view tests/test-contrib-check-code.t @ 37048:fc5e261915b9

wireproto: require POST for all HTTPv2 requests

Wire protocol version 1 transfers argument data via request
headers by default. This has historically caused problems because
servers institute limits on the length of individual HTTP headers
as well as the total size of all request headers. Mercurial servers
can advertise the maximum length of an individual header. But
there's no guarantee any intermediate HTTP agents will accept
headers up to that length.

In the existing wire protocol, server operators typically also
key off the HTTP request method to implement authentication.
For example, GET requests translate to read-only requests and
can be allowed. But read-write commands must use POST and require
authentication. This has typically worked because the only wire
protocol commands that use POST modify the repo (e.g. the
"unbundle" command).

There is an experimental feature to enable clients to transmit
argument data via POST request bodies. This is technically a
better and more robust solution. But we can't enable it by default
because of servers assuming POST means write access.

In version 2 of the wire protocol, the permissions of a request
are encoded in the URL. And with it being a new protocol in a new
URL space, we're not constrained by backwards compatibility
requirements.

This commit adopts the technically superior mechanism of using
HTTP request bodies to send argument data by requiring POST for
all commands. Strictly speaking, it may be possible to send
request bodies on GET requests. But my experience is that not all
HTTP stacks support this. POST pretty much always works. Using POST
for read-only operations does sacrifice some RESTful design
purity. But this API cares about practicality, not about being
in Roy T. Fielding's REST ivory tower.

There's a chance we may relax this restriction in the future. But
for now, I want to see how far we can get with a POST only API.

Differential Revision: https://phab.mercurial-scm.org/D2837

  $ cat > correct.py <<EOF
  > def toto(arg1, arg2):
  >     del arg2
  >     return (5 + 6, 9)
  > EOF
  $ cat > wrong.py <<EOF
  > def toto( arg1, arg2):
  >     del(arg2)
  >     return ( 5+6, 9)
  > EOF
  $ cat > quote.py <<EOF
  > # let's use quote in comments
  > (''' ( 4x5 )
  > but """\\''' and finally''',
  > """let's fool checkpatch""", '1+2',
  > '"""', 42+1, """and
  > ( 4-1 ) """, "( 1+1 )\" and ")
  > a, '\\\\\\\\', "\\\\\\" x-2", "c-1"
  > EOF
  $ cat > classstyle.py <<EOF
  > class newstyle_class(object):
  >     pass
  > 
  > class oldstyle_class:
  >     pass
  > 
  > class empty():
  >     pass
  > 
  > no_class = 1:
  >     pass
  > EOF
  $ check_code="$TESTDIR"/../contrib/check-code.py
  $ "$check_code" ./wrong.py ./correct.py ./quote.py ./classstyle.py
  ./wrong.py:1:
   > def toto( arg1, arg2):
   gratuitous whitespace in () or []
  ./wrong.py:2:
   >     del(arg2)
   Python keyword is not a function
  ./wrong.py:3:
   >     return ( 5+6, 9)
   gratuitous whitespace in () or []
   missing whitespace in expression
  ./quote.py:5:
   > '"""', 42+1, """and
   missing whitespace in expression
  ./classstyle.py:4:
   > class oldstyle_class:
   old-style class, use class foo(object)
  ./classstyle.py:7:
   > class empty():
   class foo() creates old style object, use class foo(object)
  [1]
  $ cat > python3-compat.py << EOF
  > foo <> bar
  > reduce(lambda a, b: a + b, [1, 2, 3, 4])
  > dict(key=value)
  > EOF
  $ "$check_code" python3-compat.py
  python3-compat.py:1:
   > foo <> bar
   <> operator is not available in Python 3+, use !=
  python3-compat.py:2:
   > reduce(lambda a, b: a + b, [1, 2, 3, 4])
   reduce is not available in Python 3+
  python3-compat.py:3:
   > dict(key=value)
   dict() is different in Py2 and 3 and is slower than {}
  [1]

  $ cat > foo.c <<EOF
  > void narf() {
  > 	strcpy(foo, bar);
  > 	// strcpy_s is okay, but this comment is not
  > 	strcpy_s(foo, bar);
  > }
  > EOF
  $ "$check_code" ./foo.c
  ./foo.c:2:
   > 	strcpy(foo, bar);
   don't use strcpy, use strlcpy or memcpy
  ./foo.c:3:
   > 	// strcpy_s is okay, but this comment is not
   don't use //-style comments
  [1]

  $ cat > is-op.py <<EOF
  > # is-operator comparing number or string literal
  > x = None
  > y = x is 'foo'
  > y = x is "foo"
  > y = x is 5346
  > y = x is -6
  > y = x is not 'foo'
  > y = x is not "foo"
  > y = x is not 5346
  > y = x is not -6
  > EOF

  $ "$check_code" ./is-op.py
  ./is-op.py:3:
   > y = x is 'foo'
   object comparison with literal
  ./is-op.py:4:
   > y = x is "foo"
   object comparison with literal
  ./is-op.py:5:
   > y = x is 5346
   object comparison with literal
  ./is-op.py:6:
   > y = x is -6
   object comparison with literal
  ./is-op.py:7:
   > y = x is not 'foo'
   object comparison with literal
  ./is-op.py:8:
   > y = x is not "foo"
   object comparison with literal
  ./is-op.py:9:
   > y = x is not 5346
   object comparison with literal
  ./is-op.py:10:
   > y = x is not -6
   object comparison with literal
  [1]

  $ cat > for-nolineno.py <<EOF
  > except:
  > EOF
  $ "$check_code" for-nolineno.py --nolineno
  for-nolineno.py:0:
   > except:
   naked except clause
  [1]

  $ cat > warning.t <<EOF
  >   $ function warnonly {
  >   > }
  >   $ diff -N aaa
  >   $ function onwarn {}
  > EOF
  $ "$check_code" warning.t
  $ "$check_code" --warn warning.t
  warning.t:1:
   >   $ function warnonly {
   warning: don't use 'function', use old style
  warning.t:3:
   >   $ diff -N aaa
   warning: don't use 'diff -N'
  warning.t:4:
   >   $ function onwarn {}
   warning: don't use 'function', use old style
  [1]
  $ cat > error.t <<EOF
  >   $ [ foo == bar ]
  > EOF
  $ "$check_code" error.t
  error.t:1:
   >   $ [ foo == bar ]
   [ foo == bar ] is a bashism, use [ foo = bar ] instead
  [1]
  $ rm error.t
  $ cat > raise-format.py <<EOF
  > raise SomeException, message
  > # this next line is okay
  > raise SomeException(arg1, arg2)
  > EOF
  $ "$check_code" not-existing.py raise-format.py
  Skipping*not-existing.py* (glob)
  raise-format.py:1:
   > raise SomeException, message
   don't use old-style two-argument raise, use Exception(message)
  [1]

  $ cat <<EOF > tab.t
  > 	indent
  >   > 	heredoc
  > EOF
  $ "$check_code" tab.t
  tab.t:1:
   > 	indent
   don't use tabs to indent
  [1]
  $ rm tab.t

  $ cat > rst.py <<EOF
  > """problematic rst text
  > 
  > .. note::
  >     wrong
  > """
  > 
  > '''
  > 
  > .. note::
  > 
  >     valid
  > 
  > new text
  > 
  >     .. note::
  > 
  >         also valid
  > '''
  > 
  > """mixed
  > 
  > .. note::
  > 
  >   good
  > 
  >     .. note::
  >         plus bad
  > """
  > EOF
  $ $check_code -w rst.py
  rst.py:3:
   > .. note::
   warning: add two newlines after '.. note::'
  rst.py:26:
   >     .. note::
   warning: add two newlines after '.. note::'
  [1]

  $ cat > ./map-inside-gettext.py <<EOF
  > print(_("map inside gettext %s" % v))
  > 
  > print(_("concatenating " " by " " space %s" % v))
  > print(_("concatenating " + " by " + " '+' %s" % v))
  > 
  > print(_("mapping operation in different line %s"
  >         % v))
  > 
  > print(_(
  >         "leading spaces inside of '(' %s" % v))
  > EOF
  $ "$check_code" ./map-inside-gettext.py
  ./map-inside-gettext.py:1:
   > print(_("map inside gettext %s" % v))
   don't use % inside _()
  ./map-inside-gettext.py:3:
   > print(_("concatenating " " by " " space %s" % v))
   don't use % inside _()
  ./map-inside-gettext.py:4:
   > print(_("concatenating " + " by " + " '+' %s" % v))
   don't use % inside _()
  ./map-inside-gettext.py:6:
   > print(_("mapping operation in different line %s"
   don't use % inside _()
  ./map-inside-gettext.py:9:
   > print(_(
   don't use % inside _()
  [1]

web templates

  $ mkdir -p mercurial/templates
  $ cat > mercurial/templates/example.tmpl <<EOF
  > {desc}
  > {desc|escape}
  > {desc|firstline}
  > {desc|websub}
  > EOF

  $ "$check_code" --warnings mercurial/templates/example.tmpl
  mercurial/templates/example.tmpl:2:
   > {desc|escape}
   warning: follow desc keyword with either firstline or websub
  [1]

'string join across lines with no space' detection

  $ cat > stringjoin.py <<EOF
  > foo = (' foo'
  >        'bar foo.'
  >        'bar foo:'
  >        'bar foo@'
  >        'bar foo%'
  >        'bar foo*'
  >        'bar foo+'
  >        'bar foo-'
  >        'bar')
  > EOF

'missing _() in ui message' detection

  $ cat > uigettext.py <<EOF
  > ui.status("% 10s %05d % -3.2f %*s %%"
  >           # this use '\\\\' instead of '\\', because the latter in
  >           # heredoc on shell becomes just '\'
  >           '\\\\ \n \t \0'
  >           """12345
  >           """
  >           '''.:*+-=
  >           ''' "%-6d \n 123456 .:*+-= foobar")
  > EOF

superfluous pass

  $ cat > superfluous_pass.py <<EOF
  > # correct examples
  > if foo:
  >     pass
  > else:
  >     # comment-only line means still need pass
  >     pass
  > def nothing():
  >     pass
  > class empty(object):
  >     pass
  > if whatever:
  >     passvalue(value)
  > # bad examples
  > if foo:
  >     "foo"
  >     pass
  > else: # trailing comment doesn't fool checker
  >     wat()
  >     pass
  > def nothing():
  >     "docstring means no pass"
  >     pass
  > class empty(object):
  >     """multiline
  >     docstring also
  >     means no pass"""
  >     pass
  > EOF

(Checking multiple invalid files at once examines whether caching
translation table for repquote() works as expected or not. All files
should break rules depending on result of repquote(), in this case)

  $ "$check_code" stringjoin.py uigettext.py superfluous_pass.py
  stringjoin.py:1:
   > foo = (' foo'
   string join across lines with no space
  stringjoin.py:2:
   >        'bar foo.'
   string join across lines with no space
  stringjoin.py:3:
   >        'bar foo:'
   string join across lines with no space
  stringjoin.py:4:
   >        'bar foo@'
   string join across lines with no space
  stringjoin.py:5:
   >        'bar foo%'
   string join across lines with no space
  stringjoin.py:6:
   >        'bar foo*'
   string join across lines with no space
  stringjoin.py:7:
   >        'bar foo+'
   string join across lines with no space
  stringjoin.py:8:
   >        'bar foo-'
   string join across lines with no space
  uigettext.py:1:
   > ui.status("% 10s %05d % -3.2f %*s %%"
   missing _() in ui message (use () to hide false-positives)
  superfluous_pass.py:14:
   > if foo:
   omit superfluous pass
  superfluous_pass.py:17:
   > else: # trailing comment doesn't fool checker
   omit superfluous pass
  superfluous_pass.py:20:
   > def nothing():
   omit superfluous pass
  superfluous_pass.py:23:
   > class empty(object):
   omit superfluous pass
  [1]