diff options
| -rw-r--r-- | Lib/lib2to3/Grammar.txt | 52 | ||||
| -rw-r--r-- | Lib/lib2to3/tests/test_parser.py | 31 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2020-12-14-08-23-57.bpo-36541.qdEtZv.rst | 2 |
3 files changed, 79 insertions, 6 deletions
diff --git a/Lib/lib2to3/Grammar.txt b/Lib/lib2to3/Grammar.txt index e007dc1..fa7b150 100644 --- a/Lib/lib2to3/Grammar.txt +++ b/Lib/lib2to3/Grammar.txt @@ -18,15 +18,55 @@ decorated: decorators (classdef | funcdef | async_funcdef) async_funcdef: ASYNC funcdef funcdef: 'def' NAME parameters ['->' test] ':' suite parameters: '(' [typedargslist] ')' -typedargslist: ((tfpdef ['=' test] ',')* - ('*' [tname] (',' tname ['=' test])* [',' ['**' tname [',']]] | '**' tname [',']) - | tfpdef ['=' test] (',' tfpdef ['=' test])* [',']) + +# The following definition for typedarglist is equivalent to this set of rules: +# +# arguments = argument (',' argument)* +# argument = tfpdef ['=' test] +# kwargs = '**' tname [','] +# args = '*' [tname] +# kwonly_kwargs = (',' argument)* [',' [kwargs]] +# args_kwonly_kwargs = args kwonly_kwargs | kwargs +# poskeyword_args_kwonly_kwargs = arguments [',' [args_kwonly_kwargs]] +# typedargslist_no_posonly = poskeyword_args_kwonly_kwargs | args_kwonly_kwargs +# typedarglist = arguments ',' '/' [',' [typedargslist_no_posonly]])|(typedargslist_no_posonly)" +# +# It needs to be fully expanded to allow our LL(1) parser to work on it. + +typedargslist: tfpdef ['=' test] (',' tfpdef ['=' test])* ',' '/' [ + ',' [((tfpdef ['=' test] ',')* ('*' [tname] (',' tname ['=' test])* + [',' ['**' tname [',']]] | '**' tname [',']) + | tfpdef ['=' test] (',' tfpdef ['=' test])* [','])] + ] | ((tfpdef ['=' test] ',')* ('*' [tname] (',' tname ['=' test])* + [',' ['**' tname [',']]] | '**' tname [',']) + | tfpdef ['=' test] (',' tfpdef ['=' test])* [',']) + tname: NAME [':' test] tfpdef: tname | '(' tfplist ')' tfplist: tfpdef (',' tfpdef)* [','] -varargslist: ((vfpdef ['=' test] ',')* - ('*' [vname] (',' vname ['=' test])* [',' ['**' vname [',']]] | '**' vname [',']) - | vfpdef ['=' test] (',' vfpdef ['=' test])* [',']) + +# The following definition for varargslist is equivalent to this set of rules: +# +# arguments = argument (',' argument )* +# argument = vfpdef ['=' test] +# kwargs = '**' vname [','] +# args = '*' [vname] +# kwonly_kwargs = (',' argument )* [',' [kwargs]] +# args_kwonly_kwargs = args kwonly_kwargs | kwargs +# poskeyword_args_kwonly_kwargs = arguments [',' [args_kwonly_kwargs]] +# vararglist_no_posonly = poskeyword_args_kwonly_kwargs | args_kwonly_kwargs +# varargslist = arguments ',' '/' [','[(vararglist_no_posonly)]] | (vararglist_no_posonly) +# +# It needs to be fully expanded to allow our LL(1) parser to work on it. + +varargslist: vfpdef ['=' test ](',' vfpdef ['=' test])* ',' '/' [',' [ + ((vfpdef ['=' test] ',')* ('*' [vname] (',' vname ['=' test])* + [',' ['**' vname [',']]] | '**' vname [',']) + | vfpdef ['=' test] (',' vfpdef ['=' test])* [',']) + ]] | ((vfpdef ['=' test] ',')* + ('*' [vname] (',' vname ['=' test])* [',' ['**' vname [',']]]| '**' vname [',']) + | vfpdef ['=' test] (',' vfpdef ['=' test])* [',']) + vname: NAME vfpdef: vname | '(' vfplist ')' vfplist: vfpdef (',' vfpdef)* [','] diff --git a/Lib/lib2to3/tests/test_parser.py b/Lib/lib2to3/tests/test_parser.py index ba2bb78..d5db66b 100644 --- a/Lib/lib2to3/tests/test_parser.py +++ b/Lib/lib2to3/tests/test_parser.py @@ -272,6 +272,12 @@ class TestUnpackingGeneralizations(GrammarTest): def test_dict_display_2(self): self.validate("""{**{}, 3:4, **{5:6, 7:8}}""") + def test_complex_star_expression(self): + self.validate("func(* [] or [1])") + + def test_complex_double_star_expression(self): + self.validate("func(**{1: 3} if False else {x: x for x in range(3)})") + def test_argument_unpacking_1(self): self.validate("""f(a, *b, *c, d)""") @@ -630,6 +636,7 @@ class TestLiterals(GrammarTest): class TestNamedAssignments(GrammarTest): + """Also known as the walrus operator.""" def test_named_assignment_if(self): driver.parse_string("if f := x(): pass\n") @@ -644,6 +651,30 @@ class TestNamedAssignments(GrammarTest): driver.parse_string("[(lastNum := num) == 1 for num in [1, 2, 3]]\n") +class TestPositionalOnlyArgs(GrammarTest): + + def test_one_pos_only_arg(self): + driver.parse_string("def one_pos_only_arg(a, /): pass\n") + + def test_all_markers(self): + driver.parse_string( + "def all_markers(a, b=2, /, c, d=4, *, e=5, f): pass\n") + + def test_all_with_args_and_kwargs(self): + driver.parse_string( + """def all_markers_with_args_and_kwargs( + aa, b, /, _cc, d, *args, e, f_f, **kwargs, + ): + pass\n""") + + def test_lambda_soup(self): + driver.parse_string( + "lambda a, b, /, c, d, *args, e, f, **kw: kw\n") + + def test_only_positional_or_keyword(self): + driver.parse_string("def func(a,b,/,*,g,e=3): pass\n") + + class TestPickleableException(unittest.TestCase): def test_ParseError(self): err = ParseError('msg', 2, None, (1, 'context')) diff --git a/Misc/NEWS.d/next/Library/2020-12-14-08-23-57.bpo-36541.qdEtZv.rst b/Misc/NEWS.d/next/Library/2020-12-14-08-23-57.bpo-36541.qdEtZv.rst new file mode 100644 index 0000000..5678d8c --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-12-14-08-23-57.bpo-36541.qdEtZv.rst @@ -0,0 +1,2 @@ +Fixed lib2to3.pgen2 to be able to parse PEP-570 positional only argument +syntax. |