mirror of
https://github.com/morpheus65535/bazarr
synced 2024-12-26 17:47:20 +00:00
392 lines
14 KiB
Python
392 lines
14 KiB
Python
"""
|
||
`ftfy.badness` contains a heuristic that detects likely mojibake.
|
||
|
||
This heuristic signals to ftfy which segments of text need to be fixed, and
|
||
also indicates when the text can stop being fixed.
|
||
|
||
The design of this heuristic is that we categorize the approximately 400
|
||
Unicode characters that occur in UTF-8 mojibake, specifically the characters
|
||
that come from mixing up UTF-8 with the other encodings we support. We
|
||
identify sequences and contexts of these characters that are much more likely
|
||
to be mojibake than intended strings, such as lowercase accented letters
|
||
followed immediately by currency symbols.
|
||
"""
|
||
|
||
import warnings
|
||
import re
|
||
|
||
|
||
# There are only 403 characters that occur in known UTF-8 mojibake, and we can
|
||
# characterize them:
|
||
|
||
MOJIBAKE_CATEGORIES = {
|
||
# Characters that appear in many different contexts. Sequences that contain
|
||
# them are not inherently mojibake
|
||
"common": (
|
||
"\N{NO-BREAK SPACE}"
|
||
"\N{SOFT HYPHEN}"
|
||
"\N{MIDDLE DOT}"
|
||
"\N{ACUTE ACCENT}"
|
||
"\N{EN DASH}"
|
||
"\N{EM DASH}"
|
||
"\N{HORIZONTAL BAR}"
|
||
"\N{HORIZONTAL ELLIPSIS}"
|
||
"\N{RIGHT SINGLE QUOTATION MARK}"
|
||
),
|
||
# the C1 control character range, which have no uses outside of mojibake anymore
|
||
"c1": "\x80-\x9f",
|
||
# Characters that are nearly 100% used in mojibake
|
||
"bad": (
|
||
"\N{BROKEN BAR}"
|
||
"\N{CURRENCY SIGN}"
|
||
"\N{DIAERESIS}"
|
||
"\N{NOT SIGN}"
|
||
"\N{MACRON}"
|
||
"\N{PILCROW SIGN}"
|
||
"\N{SECTION SIGN}"
|
||
"\N{CEDILLA}"
|
||
"\N{LATIN SMALL LETTER F WITH HOOK}"
|
||
"\N{MODIFIER LETTER CIRCUMFLEX ACCENT}" # it's not a modifier
|
||
"\N{CARON}"
|
||
"\N{BREVE}"
|
||
"\N{OGONEK}"
|
||
"\N{SMALL TILDE}"
|
||
"\N{DAGGER}"
|
||
"\N{DOUBLE DAGGER}"
|
||
"\N{PER MILLE SIGN}"
|
||
"\N{REVERSED NOT SIGN}"
|
||
"\N{LOZENGE}"
|
||
"\ufffd"
|
||
# Theoretically these would appear in 'numeric' contexts, but when they
|
||
# co-occur with other mojibake characters, it's not really ambiguous
|
||
"\N{FEMININE ORDINAL INDICATOR}"
|
||
"\N{MASCULINE ORDINAL INDICATOR}"
|
||
),
|
||
"currency": (
|
||
"\N{CENT SIGN}"
|
||
"\N{POUND SIGN}"
|
||
"\N{YEN SIGN}"
|
||
"\N{PESETA SIGN}"
|
||
"\N{EURO SIGN}"
|
||
),
|
||
"start_punctuation": (
|
||
"\N{INVERTED EXCLAMATION MARK}"
|
||
"\N{LEFT-POINTING DOUBLE ANGLE QUOTATION MARK}"
|
||
"\N{INVERTED QUESTION MARK}"
|
||
"\N{COPYRIGHT SIGN}"
|
||
"\N{GREEK TONOS}"
|
||
"\N{GREEK DIALYTIKA TONOS}"
|
||
"\N{LEFT SINGLE QUOTATION MARK}"
|
||
"\N{SINGLE LOW-9 QUOTATION MARK}"
|
||
"\N{LEFT DOUBLE QUOTATION MARK}"
|
||
"\N{DOUBLE LOW-9 QUOTATION MARK}"
|
||
"\N{BULLET}"
|
||
"\N{SINGLE LEFT-POINTING ANGLE QUOTATION MARK}"
|
||
"\uf8ff" # OS-specific symbol, usually the Apple logo
|
||
),
|
||
"end_punctuation": (
|
||
"\N{REGISTERED SIGN}"
|
||
"\N{RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK}"
|
||
"\N{DOUBLE ACUTE ACCENT}"
|
||
"\N{RIGHT DOUBLE QUOTATION MARK}"
|
||
"\N{SINGLE RIGHT-POINTING ANGLE QUOTATION MARK}"
|
||
"\N{TRADE MARK SIGN}"
|
||
),
|
||
"numeric": (
|
||
"\N{SUPERSCRIPT TWO}"
|
||
"\N{SUPERSCRIPT THREE}"
|
||
"\N{SUPERSCRIPT ONE}"
|
||
"\N{PLUS-MINUS SIGN}"
|
||
"\N{VULGAR FRACTION ONE QUARTER}"
|
||
"\N{VULGAR FRACTION ONE HALF}"
|
||
"\N{VULGAR FRACTION THREE QUARTERS}"
|
||
"\N{MULTIPLICATION SIGN}"
|
||
"\N{MICRO SIGN}"
|
||
"\N{DIVISION SIGN}"
|
||
"\N{FRACTION SLASH}"
|
||
"\N{PARTIAL DIFFERENTIAL}"
|
||
"\N{INCREMENT}"
|
||
"\N{N-ARY PRODUCT}"
|
||
"\N{N-ARY SUMMATION}"
|
||
"\N{SQUARE ROOT}"
|
||
"\N{INFINITY}"
|
||
"\N{INTERSECTION}"
|
||
"\N{INTEGRAL}"
|
||
"\N{ALMOST EQUAL TO}"
|
||
"\N{NOT EQUAL TO}"
|
||
"\N{IDENTICAL TO}"
|
||
"\N{LESS-THAN OR EQUAL TO}"
|
||
"\N{GREATER-THAN OR EQUAL TO}"
|
||
"\N{NUMERO SIGN}"
|
||
),
|
||
# Letters that might be used to make emoticon faces (kaomoji), and
|
||
# therefore might need to appear in more improbable-looking contexts.
|
||
#
|
||
# These are concatenated character ranges for use in a regex. I know
|
||
# they look like faces themselves. I think expressing the ranges like
|
||
# this helps to illustrate why we need to be careful with these
|
||
# characters.
|
||
"kaomoji": (
|
||
"Ò-Ö"
|
||
"Ù-Ü"
|
||
"ò-ö"
|
||
"ø-ü"
|
||
"\N{LATIN CAPITAL LETTER O WITH DOUBLE ACUTE}"
|
||
"\N{DEGREE SIGN}"
|
||
),
|
||
"upper_accented": (
|
||
# LATIN CAPITAL LETTER A WITH GRAVE - LATIN CAPITAL LETTER N WITH TILDE
|
||
"\xc0-\xd1"
|
||
# skip capital O's and U's that could be used in kaomoji, but
|
||
# include Ø because it's very common in Arabic mojibake:
|
||
"\N{LATIN CAPITAL LETTER O WITH STROKE}"
|
||
"\N{LATIN CAPITAL LETTER U WITH DIAERESIS}"
|
||
"\N{LATIN CAPITAL LETTER Y WITH ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER A WITH BREVE}"
|
||
"\N{LATIN CAPITAL LETTER A WITH OGONEK}"
|
||
"\N{LATIN CAPITAL LETTER C WITH ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER C WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER D WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER D WITH STROKE}"
|
||
"\N{LATIN CAPITAL LETTER E WITH OGONEK}"
|
||
"\N{LATIN CAPITAL LETTER E WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER G WITH BREVE}"
|
||
"\N{LATIN CAPITAL LETTER I WITH DOT ABOVE}"
|
||
"\N{LATIN CAPITAL LETTER L WITH ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER L WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER L WITH STROKE}"
|
||
"\N{LATIN CAPITAL LETTER N WITH ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER N WITH CARON}"
|
||
"\N{LATIN CAPITAL LIGATURE OE}"
|
||
"\N{LATIN CAPITAL LETTER R WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER S WITH ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER S WITH CEDILLA}"
|
||
"\N{LATIN CAPITAL LETTER S WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER T WITH CEDILLA}"
|
||
"\N{LATIN CAPITAL LETTER T WITH CARON}"
|
||
"\N{LATIN CAPITAL LETTER U WITH RING ABOVE}"
|
||
"\N{LATIN CAPITAL LETTER U WITH DOUBLE ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER Y WITH DIAERESIS}"
|
||
"\N{LATIN CAPITAL LETTER Z WITH ACUTE}"
|
||
"\N{LATIN CAPITAL LETTER Z WITH DOT ABOVE}"
|
||
"\N{LATIN CAPITAL LETTER Z WITH CARON}"
|
||
"\N{CYRILLIC CAPITAL LETTER GHE WITH UPTURN}"
|
||
),
|
||
"lower_accented": (
|
||
"\N{LATIN SMALL LETTER SHARP S}"
|
||
# LATIN SMALL LETTER A WITH GRAVE - LATIN SMALL LETTER N WITH TILDE
|
||
"\xe0-\xf1"
|
||
# skip o's and u's that could be used in kaomoji
|
||
"\N{LATIN SMALL LETTER A WITH BREVE}"
|
||
"\N{LATIN SMALL LETTER A WITH OGONEK}"
|
||
"\N{LATIN SMALL LETTER C WITH ACUTE}"
|
||
"\N{LATIN SMALL LETTER C WITH CARON}"
|
||
"\N{LATIN SMALL LETTER D WITH CARON}"
|
||
"\N{LATIN SMALL LETTER D WITH STROKE}"
|
||
"\N{LATIN SMALL LETTER E WITH OGONEK}"
|
||
"\N{LATIN SMALL LETTER E WITH CARON}"
|
||
"\N{LATIN SMALL LETTER G WITH BREVE}"
|
||
"\N{LATIN SMALL LETTER L WITH ACUTE}"
|
||
"\N{LATIN SMALL LETTER L WITH CARON}"
|
||
"\N{LATIN SMALL LETTER L WITH STROKE}"
|
||
"\N{LATIN SMALL LIGATURE OE}"
|
||
"\N{LATIN SMALL LETTER R WITH ACUTE}"
|
||
"\N{LATIN SMALL LETTER S WITH ACUTE}"
|
||
"\N{LATIN SMALL LETTER S WITH CEDILLA}"
|
||
"\N{LATIN SMALL LETTER S WITH CARON}"
|
||
"\N{LATIN SMALL LETTER T WITH CARON}"
|
||
"\N{LATIN SMALL LETTER U WITH DIAERESIS}"
|
||
"\N{LATIN SMALL LETTER Z WITH ACUTE}"
|
||
"\N{LATIN SMALL LETTER Z WITH DOT ABOVE}"
|
||
"\N{LATIN SMALL LETTER Z WITH CARON}"
|
||
"\N{CYRILLIC SMALL LETTER GHE WITH UPTURN}"
|
||
"\N{LATIN SMALL LIGATURE FI}"
|
||
"\N{LATIN SMALL LIGATURE FL}"
|
||
),
|
||
"upper_common": (
|
||
"\N{LATIN CAPITAL LETTER THORN}"
|
||
"\N{GREEK CAPITAL LETTER ALPHA}-\N{GREEK CAPITAL LETTER OMEGA}"
|
||
# not included under 'accented' because these can commonly
|
||
# occur at ends of words, in positions where they'd be detected
|
||
# as mojibake
|
||
"\N{GREEK CAPITAL LETTER ALPHA WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER EPSILON WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER ETA WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER IOTA WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER OMICRON WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER UPSILON WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER OMEGA WITH TONOS}"
|
||
"\N{GREEK CAPITAL LETTER IOTA WITH DIALYTIKA}"
|
||
"\N{GREEK CAPITAL LETTER UPSILON WITH DIALYTIKA}"
|
||
"\N{CYRILLIC CAPITAL LETTER IO}-\N{CYRILLIC CAPITAL LETTER YA}"
|
||
),
|
||
"lower_common": (
|
||
# lowercase thorn does not appear in mojibake
|
||
"\N{GREEK SMALL LETTER ALPHA}-\N{GREEK SMALL LETTER OMEGA}"
|
||
"\N{GREEK SMALL LETTER ALPHA WITH TONOS}"
|
||
"\N{GREEK SMALL LETTER EPSILON WITH TONOS}"
|
||
"\N{GREEK SMALL LETTER ETA WITH TONOS}"
|
||
"\N{GREEK SMALL LETTER IOTA WITH TONOS}"
|
||
"\N{GREEK SMALL LETTER UPSILON WITH DIALYTIKA AND TONOS}"
|
||
"\N{CYRILLIC SMALL LETTER A}-\N{CYRILLIC SMALL LETTER DZHE}"
|
||
),
|
||
"box": (
|
||
# omit the single horizontal line, might be used in kaomoji
|
||
"│┌┐┘├┤┬┼"
|
||
"\N{BOX DRAWINGS DOUBLE HORIZONTAL}-\N{BOX DRAWINGS DOUBLE VERTICAL AND HORIZONTAL}"
|
||
"▀▄█▌▐░▒▓"
|
||
),
|
||
}
|
||
|
||
|
||
# We can now build a regular expression that detects unlikely juxtapositions
|
||
# of characters, mostly based on their categories.
|
||
#
|
||
# Another regular expression, which detects sequences that look more specifically
|
||
# like UTF-8 mojibake, appears in chardata.py.
|
||
#
|
||
# This is a verbose regular expression, with whitespace added for somewhat more
|
||
# readability. Remember that the only spaces that count as literal spaces in this
|
||
# expression are ones inside character classes (square brackets).
|
||
|
||
BADNESS_RE = re.compile(
|
||
r"""
|
||
[{c1}]
|
||
|
|
||
[{bad}{lower_accented}{upper_accented}{box}{start_punctuation}{end_punctuation}{currency}{numeric}] [{bad}]
|
||
|
|
||
[a-zA-Z] [{lower_common}{upper_common}] [{bad}]
|
||
|
|
||
[{bad}] [{lower_accented}{upper_accented}{box}{start_punctuation}{end_punctuation}{currency}{numeric}]
|
||
|
|
||
[{lower_accented}{lower_common}{box}{end_punctuation}{currency}{numeric}] [{upper_accented}]
|
||
|
|
||
[{box}{end_punctuation}{currency}{numeric}] [{lower_accented}]
|
||
|
|
||
# leave out [upper_accented][currency] without further info, because it's used in some
|
||
# fancy leetspeak-esque writing
|
||
[{lower_accented}{box}{end_punctuation}] [{currency}]
|
||
|
|
||
\s [{upper_accented}] [{currency}]
|
||
|
|
||
[{upper_accented}{box}] [{numeric}]
|
||
|
|
||
[{lower_accented}{upper_accented}{box}{currency}{end_punctuation}] [{start_punctuation}] [{numeric}]
|
||
|
|
||
[{lower_accented}{upper_accented}{currency}{numeric}{box}] [{end_punctuation}] [{start_punctuation}]
|
||
|
|
||
[{currency}{numeric}{box}] [{start_punctuation}]
|
||
|
|
||
[a-z] [{upper_accented}] [{start_punctuation}{currency}]
|
||
|
|
||
[{box}] [{kaomoji}]
|
||
|
|
||
[{lower_accented}{upper_accented}{currency}{numeric}{start_punctuation}{end_punctuation}] [{box}]
|
||
|
|
||
[{box}] [{end_punctuation}]
|
||
|
|
||
[{lower_accented}{upper_accented}] [{end_punctuation}] \w
|
||
|
|
||
|
||
# The ligature œ when not followed by an unaccented Latin letter
|
||
[Œœ][^A-Za-z]
|
||
|
|
||
|
||
# Common Windows-1252 2-character mojibake that isn't covered by the cases above
|
||
[ÂÃÎÐ][€Šš¢£Ÿž\xa0\xad®©°·»{start_punctuation}{end_punctuation}–—´]
|
||
|
|
||
× [²³]
|
||
|
|
||
# Windows-1252 mojibake of Arabic words needs to include the 'common' characters.
|
||
# To compensate, we require four characters to be matched.
|
||
[ØÙ] [{common}{currency}{bad}{numeric}{start_punctuation}ŸŠ®°µ»]
|
||
[ØÙ] [{common}{currency}{bad}{numeric}{start_punctuation}ŸŠ®°µ»]
|
||
|
|
||
|
||
# Windows-1252 mojibake that starts 3-character sequences for some South Asian
|
||
# alphabets
|
||
à[²µ¹¼½¾]
|
||
|
|
||
|
||
# MacRoman mojibake that isn't covered by the cases above
|
||
√[±∂†≠®™´≤≥¥µø]
|
||
|
|
||
≈[°¢]
|
||
|
|
||
‚Ä[ìîïòôúùû†°¢π]
|
||
|
|
||
‚[âó][àä°ê]
|
||
|
|
||
|
||
# Windows-1251 mojibake of characters in the U+2000 range
|
||
вЂ
|
||
|
|
||
|
||
# Windows-1251 mojibake of Latin-1 characters and/or the Cyrillic alphabet.
|
||
# Because the 2-character sequences involved here may be common, we require
|
||
# seeing a 3-character sequence.
|
||
[ВГРС][{c1}{bad}{start_punctuation}{end_punctuation}{currency}°µ][ВГРС]
|
||
|
|
||
# A distinctive five-character sequence of Cyrillic letters, which can be
|
||
# Windows-1251 mojibake on top of Latin-1 mojibake of Windows-1252 characters.
|
||
# Require a Latin letter nearby.
|
||
ГўВЂВ.[A-Za-z ]
|
||
|
|
||
|
||
# Windows-1252 encodings of 'à' and 'á', as well as \xa0 itself
|
||
Ã[\xa0¡]
|
||
|
|
||
[a-z]\s?[ÃÂ][ ]
|
||
|
|
||
^[ÃÂ][ ]
|
||
|
|
||
|
||
# Cases where  precedes a character as an encoding of exactly the same
|
||
# character, and the character is common enough
|
||
[a-z.,?!{end_punctuation}] Â [ {start_punctuation}{end_punctuation}]
|
||
|
|
||
|
||
# Windows-1253 mojibake of characters in the U+2000 range
|
||
β€[™\xa0Ά\xad®°]
|
||
|
|
||
|
||
# Windows-1253 mojibake of Latin-1 characters and/or the Greek alphabet
|
||
[ΒΓΞΟ][{c1}{bad}{start_punctuation}{end_punctuation}{currency}°][ΒΓΞΟ]
|
||
""".format(
|
||
**MOJIBAKE_CATEGORIES
|
||
),
|
||
re.VERBOSE,
|
||
)
|
||
|
||
|
||
def sequence_weirdness(text):
|
||
"""
|
||
This was the name of the heuristic used in ftfy 2.x through 5.x. As an
|
||
attempt at compatibility with external code that calls the heuristic
|
||
directly, we redirect to our new heuristic, :func:`badness`.
|
||
"""
|
||
warnings.warn(
|
||
"`sequence_weirdness()` is an old heuristic, and the current "
|
||
"closest equivalent is `ftfy.badness.badness()`"
|
||
)
|
||
return badness(text)
|
||
|
||
|
||
def badness(text):
|
||
"""
|
||
Get the 'badness' of a sequence of text, counting the number of unlikely
|
||
character sequences. A badness greater than 0 indicates that some of it
|
||
seems to be mojibake.
|
||
"""
|
||
return len(BADNESS_RE.findall(text))
|
||
|
||
|
||
def is_bad(text):
|
||
"""
|
||
Returns true iff the given text looks like it contains mojibake.
|
||
|
||
This can be faster than `badness`, because it returns when the first match
|
||
is found to a regex instead of counting matches. Note that as strings get
|
||
longer, they have a higher chance of returning True for `is_bad(string)`.
|
||
"""
|
||
return bool(BADNESS_RE.search(text))
|