Walkthrough

String format specifications now track explicit alignment, reject =...s, and expose the new error as ValueError. Tests cover string zero padding, explicit alignment rejection, and integer sign-aware zero padding.

Changes

String alignment validation

Estimated code review effort: 3 (Moderate) | ~20 minutes

Possibly related PRs

• RustPython/RustPython#7769: Modifies the same string formatting path while changing precision and alignment handling.

Suggested reviewers: changjoon-park, shaharnaveh

❌ Failed checks (1 warning)

• Create PR with unit tests

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

• X
• Mastodon
• Reddit
• LinkedIn

Comment @coderabbitai help to get the list of available commands.

📦 Library Dependencies

The following Lib/ modules were modified. Here are their dependencies:

[x] test: cpython/Lib/test/test_binascii.py (TODO: 4)

dependencies:

dependent tests: (95 tests)

• binascii: test_base64 test_binascii test_codecs test_ctypes test_descr test_hashlib test_hmac test_plistlib test_struct test_zlib
  • base64: test_email test_gettext test_httpservers test_smtplib test_urllib2 test_urllib2_localnet test_xmlrpc test_zoneinfo
    • http.server: test_logging test_robotparser
    • logging.handlers: test_concurrent_futures test_pkgutil
    • secrets: test_secrets
    • smtplib: test_smtpnet
    • ssl: test_asyncio test_ftplib test_httplib test_imaplib test_poplib test_ssl test_urllib test_venv
    • urllib.request: test_http_cookiejar test_pathlib test_pydoc test_sax test_site test_urllib2net test_urllibnet
  • email: test_email test_mailbox test_zipfile
    • importlib.metadata: test_importlib
    • mailbox: test_genericalias
    • pydoc: test_enum
  • http.server:
    • wsgiref.simple_server: test_wsgiref
  • plistlib:
    • platform: test__locale test__osx_support test_asyncio test_baseexception test_builtin test_cmath test_ctypes test_fcntl test_math test_mimetypes test_os test_platform test_posix test_regrtest test_shutil test_socket test_strptime test_sysconfig test_time test_winreg
  • quopri: test_quopri
  • zipfile: test_pdb test_zipapp test_zipfile test_zipfile64 test_zipimport test_zipimport_support
    • shutil: test_argparse test_bz2 test_compileall test_ctypes test_embed test_filecmp test_glob test_importlib test_inspect test_largefile test_launcher test_modulefinder test_peg_generator test_py_compile test_reprlib test_string_literals test_subprocess test_support test_tarfile test_tempfile test_traceback test_unicode_file

[ ] lib: cpython/Lib/unittest
[x] test: cpython/Lib/test/test_unittest (TODO: 11)

dependencies:

• unittest (native: _io, _log, async_case, builtins, case, loader, main, os.path, result, runner, signals, suite, sys, time, unittest.util, util)
  • warnings (native: _contextvars, _thread, _warnings, builtins, sys)
  • _colorize, annotationlib, argparse, asyncio, collections, contextlib, contextvars, dataclasses, difflib, fnmatch, functools, inspect, io, logging, os, pkgutil, pprint, re, signal, threading, traceback, types, weakref

dependent tests: (408 tests)

• unittest: regrtestdata test___all__ test__colorize test__locale test__opcode test__osx_support test_abc test_abstract_numbers test_android test_annotationlib test_apple test_argparse test_array test_asdl_parser test_ast test_asyncgen test_asyncio test_atexit test_audit test_augassign test_base64 test_baseexception test_bdb test_bigaddrspace test_bigmem test_binascii test_binop test_bisect test_bool test_buffer test_bufio test_builtin test_bytes test_bz2 test_c_locale_coercion test_calendar test_call test_charmapcodec test_class test_clinic test_cmath test_cmd test_cmd_line test_cmd_line_script test_code test_code_module test_codeccallbacks test_codecencodings_cn test_codecencodings_hk test_codecencodings_iso2022 test_codecencodings_jp test_codecencodings_kr test_codecencodings_tw test_codecmaps_cn test_codecmaps_hk test_codecmaps_jp test_codecmaps_kr test_codecmaps_tw test_codecs test_codeop test_collections test_colorsys test_compare test_compile test_compileall test_complex test_concurrent_futures test_configparser test_contains test_context test_contextlib test_contextlib_async test_copy test_copyreg test_coroutines test_cprofile test_csv test_ctypes test_datetime test_dbm test_dbm_dumb test_dbm_sqlite3 test_decimal test_decorators test_defaultdict test_deque test_descr test_descrtut test_devpoll test_dict test_dictcomps test_dictviews test_difflib test_dis test_doctest test_doctest2 test_docxmlrpc test_dtrace test_dummy_thread test_dummy_threading test_dynamic test_dynamicclassattribute test_eintr test_email test_embed test_ensurepip test_enum test_enumerate test_eof test_epoll test_errno test_except_star test_exception_group test_exception_hierarchy test_exception_variations test_exceptions test_extcall test_external_inspection test_faulthandler test_fcntl test_file test_file_eintr test_filecmp test_fileinput test_fileio test_fileutils test_finalization test_float test_flufl test_fnmatch test_fork1 test_format test_fractions test_frame test_frozen test_fstring test_ftplib test_funcattrs test_functools test_future_stmt test_gc test_generated_cases test_generator_stop test_generators test_genericalias test_genericclass test_genericpath test_genexps test_getopt test_getpass test_gettext test_glob test_global test_grammar test_graphlib test_grp test_gzip test_hash test_hashlib test_heapq test_hmac test_html test_htmlparser test_http_cookiejar test_http_cookies test_httplib test_httpservers test_idle test_imaplib test_importlib test_index test_inspect test_int test_int_literal test_io test_ioctl test_ipaddress test_isinstance test_iter test_iterlen test_itertools test_json test_keyword test_keywordonlyarg test_kqueue test_largefile test_launcher test_linecache test_list test_listcomps test_locale test_logging test_long test_longexp test_lzma test_mailbox test_marshal test_math test_math_property test_memoryio test_memoryview test_metaclass test_mimetypes test_minidom test_mmap test_modulefinder test_monitoring test_msvcrt test_multibytecodec test_multiprocessing_fork test_multiprocessing_forkserver test_multiprocessing_main_handling test_multiprocessing_spawn test_named_expressions test_netrc test_ntpath test_nturl2path test_numeric_tower test_opcache test_opcodes test_openpty test_operator test_optimizer test_optparse test_ordered_dict test_os test_osx_env test_pathlib test_patma test_pdb test_peepholer test_peg_generator test_pep646_syntax test_perfmaps test_pickle test_picklebuffer test_pickletools test_pkg test_pkgutil test_platform test_plistlib test_poll test_popen test_poplib test_positional_only_arg test_posix test_posixpath test_pow test_pprint test_print test_profile test_property test_pstats test_pty test_pulldom test_pwd test_py_compile test_pyclbr test_pydoc test_pyexpat test_pyrepl test_queue test_quopri test_raise test_random test_range test_re test_regrtest test_repl test_reprlib test_resource test_richcmp test_rlcompleter test_robotparser test_runpy test_sax test_sched test_scope test_script_helper test_secrets test_select test_selectors test_set test_setcomps test_shelve test_shlex test_shutil test_signal test_site test_slice test_smtplib test_smtpnet test_socket test_socketserver test_sort test_sqlite3 test_ssl test_stable_abi_ctypes test_stat test_statistics test_str test_strftime test_string test_string_literals test_stringprep test_strptime test_strtod test_struct test_structseq test_subclassinit test_subprocess test_sundry test_super test_support test_symtable test_syntax test_sys test_sys_setprofile test_sys_settrace test_sysconfig test_syslog test_tabnanny test_tarfile test_tempfile test_termios test_textwrap test_thread test_thread_local_bytecode test_threadedtempfile test_threading test_threading_local test_threadsignals test_time test_timeit test_timeout test_tokenize test_tomllib test_tools test_trace test_traceback test_tracemalloc test_tstring test_tty test_tuple test_turtle test_type_aliases test_type_annotations test_type_cache test_type_comments test_type_params test_typechecks test_types test_typing test_ucn test_unary test_unicode_file test_unicode_file_functions test_unicode_identifiers test_unicodedata test_unittest test_univnewlines test_unpack test_unpack_ex test_unparse test_urllib test_urllib2 test_urllib2_localnet test_urllib2net test_urllib_response test_urllibnet test_urlparse test_userdict test_userlist test_userstring test_utf8_mode test_utf8source test_uuid test_venv test_wait3 test_wait4 test_wave test_weakref test_weakset test_webbrowser test_winapi test_winconsoleio test_winreg test_winsound test_with test_wmi test_wsgiref test_xml_dom_minicompat test_xml_dom_xmlbuilder test_xml_etree test_xml_etree_c test_xmlrpc test_xpickle test_xxlimited test_xxtestfuzz test_yield_from test_zipapp test_zipfile test_zipfile64 test_zipimport test_zipimport_support test_zlib test_zoneinfo test_zstd

[x] test: cpython/Lib/test/test_str.py (TODO: 6)
[x] test: cpython/Lib/test/test_fstring.py (TODO: 14)
[x] test: cpython/Lib/test/test_string_literals.py (TODO: 4)

dependencies:

dependent tests: (no tests depend on str)

[x] lib: cpython/Lib/pdb.py
[ ] test: cpython/Lib/test/test_pdb.py (TODO: 46)

dependencies:

• pdb

dependent tests: (1 tests)

• pdb: test_pdb

[x] lib: cpython/Lib/inspect.py
[ ] test: cpython/Lib/test/test_inspect (TODO: 32)

dependencies:

• inspect

dependent tests: (96 tests)

• inspect: test_abc test_argparse test_asyncgen test_buffer test_builtin test_clinic test_code test_collections test_coroutines test_decimal test_enum test_functools test_generators test_grammar test_inspect test_monitoring test_ntpath test_operator test_patma test_posixpath test_pydoc test_signal test_sqlite3 test_traceback test_turtle test_type_annotations test_types test_typing test_unittest test_yield_from test_zipimport test_zipimport_support test_zoneinfo
  • ast: test_ast test_compile test_compiler_codegen test_dis test_fstring test_future_stmt test_peepholer test_peg_generator test_site test_ssl test_type_comments test_ucn test_unparse
    • annotationlib: test_annotationlib test_reprlib test_type_params
    • dbm.dumb: test_dbm_dumb
    • pyclbr: test_pyclbr
    • traceback: test_asyncio test_code_module test_contextlib test_contextlib_async test_dictcomps test_exceptions test_http_cookiejar test_importlib test_iter test_listcomps test_pyexpat test_setcomps test_socket test_subprocess test_sys test_threadedtempfile test_threading test_unittest test_with
  • asyncio: test_asyncio test_external_inspection test_logging test_os test_pdb
  • bdb: test_bdb
  • cmd: test_cmd
    • pstats: test_profile test_pstats
  • dataclasses: test__colorize test_copy test_ctypes test_genericalias test_pprint test_regrtest
    • pprint: test_htmlparser test_sys_setprofile
  • importlib.metadata: test_importlib
  • pkgutil: test_pkgutil test_pyrepl test_runpy
  • pydoc:
    • xmlrpc.server: test_docxmlrpc test_xmlrpc
  • rlcompleter: test_pyrepl test_rlcompleter
  • trace: test_trace

[x] lib: cpython/Lib/sqlite3
[x] test: cpython/Lib/test/test_sqlite3 (TODO: 69)

dependencies:

• sqlite3

dependent tests: (2 tests)

• sqlite3: test_dbm_sqlite3 test_sqlite3

[x] lib: cpython/Lib/pydoc.py
[x] lib: cpython/Lib/pydoc_data
[ ] test: cpython/Lib/test/test_pydoc (TODO: 33)

dependencies:

• pydoc

dependent tests: (5 tests)

• pydoc: test_enum test_pydoc
  • pdb: test_pdb
  • xmlrpc.server: test_docxmlrpc test_xmlrpc

[x] lib: cpython/Lib/re
[x] lib: cpython/Lib/sre_compile.py
[x] lib: cpython/Lib/sre_constants.py
[x] lib: cpython/Lib/sre_parse.py
[ ] test: cpython/Lib/test/test_re.py (TODO: 11)
[x] test: cpython/Lib/test/re_tests.py

dependencies:

• re

dependent tests: (81 tests)

• re: test_android test_ast test_asyncio test_binascii test_builtin test_bytes test_clinic test_cmd_line test_ctypes test_dict test_dis test_docxmlrpc test_dtrace test_email test_embed test_faulthandler test_filecmp test_fileinput test_fnmatch test_format test_frame test_fstring test_functools test_future_stmt test_generated_cases test_genericalias test_glob test_hashlib test_http_cookiejar test_httplib test_httpservers test_imaplib test_importlib test_inspect test_ipaddress test_launcher test_logging test_mailbox test_mmap test_optparse test_ordered_dict test_platform test_pprint test_pydoc test_pyexpat test_pyrepl test_re test_regrtest test_runpy test_set test_site test_smtplib test_socket test_ssl test_strftime test_strptime test_strtod test_structseq test_symtable test_syntax test_sys test_sysconfig test_tarfile test_tempfile test_tokenize test_tools test_traceback test_turtle test_typing test_unittest test_unparse test_venv test_webbrowser test_winapi test_with test_wsgiref test_xmlrpc test_zipfile test_zipimport test_zoneinfo test_zstd

Legend:

• [+] path exists in CPython
• [x] up-to-date, [ ] outdated