content differently.
"""
assert_equivalent(src_contents, dst_contents)
-
- # Forced second pass to work around optional trailing commas (becoming
- # forced trailing commas on pass 2) interacting differently with optional
- # parentheses. Admittedly ugly.
- dst_contents_pass2 = format_str(dst_contents, mode=mode)
- if dst_contents != dst_contents_pass2:
- dst_contents = dst_contents_pass2
- assert_equivalent(src_contents, dst_contents, pass_num=2)
- assert_stable(src_contents, dst_contents, mode=mode)
- # Note: no need to explicitly call `assert_stable` if `dst_contents` was
- # the same as `dst_contents_pass2`.
+ assert_stable(src_contents, dst_contents, mode=mode)
def format_file_contents(src_contents: str, *, fast: bool, mode: Mode) -> FileContent:
raise NothingChanged
-def format_str(src_contents: str, *, mode: Mode) -> FileContent:
+def format_str(src_contents: str, *, mode: Mode) -> str:
"""Reformat a string and return new contents.
`mode` determines formatting options, such as how many characters per line are
hey
"""
+ dst_contents = _format_str_once(src_contents, mode=mode)
+ # Forced second pass to work around optional trailing commas (becoming
+ # forced trailing commas on pass 2) interacting differently with optional
+ # parentheses. Admittedly ugly.
+ if src_contents != dst_contents:
+ return _format_str_once(dst_contents, mode=mode)
+ return dst_contents
+
+
+def _format_str_once(src_contents: str, *, mode: Mode) -> str:
src_node = lib2to3_parse(src_contents.lstrip(), mode.target_versions)
dst_contents = []
future_imports = get_future_imports(src_node)
def assert_stable(src: str, dst: str, mode: Mode) -> None:
"""Raise AssertionError if `dst` reformats differently the second time."""
- newdst = format_str(dst, mode=mode)
+ # We shouldn't call format_str() here, because that formats the string
+ # twice and may hide a bug where we bounce back and forth between two
+ # versions.
+ newdst = _format_str_once(dst, mode=mode)
if dst != newdst:
log = dump_to_file(
str(mode),