Coverage for /usr/local/lib/python3.7/dist-packages/chardet/latin1prober.py : 42%

######################## BEGIN LICENSE BLOCK ######################## 

# The Original Code is Mozilla Universal charset detector code. 

# 

# The Initial Developer of the Original Code is 

# Netscape Communications Corporation. 

# Portions created by the Initial Developer are Copyright (C) 2001 

# the Initial Developer. All Rights Reserved. 

# 

# Contributor(s): 

# Mark Pilgrim - port to Python 

# Shy Shalom - original C code 

# 

# This library is free software; you can redistribute it and/or 

# modify it under the terms of the GNU Lesser General Public 

# License as published by the Free Software Foundation; either 

# version 2.1 of the License, or (at your option) any later version. 

# 

# This library is distributed in the hope that it will be useful, 

# but WITHOUT ANY WARRANTY; without even the implied warranty of 

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 

# Lesser General Public License for more details. 

# 

# You should have received a copy of the GNU Lesser General Public 

# License along with this library; if not, write to the Free Software 

# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 

# 02110-1301 USA 

######################### END LICENSE BLOCK ######################### 

from .charsetprober import CharSetProber 

from .enums import ProbingState 

FREQ_CAT_NUM = 4 

UDF = 0 # undefined 

OTH = 1 # other 

ASC = 2 # ascii capital letter 

ASS = 3 # ascii small letter 

ACV = 4 # accent capital vowel 

ACO = 5 # accent capital other 

ASV = 6 # accent small vowel 

ASO = 7 # accent small other 

CLASS_NUM = 8 # total classes 

Latin1_CharToClass = ( 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 00 - 07 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 08 - 0F 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 10 - 17 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 18 - 1F 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 20 - 27 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 28 - 2F 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 30 - 37 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 38 - 3F 

OTH, ASC, ASC, ASC, ASC, ASC, ASC, ASC, # 40 - 47 

ASC, ASC, ASC, ASC, ASC, ASC, ASC, ASC, # 48 - 4F 

ASC, ASC, ASC, ASC, ASC, ASC, ASC, ASC, # 50 - 57 

ASC, ASC, ASC, OTH, OTH, OTH, OTH, OTH, # 58 - 5F 

OTH, ASS, ASS, ASS, ASS, ASS, ASS, ASS, # 60 - 67 

ASS, ASS, ASS, ASS, ASS, ASS, ASS, ASS, # 68 - 6F 

ASS, ASS, ASS, ASS, ASS, ASS, ASS, ASS, # 70 - 77 

ASS, ASS, ASS, OTH, OTH, OTH, OTH, OTH, # 78 - 7F 

OTH, UDF, OTH, ASO, OTH, OTH, OTH, OTH, # 80 - 87 

OTH, OTH, ACO, OTH, ACO, UDF, ACO, UDF, # 88 - 8F 

UDF, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 90 - 97 

OTH, OTH, ASO, OTH, ASO, UDF, ASO, ACO, # 98 - 9F 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # A0 - A7 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # A8 - AF 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # B0 - B7 

OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # B8 - BF 

ACV, ACV, ACV, ACV, ACV, ACV, ACO, ACO, # C0 - C7 

ACV, ACV, ACV, ACV, ACV, ACV, ACV, ACV, # C8 - CF 

ACO, ACO, ACV, ACV, ACV, ACV, ACV, OTH, # D0 - D7 

ACV, ACV, ACV, ACV, ACV, ACO, ACO, ACO, # D8 - DF 

ASV, ASV, ASV, ASV, ASV, ASV, ASO, ASO, # E0 - E7 

ASV, ASV, ASV, ASV, ASV, ASV, ASV, ASV, # E8 - EF 

ASO, ASO, ASV, ASV, ASV, ASV, ASV, OTH, # F0 - F7 

ASV, ASV, ASV, ASV, ASV, ASO, ASO, ASO, # F8 - FF 

) 

# 0 : illegal 

# 1 : very unlikely 

# 2 : normal 

# 3 : very likely 

Latin1ClassModel = ( 

# UDF OTH ASC ASS ACV ACO ASV ASO 

0, 0, 0, 0, 0, 0, 0, 0, # UDF 

0, 3, 3, 3, 3, 3, 3, 3, # OTH 

0, 3, 3, 3, 3, 3, 3, 3, # ASC 

0, 3, 3, 3, 1, 1, 3, 3, # ASS 

0, 3, 3, 3, 1, 2, 1, 2, # ACV 

0, 3, 3, 3, 3, 3, 3, 3, # ACO 

0, 3, 1, 3, 1, 1, 1, 3, # ASV 

0, 3, 1, 3, 1, 1, 3, 3, # ASO 

) 

class Latin1Prober(CharSetProber): 

def __init__(self): 

super(Latin1Prober, self).__init__() 

self._last_char_class = None 

self._freq_counter = None 

self.reset() 

def reset(self): 

self._last_char_class = OTH 

self._freq_counter = [0] * FREQ_CAT_NUM 

CharSetProber.reset(self) 

@property 

def charset_name(self): 

return "ISO-8859-1" 

@property 

def language(self): 

return "" 

def feed(self, byte_str): 

byte_str = self.filter_with_english_letters(byte_str) 

for c in byte_str: 

char_class = Latin1_CharToClass[c] 

freq = Latin1ClassModel[(self._last_char_class * CLASS_NUM) 

+ char_class] 

if freq == 0: 

self._state = ProbingState.NOT_ME 

break 

self._freq_counter[freq] += 1 

self._last_char_class = char_class 

return self.state 

def get_confidence(self): 

if self.state == ProbingState.NOT_ME: 

return 0.01 

total = sum(self._freq_counter) 

if total < 0.01: 

confidence = 0.0 

else: 

confidence = ((self._freq_counter[3] - self._freq_counter[1] * 20.0) 

/ total) 

if confidence < 0.0: 

confidence = 0.0 

# lower the confidence of latin1 so that other more accurate 

# detector can take priority. 

confidence = confidence * 0.73 

return confidence