# Copyright (c) 2004 Python Software Foundation.
# All rights reserved.

# Written by Eric Price <eprice at tjhsst.edu>
#    and Facundo Batista <facundo at taniquetil.com.ar>
#    and Raymond Hettinger <python at rcn.com>
#    and Aahz (aahz at pobox.com)
#    and Tim Peters

"""
These are the test cases for the Decimal module.

There are two groups of tests, Arithmetic and Behaviour. The former test
the Decimal arithmetic using the tests provided by Mike Cowlishaw. The latter
test the pythonic behaviour according to PEP 327.

Cowlishaw's tests can be downloaded from:

   http://speleotrove.com/decimal/dectest.zip

This test module can be called from command line with one parameter (Arithmetic
or Behaviour) to test each part, or without parameter to test both parts. If
you're working through IDLE, you can import this test module and call test_main()
with the corresponding argument.
"""

import math
import os, sys
import operator
import warnings
import pickle, copy
import unittest
import numbers
import locale
from test.support import (run_unittest, run_doctest, is_resource_enabled,
                          requires_IEEE_754, requires_docstrings)
from test.support import (import_fresh_module, TestFailed,
                          run_with_locale, cpython_only)
import random
import inspect
import threading


C = import_fresh_module('decimal', fresh=['_decimal'])
P = import_fresh_module('decimal', blocked=['_decimal'])
orig_sys_decimal = sys.modules['decimal']

# fractions module must import the correct decimal module.
cfractions = import_fresh_module('fractions', fresh=['fractions'])
sys.modules['decimal'] = P
pfractions = import_fresh_module('fractions', fresh=['fractions'])
sys.modules['decimal'] = C
fractions = {C:cfractions, P:pfractions}
sys.modules['decimal'] = orig_sys_decimal


# Useful Test Constant
Signals = {
  C: tuple(C.getcontext().flags.keys()) if C else None,
  P: tuple(P.getcontext().flags.keys())
}
# Signals ordered with respect to precedence: when an operation
# produces multiple signals, signals occurring later in the list
# should be handled before those occurring earlier in the list.
OrderedSignals = {
  C: [C.Clamped, C.Rounded, C.Inexact, C.Subnormal, C.Underflow,
      C.Overflow, C.DivisionByZero, C.InvalidOperation,
      C.FloatOperation] if C else None,
  P: [P.Clamped, P.Rounded, P.Inexact, P.Subnormal, P.Underflow,
      P.Overflow, P.DivisionByZero, P.InvalidOperation,
      P.FloatOperation]
}
def assert_signals(cls, context, attr, expected):
    d = getattr(context, attr)
    cls.assertTrue(all(d[s] if s in expected else not d[s] for s in d))

ROUND_UP = P.ROUND_UP
ROUND_DOWN = P.ROUND_DOWN
ROUND_CEILING = P.ROUND_CEILING
ROUND_FLOOR = P.ROUND_FLOOR
ROUND_HALF_UP = P.ROUND_HALF_UP
ROUND_HALF_DOWN = P.ROUND_HALF_DOWN
ROUND_HALF_EVEN = P.ROUND_HALF_EVEN
ROUND_05UP = P.ROUND_05UP

RoundingModes = [
  ROUND_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR,
  ROUND_HALF_UP, ROUND_HALF_DOWN, ROUND_HALF_EVEN,
  ROUND_05UP
]

# Tests are built around these assumed context defaults.
# test_main() restores the original context.
ORIGINAL_CONTEXT = {
  C: C.getcontext().copy() if C else None,
  P: P.getcontext().copy()
}
def init(m):
    if not m: return
    DefaultTestContext = m.Context(
       prec=9, rounding=ROUND_HALF_EVEN, traps=dict.fromkeys(Signals[m], 0)
    )
    m.setcontext(DefaultTestContext)

TESTDATADIR = 'decimaltestdata'
if __name__ == '__main__':
    file = sys.argv[0]
else:
    file = __file__
testdir = os.path.dirname(file) or os.curdir
directory = testdir + os.sep + TESTDATADIR + os.sep

skip_expected = not os.path.isdir(directory)

# Make sure it actually raises errors when not expected and caught in flags
# Slower, since it runs some things several times.
EXTENDEDERRORTEST = False

# Test extra functionality in the C version (-DEXTRA_FUNCTIONALITY).
EXTRA_FUNCTIONALITY = True if hasattr(C, 'DecClamped') else False
requires_extra_functionality = unittest.skipUnless(
  EXTRA_FUNCTIONALITY, "test requires build with -DEXTRA_FUNCTIONALITY")
skip_if_extra_functionality = unittest.skipIf(
  EXTRA_FUNCTIONALITY, "test requires regular build")


class IBMTestCases(unittest.TestCase):
    """Class which tests the Decimal class against the IBM test cases."""

    def setUp(self):
        self.context = self.decimal.Context()
        self.readcontext = self.decimal.Context()
        self.ignore_list = ['#']

        # List of individual .decTest test ids that correspond to tests that
        # we're skipping for one reason or another.
        self.skipped_test_ids = set([
            # Skip implementation-specific scaleb tests.
            'scbx164',
            'scbx165',

            # For some operations (currently exp, ln, log10, power), the decNumber
            # reference implementation imposes additional restrictions on the context
            # and operands.  These restrictions are not part of the specification;
            # however, the effect of these restrictions does show up in some of the
            # testcases.  We skip testcases that violate these restrictions, since
            # Decimal behaves differently from decNumber for these testcases so these
            # testcases would otherwise fail.
            'expx901',
            'expx902',
            'expx903',
            'expx905',
            'lnx901',
            'lnx902',
            'lnx903',
            'lnx905',
            'logx901',
            'logx902',
            'logx903',
            'logx905',
            'powx1183',
            'powx1184',
            'powx4001',
            'powx4002',
            'powx4003',
            'powx4005',
            'powx4008',
            'powx4010',
            'powx4012',
            'powx4014',
            ])

        if self.decimal == C:
            # status has additional Subnormal, Underflow
            self.skipped_test_ids.add('pwsx803')
            self.skipped_test_ids.add('pwsx805')
            # Correct rounding (skipped for decNumber, too)
            self.skipped_test_ids.add('powx4302')
            self.skipped_test_ids.add('powx4303')
            self.skipped_test_ids.add('powx4342')
            self.skipped_test_ids.add('powx4343')
            # http://bugs.python.org/issue7049
            self.skipped_test_ids.add('pwmx325')
            self.skipped_test_ids.add('pwmx326')

        # Map test directives to setter functions.
        self.ChangeDict = {'precision' : self.change_precision,
                           'rounding' : self.change_rounding_method,
                           'maxexponent' : self.change_max_exponent,
                           'minexponent' : self.change_min_exponent,
                           'clamp' : self.change_clamp}

        # Name adapter to be able to change the Decimal and Context
        # interface without changing the test files from Cowlishaw.
        self.NameAdapter = {'and':'logical_and',
                            'apply':'_apply',
                            'class':'number_class',
                            'comparesig':'compare_signal',
                            'comparetotal':'compare_total',
                            'comparetotmag':'compare_total_mag',
                            'copy':'copy_decimal',
                            'copyabs':'copy_abs',
                            'copynegate':'copy_negate',
                            'copysign':'copy_sign',
                            'divideint':'divide_int',
                            'invert':'logical_invert',
                            'iscanonical':'is_canonical',
                            'isfinite':'is_finite',
                            'isinfinite':'is_infinite',
                            'isnan':'is_nan',
                            'isnormal':'is_normal',
                            'isqnan':'is_qnan',
                            'issigned':'is_signed',
                            'issnan':'is_snan',
                            'issubnormal':'is_subnormal',
                            'iszero':'is_zero',
                            'maxmag':'max_mag',
                            'minmag':'min_mag',
                            'nextminus':'next_minus',
                            'nextplus':'next_plus',
                            'nexttoward':'next_toward',
                            'or':'logical_or',
                            'reduce':'normalize',
                            'remaindernear':'remainder_near',
                            'samequantum':'same_quantum',
                            'squareroot':'sqrt',
                            'toeng':'to_eng_string',
                            'tointegral':'to_integral_value',
                            'tointegralx':'to_integral_exact',
                            'tosci':'to_sci_string',
                            'xor':'logical_xor'}

        # Map test-case names to roundings.
        self.RoundingDict = {'ceiling' : ROUND_CEILING,
                             'down' : ROUND_DOWN,
                             'floor' : ROUND_FLOOR,
                             'half_down' : ROUND_HALF_DOWN,
                             'half_even' : ROUND_HALF_EVEN,
                             'half_up' : ROUND_HALF_UP,
                             'up' : ROUND_UP,
                             '05up' : ROUND_05UP}

        # Map the test cases' error names to the actual errors.
        self.ErrorNames = {'clamped' : self.decimal.Clamped,
                           'conversion_syntax' : self.decimal.InvalidOperation,
                           'division_by_zero' : self.decimal.DivisionByZero,
                           'division_impossible' : self.decimal.InvalidOperation,
                           'division_undefined' : self.decimal.InvalidOperation,
                           'inexact' : self.decimal.Inexact,
                           'invalid_context' : self.decimal.InvalidOperation,
                           'invalid_operation' : self.decimal.InvalidOperation,
                           'overflow' : self.decimal.Overflow,
                           'rounded' : self.decimal.Rounded,
                           'subnormal' : self.decimal.Subnormal,
                           'underflow' : self.decimal.Underflow}

        # The following functions return True/False rather than a
        # Decimal instance.
        self.LogicalFunctions = ('is_canonical',
                                 'is_finite',
                                 'is_infinite',
                                 'is_nan',
                                 'is_normal',
                                 'is_qnan',
                                 'is_signed',
                                 'is_snan',
                                 'is_subnormal',
                                 'is_zero',
                                 'same_quantum')

    def read_unlimited(self, v, context):
        """Work around the limitations of the 32-bit _decimal version. The
           guaranteed maximum values for prec, Emax etc. are 425000000,
           but higher values usually work, except for rare corner cases.
           In particular, all of the IBM tests pass with maximum values
           of 1070000000."""
        if self.decimal == C and self.decimal.MAX_EMAX == 425000000:
            self.readcontext._unsafe_setprec(1070000000)
            self.readcontext._unsafe_setemax(1070000000)
            self.readcontext._unsafe_setemin(-1070000000)
            return self.readcontext.create_decimal(v)
        else:
            return self.decimal.Decimal(v, context)

    def eval_file(self, file):
        global skip_expected
        if skip_expected:
            raise unittest.SkipTest
        with open(file) as f:
            for line in f:
                line = line.replace('\r\n', '').replace('\n', '')
                #print line
                try:
                    t = self.eval_line(line)
                except self.decimal.DecimalException as exception:
                    #Exception raised where there shouldn't have been one.
                    self.fail('Exception "'+exception.__class__.__name__ + '" raised on line '+line)


    def eval_line(self, s):
        if s.find(' -> ') >= 0 and s[:2] != '--' and not s.startswith('  --'):
            s = (s.split('->')[0] + '->' +
                 s.split('->')[1].split('--')[0]).strip()
        else:
            s = s.split('--')[0].strip()

        for ignore in self.ignore_list:
            if s.find(ignore) >= 0:
                #print s.split()[0], 'NotImplemented--', ignore
                return
        if not s:
            return
        elif ':' in s:
            return self.eval_directive(s)
        else:
            return self.eval_equation(s)

    def eval_directive(self, s):
        funct, value = (x.strip().lower() for x in s.split(':'))
        if funct == 'rounding':
            value = self.RoundingDict[value]
        else:
            try:
                value = int(value)
            except ValueError:
                pass

        funct = self.ChangeDict.get(funct, (lambda *args: None))
        funct(value)

    def eval_equation(self, s):

        if not TEST_ALL and random.random() < 0.90:
            return

        self.context.clear_flags()

        try:
            Sides = s.split('->')
            L = Sides[0].strip().split()
            id = L[0]
            if DEBUG:
                print("Test ", id, end=" ")
            funct = L[1].lower()
            valstemp = L[2:]