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# IVLE - Informatics Virtual Learning Environment
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# Copyright (C) 2007-2008 The University of Melbourne
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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# Module: TestFilespace
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# Author: Dilshan Angampitiya
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# Steven Bird (revisions)
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# David Coles (revisions and moved to module)
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Our dummy file system which is accessed by code being tested.
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Implemented as a dictionary which maps filenames to strings
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def __init__(self, files=None):
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"Initialise, optionally with filename-filedata pairs"
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# dict mapping files to strings
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self._files.update(files)
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self._modified_files = set([])
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# dict mapping files to stringIO objects
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def add_file(self, filename, data):
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" Add a file to the filespace "
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self._files[filename] = data
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def openfile(self, filename, mode='r'):
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""" Open a file from the filespace with the given mode.
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Return a StringIO subclass object with the file contents.
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# currently very messy, needs to be cleaned up
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# Probably most of this should be in the initialiser to the TestStringIO
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if filename in self._open_files:
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raise IOError("File already open: %s" %filename)
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if not re.compile("[rwa][+b]{0,2}").match(mode):
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raise IOError("invalid mode %s" %mode)
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## TODO: validate filename?
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# initialise the file properly (truncate/create if required)
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self._files[filename] = ''
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self._modified_files.add(filename)
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elif filename not in self._files:
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self._files[filename] = ''
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self._modified_files.add(filename)
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raise IOError(2, "Access to file denied: %s" %filename)
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# for append mode, remember the existing data
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existing_data = self._files[filename]
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# determine what operations are allowed
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reading_ok = (len(mode) == 2 or mode[0] == 'r')
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writing_ok = (len(mode) == 2 or mode[0] in 'wa')
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# for all writing modes, start off with blank file
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initial_data = self._files[filename]
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file_object = TestStringIO(initial_data, filename, self, reading_ok, writing_ok, existing_data)
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self._open_files[filename] = file_object
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""" Flush all open files
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for file_object in self._open_files.values():
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def updatefile(self,filename, data):
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""" Callback function used by an open file to inform when it has been updated.
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if filename in self._open_files:
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self._files[filename] = data
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if self._open_files[filename].is_modified():
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self._modified_files.add(filename)
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raise IOError(2, "Access to file denied: %s" %filename)
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def closefile(self, filename):
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""" Callback function used by an open file to inform when it has been closed.
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if filename in self._open_files:
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del self._open_files[filename]
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def get_modified_files(self):
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"""" A subset of the filespace containing only those files which have been
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for filename in self._modified_files:
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modified_files[filename] = self._files[filename]
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return modified_files
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def get_open_files(self):
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" Return the names of all open files "
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return self._open_files.keys()
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""" Return a copy of the current filespace.
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Only the files are copied, not the modified or open file lists.
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return TestFilespace(self._files)
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class TestStringIO(StringIO.StringIO):
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A subclass of StringIO which acts as a file in our dummy file system
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def __init__(self, string, filename, filespace, reading_ok, writing_ok, existing_data):
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""" Initialise with the filedata, file name and infomation on what ops are
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StringIO.StringIO.__init__(self, string)
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self._filename = filename
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self._filespace = filespace
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self._reading_ok = reading_ok
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self._writing_ok = writing_ok
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self._existing_data = existing_data
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self._modified = False
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# Override all standard file ops. Make sure that they are valid with the given
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# permissions and if so then call the corresponding method in StringIO
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def read(self, *args):
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if not self._reading_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.read(self, *args)
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def readline(self, *args):
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if not self._reading_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.readline(self, *args)
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def readlines(self, *args):
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if not self._reading_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.readlines(self, *args)
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def seek(self, *args):
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if not self._reading_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.seek(self, *args)
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def truncate(self, *args):
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self._modified = True
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if not self._writing_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.truncate(self, *args)
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def write(self, *args):
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self._modified = True
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if not self._writing_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.write(self, *args)
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def writelines(self, *args):
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self._modified = True
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if not self._writing_ok:
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raise IOError(9, "Bad file descriptor")
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return StringIO.StringIO.writelines(self, *args)
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def is_modified(self):
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" Return true if the file has been written to, or truncated"
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return self._modified
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" Update the contents of the filespace with the new data "
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self._filespace.updatefile(self._filename, self._existing_data+self.getvalue())
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return StringIO.StringIO.flush(self)
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" Flush the file and close it "
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self._filespace.closefile(self._filename)
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return StringIO.StringIO.close(self)
added
removed
ivle/testfilespace.py
