#
#  verify.py:  routines that handle comparison and display of expected
#              vs. actual output
#
#  Subversion is a tool for revision control.
#  See http://subversion.tigris.org for more information.
#
# ====================================================================
# Copyright (c) 2000-2007 CollabNet.  All rights reserved.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution.  The terms
# are also available at http://subversion.tigris.org/license-1.html.
# If newer versions of this license are posted there, you may use a
# newer version instead, at your option.
#
######################################################################

import re, sys

import main, tree, wc  # general svntest routines in this module.
from svntest import Failure

######################################################################
# Exception types

class SVNUnexpectedOutput(Failure):
  """Exception raised if an invocation of svn results in unexpected
  output of any kind."""
  pass

class SVNUnexpectedStdout(SVNUnexpectedOutput):
  """Exception raised if an invocation of svn results in unexpected
  output on STDOUT."""
  pass

class SVNUnexpectedStderr(SVNUnexpectedOutput):
  """Exception raised if an invocation of svn results in unexpected
  output on STDERR."""
  pass

class SVNExpectedStdout(SVNUnexpectedOutput):
  """Exception raised if an invocation of svn results in no output on
  STDOUT when output was expected."""
  pass

class SVNExpectedStderr(SVNUnexpectedOutput):
  """Exception raised if an invocation of svn results in no output on
  STDERR when output was expected."""
  pass

class SVNIncorrectDatatype(SVNUnexpectedOutput):
  """Exception raised if invalid input is passed to the
  run_and_verify_* API"""
  pass


######################################################################
# Comparison of expected vs. actual output

def createExpectedOutput(expected):
  """Return EXPECTED, promoted to an ExpectedOutput instance if not
  None.  Raise SVNIncorrectDatatype if the data type of EXPECTED is
  not handled."""
  if isinstance(expected, type([])):
    expected = ExpectedOutput(expected)
  elif isinstance(expected, type('')):
    expected = RegexOutput(expected, False)
  elif expected == AnyOutput:
    expected = AnyOutput()
  elif expected is not None and not isinstance(expected, ExpectedOutput):
    raise SVNIncorrectDatatype("Unexpected type for '%s' data" % output_type)
  return expected

class ExpectedOutput:
  """Contains expected output, and performs comparisions."""
  def __init__(self, output, match_all=True):
    """Set SELF.output (which may be None).  If MATCH_ALL is True,
    require that all lines from OUTPUT match when performing
    comparsisons.  If False, allow any lines to match."""
    self.output = output
    self.match_all = match_all

  def __str__(self):
    return str(self.output)

  def __cmp__(self, other):
    """Return whether SELF.output matches OTHER (which may be a list
    of newline-terminated lines, or a single string).  Either value
    may be None."""
    if self.output is None:
      expected = []
    else:
      expected = self.output
    if other is None:
      actual = []
    else:
      actual = other

    if isinstance(actual, list):
      if isinstance(expected, type('')):
        expected = [expected]
      is_match = self.is_equivalent_list(expected, actual)
    elif isinstance(actual, type('')):
      is_match = self.is_equivalent_line(expected, actual)
    else: # unhandled type
      is_match = False

    if is_match:
      return 0
    else:
      return 1

  def is_equivalent_list(self, expected, actual):
    "Return whether EXPECTED and ACTUAL are equivalent."
    if self.match_all:
      if len(expected) != len(actual):
        return False
      for i in range(0, len(actual)):
        if not self.is_equivalent_line(expected[i], actual[i]):
          return False
      return True
    else:
      for expected_re in expected:
        for i in range(0, len(actual)):
          if self.is_equivalent_line(expected_re, actual[i]):
            return True
      return False

  def is_equivalent_line(self, expected, actual):
    "Return whether EXPECTED and ACTUAL are equal."
    return expected == actual

  def display_differences(self, message, label, actual):
    """Delegate to the display_lines() routine with the appropriate
    args.  MESSAGE is ignored if None."""
    display_lines(message, label, self.output, actual, False, False)

class AnyOutput(ExpectedOutput):
  def __init__(self):
    ExpectedOutput.__init__(self, None, False)

  def is_equivalent_list(self, ignored, actual):
    if len(actual) == 0:
      # Empty text or empty list -- either way, no output!
      return False
    elif isinstance(actual, list):
      for line in actual:
        if self.is_equivalent_line(None, line):
          return True
      return False
    else:
      return True

  def is_equivalent_line(self, ignored, actual):
    return len(actual) > 0

  def display_differences(self, message, label, actual):
    if message:
      print message

class RegexOutput(ExpectedOutput):
  def is_equivalent_line(self, expected, actual):
    "Return whether the regex EXPECTED matches the ACTUAL text."
    return re.match(expected, actual) is not None

  def display_differences(self, message, label, actual):
    display_lines(message, label, self.output, actual, True, False)

class UnorderedOutput(ExpectedOutput):
  """Marks unordered output, and performs comparisions."""

  def __cmp__(self, other):
    "Handle ValueError."
    try:
      return ExpectedOutput.__cmp__(self, other)
    except ValueError:
      return 1

  def is_equivalent_list(self, expected, actual):
    "Disregard the order of ACTUAL lines during comparison."
    if self.match_all:
      if len(expected) != len(actual):
        return False
      expected = list(expected)
      for actual_line in actual:
        try:
          i = self.is_equivalent_line(expected, actual_line)
          expected.pop(i)
        except ValueError:
          return False
      return True
    else:
      for actual_line in actual:
        try:
          self.is_equivalent_line(expected, actual_line)
          return True
        except ValueError:
          pass
      return False

  def is_equivalent_line(self, expected, actual):
    """Return the index into the EXPECTED lines of the line ACTUAL.
    Raise ValueError if not found."""
    return expected.index(actual)

  def display_differences(self, message, label, actual):
    display_lines(message, label, self.output, actual, False, True)

class UnorderedRegexOutput(UnorderedOutput, RegexOutput):
  def is_equivalent_line(self, expected, actual):
    for i in range(0, len(expected)):
      if RegexOutput.is_equivalent_line(self, expected[i], actual):
        return i
      else:
        raise ValueError("'%s' not found" % actual)

  def display_differences(self, message, label, actual):
    display_lines(message, label, self.output, actual, True, True)


######################################################################
# Displaying expected and actual output

def display_trees(message, label, expected, actual):
  'Print two trees, expected and actual.'
  if message is not None:
    print message
  if expected is not None:
    print 'EXPECTED', label + ':'
    tree.dump_tree(expected)
  if actual is not None:
    print 'ACTUAL', label + ':'
    tree.dump_tree(actual)


def display_lines(message, label, expected, actual, expected_is_regexp=None,
                  expected_is_unordered=None):
  """Print MESSAGE, unless it is None, then print EXPECTED (labeled
  with LABEL) followed by ACTUAL (also labeled with LABEL).
  Both EXPECTED and ACTUAL may be strings or lists of strings."""
  if message is not None:
    print message
  if expected is not None:
    output = 'EXPECTED %s' % label
    if expected_is_regexp:
      output += ' (regexp)'
    if expected_is_unordered:
      output += ' (unordered)'
    output += ':'
    print output
    map(sys.stdout.write, expected)
    if expected_is_regexp:
      map(sys.stdout.write, '\n')
  if actual is not None:
    print 'ACTUAL %s:' % label
    map(sys.stdout.write, actual)

def compare_and_display_lines(message, label, expected, actual,
                              raisable=main.SVNLineUnequal):
  """Compare two sets of output lines, and print them if they differ.
  MESSAGE is ignored if None.  EXPECTED may be an instance of
  ExpectedOutput (and if not, it is wrapped as such).  RAISABLE is an
  exception class, an instance of which is thrown if ACTUAL doesn't
  match EXPECTED."""
  ### It'd be nicer to use createExpectedOutput() here, but its
  ### semantics don't match all current consumers of this function.
  if not isinstance(expected, ExpectedOutput):
    expected = ExpectedOutput(expected)

  if expected != actual:
    expected.display_differences(message, label, actual)
    raise raisable

def verify_outputs(message, actual_stdout, actual_stderr,
                   expected_stdout, expected_stderr):
  """Compare and display expected vs. actual stderr and stdout lines,
  raising an exception if outputs don't match."""
  expected_stderr = createExpectedOutput(expected_stderr)
  expected_stdout = createExpectedOutput(expected_stdout)

  for (actual, expected, label, raisable) in (
      (actual_stderr, expected_stderr, 'STDERR', SVNExpectedStderr),
      (actual_stdout, expected_stdout, 'STDOUT', SVNExpectedStdout)):
    if expected is None:
      continue

    expected = createExpectedOutput(expected)
    if isinstance(expected, RegexOutput):
      raisable = main.SVNUnmatchedError
    elif not isinstance(expected, AnyOutput):
      raisable = main.SVNLineUnequal

    compare_and_display_lines(message, label, expected, actual, raisable)