tests: add test for Python 3 compatibility
Python 3 is inevitable. There have been incremental movements towards
converting the code base to be Python 3 compatible. Unfortunately, we
don't have any tests that look for Python 3 compatibility. This patch
changes that.
We introduce a check-py3-compat.py script whose role is to verify
Python 3 compatibility of the files passed in. We add a test that
calls this script with all .py files from the source checkout.
The script currently only verifies that absolute_import and
print_function are used. These are the low hanging fruits for Python
compatbility. Over time, we can include more checks, including
verifying we're able to load each Python file with Python 3. You
have to start somewhere.
Accepting this patch means that all new .py files must have
absolute_import and print_function (if "print" is used) to avoid
a new warning about Python 3 incompatibility. We've already
converted several files to use absolute_import and print_function
is in the same boat, so I don't think this is such a radical
proposition.
$ 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 > 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 > 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 > 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
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