From f9e59d060fbdad57f8d927cf51eade0d46b47e12 Mon Sep 17 00:00:00 2001 From: Lancelot SIX Date: Mon, 7 Jun 2021 23:14:55 +0100 Subject: Use is/is not to check for None in python code. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit While reviewing a patch sent to the mailing list, I noticed there are few places where python code checks if a variable is 'None' or not by using the comparison operators '==' and '!='. PEP8[1], which is used as coding standard in GDB coding standards, recommends using 'is' / 'is not' when comparing to a singleton such as 'None'. This patch proposes to change the instances of '== None' by 'is None' and '!= None' by 'is not None'. [1] https://www.python.org/dev/peps/pep-0008/ gdb/doc/ChangeLog: * python.texi (Writing a Pretty-Printer): Use 'is None' instead of '== None'. gdb/ChangeLog: * python/lib/gdb/FrameDecorator.py (FrameDecorator): Use 'is None' instead of '== None'. (FrameVars): Use 'is not None' instead of '!= None'. * python/lib/gdb/command/frame_filters.py (SetFrameFilterPriority): Use 'is None' instead of '== None' and 'is not None' instead of '!= None'. gdb/testsuite/ChangeLog: * gdb.base/premature-dummy-frame-removal.py (TestUnwinder): Use 'is None' instead of '== None' and 'is not None' instead of '!= None'. * gdb.python/py-frame-args.py (lookup_function): Same. * gdb.python/py-framefilter-invalidarg.py (Reverse_Function): Same. * gdb.python/py-framefilter.py (Reverse_Function): Same. * gdb.python/py-nested-maps.py (lookup_function): Same. * gdb.python/py-objfile-script-gdb.py (lookup_function): Same. * gdb.python/py-prettyprint.py (lookup_function): Same. * gdb.python/py-section-script.py (lookup_function): Same. * gdb.python/py-unwind-inline.py (dummy_unwinder): Same. * gdb.python/python.exp: Same. * gdb.rust/pp.py (lookup_function): Same. --- gdb/doc/python.texi | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'gdb/doc/python.texi') diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi index 7b7f069..ab934a8 100644 --- a/gdb/doc/python.texi +++ b/gdb/doc/python.texi @@ -1661,7 +1661,7 @@ example above might be written. @smallexample def str_lookup_function(val): lookup_tag = val.type.tag - if lookup_tag == None: + if lookup_tag is None: return None regex = re.compile("^std::basic_string$") if regex.match(lookup_tag): -- cgit v1.1