditya303

Doc/library/code.rst

@@ -29,7 +29,7 @@ build applications which provide an interactive interpreter prompt.
    module.
 
 
-.. class:: InteractiveConsole(locals=None, filename="<console>", local_exit=False)
+.. class:: InteractiveConsole(locals=None, filename="<console>", *, local_exit=False)
 
    Closely emulate the behavior of the interactive Python interpreter. This class
    builds on :class:`InteractiveInterpreter` and adds prompting using the familiar

Lib/email/message.py

@@ -74,19 +74,25 @@ def _parseparam(s):
     # RDM This might be a Header, so for now stringify it.
     s = ';' + str(s)
     plist = []
-    while s[:1] == ';':
-        s = s[1:]
-        end = s.find(';')
-        while end > 0 and (s.count('"', 0, end) - s.count('\\"', 0, end)) % 2:
-            end = s.find(';', end + 1)
+    start = 0
+    while s.find(';', start) == start:
+        start += 1
+        end = s.find(';', start)
+        ind, diff = start, 0
+        while end > 0:
+            diff += s.count('"', ind, end) - s.count('\\"', ind, end)
+            if diff % 2 == 0:
+                break
+            end, ind = ind, s.find(';', end + 1)
         if end < 0:
             end = len(s)
-        f = s[:end]
-        if '=' in f:
-            i = f.index('=')
-            f = f[:i].strip().lower() + '=' + f[i+1:].strip()
+        i = s.find('=', start, end)
+        if i == -1:
+            f = s[start:end]
+        else:
+            f = s[start:i].rstrip().lower() + '=' + s[i+1:end].lstrip()
         plist.append(f.strip())
-        s = s[end:]
+        start = end
     return plist
 
 

Lib/http/client.py

@@ -1391,8 +1391,7 @@ def getresponse(self):
         """Get the response from the server.
 
         If the HTTPConnection is in the correct state, returns an
-        instance of HTTPResponse or of whatever object is returned by
-        the response_class variable.
+        instance of HTTPResponse.
 
         If a request has not been sent or if a previous response has
         not be handled, ResponseNotReady is raised.  If the HTTP

Lib/ntpath.py

@@ -400,17 +400,23 @@ def expanduser(path):
 # XXX With COMMAND.COM you can use any characters in a variable name,
 # XXX except '^|<>='.
 
+_varpattern = r"'[^']*'?|%(%|[^%]*%?)|\$(\$|[-\w]+|\{[^}]*\}?)"
+_varsub = None
+_varsubb = None
+
 def expandvars(path):
     """Expand shell variables of the forms $var, ${var} and %var%.
 
     Unknown variables are left unchanged."""
     path = os.fspath(path)
+    global _varsub, _varsubb
     if isinstance(path, bytes):
         if b'$' not in path and b'%' not in path:
             return path
-        import string
-        varchars = bytes(string.ascii_letters + string.digits + '_-', 'ascii')
-        quote = b'\''
+        if not _varsubb:
+            import re
+            _varsubb = re.compile(_varpattern.encode(), re.ASCII).sub
+        sub = _varsubb
         percent = b'%'
         brace = b'{'
         rbrace = b'}'
@@ -419,94 +425,44 @@ def expandvars(path):
     else:
         if '$' not in path and '%' not in path:
             return path
-        import string
-        varchars = string.ascii_letters + string.digits + '_-'
-        quote = '\''
+        if not _varsub:
+            import re
+            _varsub = re.compile(_varpattern, re.ASCII).sub
+        sub = _varsub
         percent = '%'
         brace = '{'
         rbrace = '}'
         dollar = '$'
         environ = os.environ
-    res = path[:0]
-    index = 0
-    pathlen = len(path)
-    while index < pathlen:
-        c = path[index:index+1]
-        if c == quote:   # no expansion within single quotes
-            path = path[index + 1:]
-            pathlen = len(path)
-            try:
-                index = path.index(c)
-                res += c + path[:index + 1]
-            except ValueError:
-                res += c + path
-                index = pathlen - 1
-        elif c == percent:  # variable or '%'
-            if path[index + 1:index + 2] == percent:
-                res += c
-                index += 1
-            else:
-                path = path[index+1:]
-                pathlen = len(path)
-                try:
-                    index = path.index(percent)
-                except ValueError:
-                    res += percent + path
-                    index = pathlen - 1
-                else:
-                    var = path[:index]
-                    try:
-                        if environ is None:
-                            value = os.fsencode(os.environ[os.fsdecode(var)])
-                        else:
-                            value = environ[var]
-                    except KeyError:
-                        value = percent + var + percent
-                    res += value
-        elif c == dollar:  # variable or '$$'
-            if path[index + 1:index + 2] == dollar:
-                res += c
-                index += 1
-            elif path[index + 1:index + 2] == brace:
-                path = path[index+2:]
-                pathlen = len(path)
-                try:
-                    index = path.index(rbrace)
-                except ValueError:
-                    res += dollar + brace + path
-                    index = pathlen - 1
-                else:
-                    var = path[:index]
-                    try:
-                        if environ is None:
-                            value = os.fsencode(os.environ[os.fsdecode(var)])
-                        else:
-                            value = environ[var]
-                    except KeyError:
-                        value = dollar + brace + var + rbrace
-                    res += value
-            else:
-                var = path[:0]
-                index += 1
-                c = path[index:index + 1]
-                while c and c in varchars:
-                    var += c
-                    index += 1
-                    c = path[index:index + 1]
-                try:
-                    if environ is None:
-                        value = os.fsencode(os.environ[os.fsdecode(var)])
-                    else:
-                        value = environ[var]
-                except KeyError:
-                    value = dollar + var
-                res += value
-                if c:
-                    index -= 1
+
+    def repl(m):
+        lastindex = m.lastindex
+        if lastindex is None:
+            return m[0]
+        name = m[lastindex]
+        if lastindex == 1:
+            if name == percent:
+                return name
+            if not name.endswith(percent):
+                return m[0]
+            name = name[:-1]
         else:
-            res += c
-        index += 1
-    return res
+            if name == dollar:
+                return name
+            if name.startswith(brace):
+                if not name.endswith(rbrace):
+                    return m[0]
+                name = name[1:-1]
+
+        try:
+            if environ is None:
+                return os.fsencode(os.environ[os.fsdecode(name)])
+            else:
+                return environ[name]
+        except KeyError:
+            return m[0]
+
+    return sub(repl, path)
 
 
 # Normalize a path, e.g. A//B, A/./B and A/foo/../B all become A\B.

Lib/posixpath.py

@@ -285,56 +285,53 @@ def expanduser(path):
 # This expands the forms $variable and ${variable} only.
 # Non-existent variables are left unchanged.
 
-_varprog = None
-_varprogb = None
+_varpattern = r'\$(\w+|\{[^}]*\}?)'
+_varsub = None
+_varsubb = None
 
 def expandvars(path):
     """Expand shell variables of form $var and ${var}.  Unknown variables
     are left unchanged."""
     path = os.fspath(path)
-    global _varprog, _varprogb
+    global _varsub, _varsubb
     if isinstance(path, bytes):
         if b'$' not in path:
             return path
-        if not _varprogb:
+        if not _varsubb:
             import re
-            _varprogb = re.compile(br'\$(\w+|\{[^}]*\})', re.ASCII)
-        search = _varprogb.search
+            _varsubb = re.compile(_varpattern.encode(), re.ASCII).sub
+        sub = _varsubb
         start = b'{'
         end = b'}'
         environ = getattr(os, 'environb', None)
     else:
         if '$' not in path:
             return path
-        if not _varprog:
+        if not _varsub:
             import re
-            _varprog = re.compile(r'\$(\w+|\{[^}]*\})', re.ASCII)
-        search = _varprog.search
+            _varsub = re.compile(_varpattern, re.ASCII).sub
+        sub = _varsub
         start = '{'
         end = '}'
         environ = os.environ
-    i = 0
-    while True:
-        m = search(path, i)
-        if not m:
-            break
-        i, j = m.span(0)
-        name = m.group(1)
-        if name.startswith(start) and name.endswith(end):
+
+    def repl(m):
+        name = m[1]
+        if name.startswith(start):
+            if not name.endswith(end):
+                return m[0]
             name = name[1:-1]
         try:
             if environ is None:
                 value = os.fsencode(os.environ[os.fsdecode(name)])
             else:
                 value = environ[name]
         except KeyError:
-            i = j
+            return m[0]
         else:
-            tail = path[j:]
-            path = path[:i] + value
-            i = len(path)
-            path += tail
-    return path
+            return value
+
+    return sub(repl, path)
 
 
 # Normalize a path, e.g. A//B, A/./B and A/foo/../B all become A/B.

Lib/test/test_email/test_email.py

@@ -481,6 +481,27 @@ def test_get_param_with_quotes(self):
             "Content-Type: foo; bar*0=\"baz\\\"foobar\"; bar*1=\"\\\"baz\"")
         self.assertEqual(msg.get_param('bar'), 'baz"foobar"baz')
 
+    def test_get_param_linear_complexity(self):
+        # Ensure that email.message._parseparam() is fast.
+        # See https://github.com/python/cpython/issues/136063.
+        N = 100_000
+        for s, r in [
+            ("", ""),
+            ("foo=bar", "foo=bar"),
+            (" FOO = bar    ", "foo=bar"),
+        ]:
+            with self.subTest(s=s, r=r, N=N):
+                src = f'{s};' * (N - 1) + s
+                res = email.message._parseparam(src)
+                self.assertEqual(len(res), N)
+                self.assertEqual(len(set(res)), 1)
+                self.assertEqual(res[0], r)
+
+        # This will be considered as a single parameter.
+        malformed = 's="' + ';' * (N - 1)
+        res = email.message._parseparam(malformed)
+        self.assertEqual(res, [malformed])
+
     def test_field_containment(self):
         msg = email.message_from_string('Header: exists')
         self.assertIn('header', msg)

Lib/test/test_genericpath.py

@@ -9,9 +9,9 @@
 import sys
 import unittest
 import warnings
-from test.support import (
-    is_apple, os_helper, warnings_helper
-)
+from test import support
+from test.support import os_helper
+from test.support import warnings_helper
 from test.support.script_helper import assert_python_ok
 from test.support.os_helper import FakePath
 
@@ -462,6 +462,19 @@ def check(value, expected):
                   os.fsencode('$bar%s bar' % nonascii))
             check(b'$spam}bar', os.fsencode('%s}bar' % nonascii))
 
+    @support.requires_resource('cpu')
+    def test_expandvars_large(self):
+        expandvars = self.pathmodule.expandvars
+        with os_helper.EnvironmentVarGuard() as env:
+            env.clear()
+            env["A"] = "B"
+            n = 100_000
+            self.assertEqual(expandvars('$A'*n), 'B'*n)
+            self.assertEqual(expandvars('${A}'*n), 'B'*n)
+            self.assertEqual(expandvars('$A!'*n), 'B!'*n)
+            self.assertEqual(expandvars('${A}A'*n), 'BA'*n)
+            self.assertEqual(expandvars('${'*10*n), '${'*10*n)
+
     def test_abspath(self):
         self.assertIn("foo", self.pathmodule.abspath("foo"))
         with warnings.catch_warnings():
@@ -519,7 +532,7 @@ def test_nonascii_abspath(self):
             # directory (when the bytes name is used).
             and sys.platform not in {
                 "win32", "emscripten", "wasi"
-            } and not is_apple
+            } and not support.is_apple
         ):
             name = os_helper.TESTFN_UNDECODABLE
         elif os_helper.TESTFN_NONASCII: