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| author | John Belmonte <john@neggie.net> | 2022-04-11 14:34:18 (GMT) |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2022-04-11 14:34:18 (GMT) |
| commit | b0b836b20cb56c225874a4a39ef895f89ab2970f (patch) | |
| tree | b333cd2e9ee95021e1fc3b45eee2da0b7ac0ee35 /Python/pystrtod.c | |
| parent | dd207a6ac52d4bd9a71cf178fc1d5c17a6f07aff (diff) | |
| download | cpython-b0b836b20cb56c225874a4a39ef895f89ab2970f.zip cpython-b0b836b20cb56c225874a4a39ef895f89ab2970f.tar.gz cpython-b0b836b20cb56c225874a4a39ef895f89ab2970f.tar.bz2 | |
bpo-45995: add "z" format specifer to coerce negative 0 to zero (GH-30049)
Add "z" format specifier to coerce negative 0 to zero.
See https://github.com/python/cpython/issues/90153 (originally https://bugs.python.org/issue45995) for discussion.
This covers `str.format()` and f-strings. Old-style string interpolation is not supported.
Co-authored-by: Mark Dickinson <dickinsm@gmail.com>
Diffstat (limited to 'Python/pystrtod.c')
| -rw-r--r-- | Python/pystrtod.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/Python/pystrtod.c b/Python/pystrtod.c index 1b27f0a..d77b846 100644 --- a/Python/pystrtod.c +++ b/Python/pystrtod.c @@ -916,6 +916,18 @@ char * PyOS_double_to_string(double val, (flags & Py_DTSF_ALT ? "#" : ""), precision, format_code); _PyOS_ascii_formatd(buf, bufsize, format, val, precision); + + if (flags & Py_DTSF_NO_NEG_0 && buf[0] == '-') { + char *buf2 = buf + 1; + while (*buf2 == '0' || *buf2 == '.') { + ++buf2; + } + if (*buf2 == 0 || *buf2 == 'e') { + size_t len = buf2 - buf + strlen(buf2); + assert(buf[len] == 0); + memmove(buf, buf+1, len); + } + } } /* Add sign when requested. It's convenient (esp. when formatting @@ -995,8 +1007,8 @@ static char * format_float_short(double d, char format_code, int mode, int precision, int always_add_sign, int add_dot_0_if_integer, - int use_alt_formatting, const char * const *float_strings, - int *type) + int use_alt_formatting, int no_negative_zero, + const char * const *float_strings, int *type) { char *buf = NULL; char *p = NULL; @@ -1022,6 +1034,11 @@ format_float_short(double d, char format_code, assert(digits_end != NULL && digits_end >= digits); digits_len = digits_end - digits; + if (no_negative_zero && sign == 1 && + (digits_len == 0 || (digits_len == 1 && digits[0] == '0'))) { + sign = 0; + } + if (digits_len && !Py_ISDIGIT(digits[0])) { /* Infinities and nans here; adapt Gay's output, so convert Infinity to inf and NaN to nan, and @@ -1301,6 +1318,7 @@ char * PyOS_double_to_string(double val, flags & Py_DTSF_SIGN, flags & Py_DTSF_ADD_DOT_0, flags & Py_DTSF_ALT, + flags & Py_DTSF_NO_NEG_0, float_strings, type); } #endif // _PY_SHORT_FLOAT_REPR == 1 |