Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/isodate/isoduration.py: 26%

1""" 

2This module provides an ISO 8601:2004 duration parser. 

3 

4It also provides a wrapper to strftime. This wrapper makes it easier to 

5format timedelta or Duration instances as ISO conforming strings. 

6""" 

7 

8import re 

9from datetime import timedelta 

10from decimal import Decimal 

11 

12from isodate.duration import Duration 

13from isodate.isodatetime import parse_datetime 

14from isodate.isoerror import ISO8601Error 

15from isodate.isostrf import D_DEFAULT, strftime 

16 

17ISO8601_PERIOD_REGEX = re.compile( 

18 r"^(?P<sign>[+-])?" 

19 r"P(?!\b)" 

20 r"(?P<years>[0-9]+([,.][0-9]+)?Y)?" 

21 r"(?P<months>[0-9]+([,.][0-9]+)?M)?" 

22 r"(?P<weeks>[0-9]+([,.][0-9]+)?W)?" 

23 r"(?P<days>[0-9]+([,.][0-9]+)?D)?" 

24 r"((?P<separator>T)(?P<hours>[0-9]+([,.][0-9]+)?H)?" 

25 r"(?P<minutes>[0-9]+([,.][0-9]+)?M)?" 

26 r"(?P<seconds>[0-9]+([,.][0-9]+)?S)?)?$" 

27) 

28# regular expression to parse ISO duration strings. 

29 

30 

31def parse_duration(datestring, as_timedelta_if_possible=True): 

32 """ 

33 Parses an ISO 8601 durations into datetime.timedelta or Duration objects. 

34 

35 If the ISO date string does not contain years or months, a timedelta 

36 instance is returned, else a Duration instance is returned. 

37 

38 The following duration formats are supported: 

39 -PnnW duration in weeks 

40 -PnnYnnMnnDTnnHnnMnnS complete duration specification 

41 -PYYYYMMDDThhmmss basic alternative complete date format 

42 -PYYYY-MM-DDThh:mm:ss extended alternative complete date format 

43 -PYYYYDDDThhmmss basic alternative ordinal date format 

44 -PYYYY-DDDThh:mm:ss extended alternative ordinal date format 

45 

46 The '-' is optional. 

47 

48 Limitations: ISO standard defines some restrictions about where to use 

49 fractional numbers and which component and format combinations are 

50 allowed. This parser implementation ignores all those restrictions and 

51 returns something when it is able to find all necessary components. 

52 In detail: 

53 it does not check, whether only the last component has fractions. 

54 it allows weeks specified with all other combinations 

55 

56 The alternative format does not support durations with years, months or 

57 days set to 0. 

58 """ 

59 if not isinstance(datestring, str): 

60 raise TypeError("Expecting a string %r" % datestring) 

61 match = ISO8601_PERIOD_REGEX.match(datestring) 

62 if not match: 

63 # try alternative format: 

64 if datestring.startswith("P"): 

65 durdt = parse_datetime(datestring[1:]) 

66 if as_timedelta_if_possible and durdt.year == 0 and durdt.month == 0: 

67 # FIXME: currently not possible in alternative format 

68 # create timedelta 

69 ret = timedelta( 

70 days=durdt.day, 

71 seconds=durdt.second, 

72 microseconds=durdt.microsecond, 

73 minutes=durdt.minute, 

74 hours=durdt.hour, 

75 ) 

76 else: 

77 # create Duration 

78 ret = Duration( 

79 days=durdt.day, 

80 seconds=durdt.second, 

81 microseconds=durdt.microsecond, 

82 minutes=durdt.minute, 

83 hours=durdt.hour, 

84 months=durdt.month, 

85 years=durdt.year, 

86 ) 

87 return ret 

88 raise ISO8601Error("Unable to parse duration string %r" % datestring) 

89 groups = match.groupdict() 

90 for key, val in groups.items(): 

91 if key not in ("separator", "sign"): 

92 if val is None: 

93 groups[key] = "0n" 

94 # print groups[key] 

95 if key in ("years", "months"): 

96 groups[key] = Decimal(groups[key][:-1].replace(",", ".")) 

97 else: 

98 # these values are passed into a timedelta object, 

99 # which works with floats. 

100 groups[key] = float(groups[key][:-1].replace(",", ".")) 

101 if as_timedelta_if_possible and groups["years"] == 0 and groups["months"] == 0: 

102 ret = timedelta( 

103 days=groups["days"], 

104 hours=groups["hours"], 

105 minutes=groups["minutes"], 

106 seconds=groups["seconds"], 

107 weeks=groups["weeks"], 

108 ) 

109 if groups["sign"] == "-": 

110 ret = timedelta(0) - ret 

111 else: 

112 ret = Duration( 

113 years=groups["years"], 

114 months=groups["months"], 

115 days=groups["days"], 

116 hours=groups["hours"], 

117 minutes=groups["minutes"], 

118 seconds=groups["seconds"], 

119 weeks=groups["weeks"], 

120 ) 

121 if groups["sign"] == "-": 

122 ret = Duration(0) - ret 

123 return ret 

124 

125 

126def duration_isoformat(tduration, format=D_DEFAULT): 

127 """ 

128 Format duration strings. 

129 

130 This method is just a wrapper around isodate.isostrf.strftime and uses 

131 P%P (D_DEFAULT) as default format. 

132 """ 

133 # TODO: implement better decision for negative Durations. 

134 # should be done in Duration class in consistent way with timedelta. 

135 if ( 

136 isinstance(tduration, Duration) 

137 and ( 

138 tduration.years < 0 

139 or tduration.months < 0 

140 or tduration.tdelta < timedelta(0) 

141 ) 

142 ) or (isinstance(tduration, timedelta) and (tduration < timedelta(0))): 

143 ret = "-" 

144 else: 

145 ret = "" 

146 ret += strftime(tduration, format) 

147 return ret