changeset 2066:a5d072f38a4a

add coverage.py module to tests directory.
written by ned batchelder and gareth rees.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/coverage.py	Thu Apr 13 15:10:03 2006 -0700
@@ -0,0 +1,891 @@
+#!/usr/bin/python
+#
+#             Perforce Defect Tracking Integration Project
+#              <http://www.ravenbrook.com/project/p4dti/>
+#
+#                   COVERAGE.PY -- COVERAGE TESTING
+#
+#             Gareth Rees, Ravenbrook Limited, 2001-12-04
+#                     Ned Batchelder, 2004-12-12
+#         http://nedbatchelder.com/code/modules/coverage.html
+#
+#
+# 1. INTRODUCTION
+#
+# This module provides coverage testing for Python code.
+#
+# The intended readership is all Python developers.
+#
+# This document is not confidential.
+#
+# See [GDR 2001-12-04a] for the command-line interface, programmatic
+# interface and limitations.  See [GDR 2001-12-04b] for requirements and
+# design.
+
+"""Usage:
+
+coverage.py -x MODULE.py [ARG1 ARG2 ...]
+    Execute module, passing the given command-line arguments, collecting
+    coverage data.
+
+coverage.py -e
+    Erase collected coverage data.
+
+coverage.py -r [-m] [-o dir1,dir2,...] FILE1 FILE2 ...
+    Report on the statement coverage for the given files.  With the -m
+    option, show line numbers of the statements that weren't executed.
+
+coverage.py -a [-d dir] [-o dir1,dir2,...] FILE1 FILE2 ...
+    Make annotated copies of the given files, marking statements that
+    are executed with > and statements that are missed with !.  With
+    the -d option, make the copies in that directory.  Without the -d
+    option, make each copy in the same directory as the original.
+
+-o dir,dir2,...
+  Omit reporting or annotating files when their filename path starts with
+  a directory listed in the omit list.
+  e.g. python coverage.py -i -r -o c:\python23,lib\enthought\traits
+
+Coverage data is saved in the file .coverage by default.  Set the
+COVERAGE_FILE environment variable to save it somewhere else."""
+
+__version__ = "2.5.20051204"    # see detailed history at the end of this file.
+
+import compiler
+import compiler.visitor
+import os
+import re
+import string
+import sys
+import threading
+import types
+
+# 2. IMPLEMENTATION
+#
+# This uses the "singleton" pattern.
+#
+# The word "morf" means a module object (from which the source file can
+# be deduced by suitable manipulation of the __file__ attribute) or a
+# filename.
+#
+# When we generate a coverage report we have to canonicalize every
+# filename in the coverage dictionary just in case it refers to the
+# module we are reporting on.  It seems a shame to throw away this
+# information so the data in the coverage dictionary is transferred to
+# the 'cexecuted' dictionary under the canonical filenames.
+#
+# The coverage dictionary is called "c" and the trace function "t".  The
+# reason for these short names is that Python looks up variables by name
+# at runtime and so execution time depends on the length of variables!
+# In the bottleneck of this application it's appropriate to abbreviate
+# names to increase speed.
+
+class StatementFindingAstVisitor(compiler.visitor.ASTVisitor):
+    def __init__(self, statements, excluded, suite_spots):
+        compiler.visitor.ASTVisitor.__init__(self)
+        self.statements = statements
+        self.excluded = excluded
+        self.suite_spots = suite_spots
+        self.excluding_suite = 0
+        
+    def doRecursive(self, node):
+        self.recordNodeLine(node)
+        for n in node.getChildNodes():
+            self.dispatch(n)
+
+    visitStmt = visitModule = doRecursive
+    
+    def doCode(self, node):
+        if hasattr(node, 'decorators') and node.decorators:
+            self.dispatch(node.decorators)
+        self.doSuite(node, node.code)
+    
+    visitFunction = visitClass = doCode
+
+    def getFirstLine(self, node):
+        # Find the first line in the tree node.
+        lineno = node.lineno
+        for n in node.getChildNodes():
+            f = self.getFirstLine(n)
+            if lineno and f:
+                lineno = min(lineno, f)
+            else:
+                lineno = lineno or f
+        return lineno
+
+    def getLastLine(self, node):
+        # Find the first line in the tree node.
+        lineno = node.lineno
+        for n in node.getChildNodes():
+            lineno = max(lineno, self.getLastLine(n))
+        return lineno
+    
+    def doStatement(self, node):
+        self.recordLine(self.getFirstLine(node))
+
+    visitAssert = visitAssign = visitAssTuple = visitDiscard = visitPrint = \
+        visitPrintnl = visitRaise = visitSubscript = visitDecorators = \
+        doStatement
+    
+    def recordNodeLine(self, node):
+        return self.recordLine(node.lineno)
+    
+    def recordLine(self, lineno):
+        # Returns a bool, whether the line is included or excluded.
+        if lineno:
+            # Multi-line tests introducing suites have to get charged to their
+            # keyword.
+            if lineno in self.suite_spots:
+                lineno = self.suite_spots[lineno][0]
+            # If we're inside an exluded suite, record that this line was
+            # excluded.
+            if self.excluding_suite:
+                self.excluded[lineno] = 1
+                return 0
+            # If this line is excluded, or suite_spots maps this line to
+            # another line that is exlcuded, then we're excluded.
+            elif self.excluded.has_key(lineno) or \
+                 self.suite_spots.has_key(lineno) and \
+                 self.excluded.has_key(self.suite_spots[lineno][1]):
+                return 0
+            # Otherwise, this is an executable line.
+            else:
+                self.statements[lineno] = 1
+                return 1
+        return 0
+    
+    default = recordNodeLine
+    
+    def recordAndDispatch(self, node):
+        self.recordNodeLine(node)
+        self.dispatch(node)
+
+    def doSuite(self, intro, body, exclude=0):
+        exsuite = self.excluding_suite
+        if exclude or (intro and not self.recordNodeLine(intro)):
+            self.excluding_suite = 1
+        self.recordAndDispatch(body)
+        self.excluding_suite = exsuite
+        
+    def doPlainWordSuite(self, prevsuite, suite):
+        # Finding the exclude lines for else's is tricky, because they aren't
+        # present in the compiler parse tree.  Look at the previous suite,
+        # and find its last line.  If any line between there and the else's
+        # first line are excluded, then we exclude the else.
+        lastprev = self.getLastLine(prevsuite)
+        firstelse = self.getFirstLine(suite)
+        for l in range(lastprev+1, firstelse):
+            if self.suite_spots.has_key(l):
+                self.doSuite(None, suite, exclude=self.excluded.has_key(l))
+                break
+        else:
+            self.doSuite(None, suite)
+        
+    def doElse(self, prevsuite, node):
+        if node.else_:
+            self.doPlainWordSuite(prevsuite, node.else_)
+    
+    def visitFor(self, node):
+        self.doSuite(node, node.body)
+        self.doElse(node.body, node)
+
+    def visitIf(self, node):
+        # The first test has to be handled separately from the rest.
+        # The first test is credited to the line with the "if", but the others
+        # are credited to the line with the test for the elif.
+        self.doSuite(node, node.tests[0][1])
+        for t, n in node.tests[1:]:
+            self.doSuite(t, n)
+        self.doElse(node.tests[-1][1], node)
+
+    def visitWhile(self, node):
+        self.doSuite(node, node.body)
+        self.doElse(node.body, node)
+
+    def visitTryExcept(self, node):
+        self.doSuite(node, node.body)
+        for i in range(len(node.handlers)):
+            a, b, h = node.handlers[i]
+            if not a:
+                # It's a plain "except:".  Find the previous suite.
+                if i > 0:
+                    prev = node.handlers[i-1][2]
+                else:
+                    prev = node.body
+                self.doPlainWordSuite(prev, h)
+            else:
+                self.doSuite(a, h)
+        self.doElse(node.handlers[-1][2], node)
+    
+    def visitTryFinally(self, node):
+        self.doSuite(node, node.body)
+        self.doPlainWordSuite(node.body, node.final)
+        
+    def visitGlobal(self, node):
+        # "global" statements don't execute like others (they don't call the
+        # trace function), so don't record their line numbers.
+        pass
+
+the_coverage = None
+
+class coverage:
+    error = "coverage error"
+
+    # Name of the cache file (unless environment variable is set).
+    cache_default = ".coverage"
+
+    # Environment variable naming the cache file.
+    cache_env = "COVERAGE_FILE"
+
+    # A dictionary with an entry for (Python source file name, line number
+    # in that file) if that line has been executed.
+    c = {}
+    
+    # A map from canonical Python source file name to a dictionary in
+    # which there's an entry for each line number that has been
+    # executed.
+    cexecuted = {}
+
+    # Cache of results of calling the analysis2() method, so that you can
+    # specify both -r and -a without doing double work.
+    analysis_cache = {}
+
+    # Cache of results of calling the canonical_filename() method, to
+    # avoid duplicating work.
+    canonical_filename_cache = {}
+
+    def __init__(self):
+        global the_coverage
+        if the_coverage:
+            raise self.error, "Only one coverage object allowed."
+        self.usecache = 1
+        self.cache = None
+        self.exclude_re = ''
+        self.nesting = 0
+        self.cstack = []
+        self.xstack = []
+        self.relative_dir = os.path.normcase(os.path.abspath(os.curdir)+os.path.sep)
+
+    # t(f, x, y).  This method is passed to sys.settrace as a trace function.  
+    # See [van Rossum 2001-07-20b, 9.2] for an explanation of sys.settrace and 
+    # the arguments and return value of the trace function.
+    # See [van Rossum 2001-07-20a, 3.2] for a description of frame and code
+    # objects.
+    
+    def t(self, f, w, a):                                   #pragma: no cover
+        #print w, f.f_code.co_filename, f.f_lineno
+        if w == 'line':
+            self.c[(f.f_code.co_filename, f.f_lineno)] = 1
+            for c in self.cstack:
+                c[(f.f_code.co_filename, f.f_lineno)] = 1
+        return self.t
+    
+    def help(self, error=None):
+        if error:
+            print error
+            print
+        print __doc__
+        sys.exit(1)
+
+    def command_line(self):
+        import getopt
+        settings = {}
+        optmap = {
+            '-a': 'annotate',
+            '-d:': 'directory=',
+            '-e': 'erase',
+            '-h': 'help',
+            '-i': 'ignore-errors',
+            '-m': 'show-missing',
+            '-r': 'report',
+            '-x': 'execute',
+            '-o': 'omit=',
+            }
+        short_opts = string.join(map(lambda o: o[1:], optmap.keys()), '')
+        long_opts = optmap.values()
+        options, args = getopt.getopt(sys.argv[1:], short_opts, long_opts)
+        for o, a in options:
+            if optmap.has_key(o):
+                settings[optmap[o]] = 1
+            elif optmap.has_key(o + ':'):
+                settings[optmap[o + ':']] = a
+            elif o[2:] in long_opts:
+                settings[o[2:]] = 1
+            elif o[2:] + '=' in long_opts:
+                settings[o[2:]] = a
+            else:
+                self.help("Unknown option: '%s'." % o)
+        if settings.get('help'):
+            self.help()
+        for i in ['erase', 'execute']:
+            for j in ['annotate', 'report']:
+                if settings.get(i) and settings.get(j):
+                    self.help("You can't specify the '%s' and '%s' "
+                              "options at the same time." % (i, j))
+        args_needed = (settings.get('execute')
+                       or settings.get('annotate')
+                       or settings.get('report'))
+        action = settings.get('erase') or args_needed
+        if not action:
+            self.help("You must specify at least one of -e, -x, -r, or -a.")
+        if not args_needed and args:
+            self.help("Unexpected arguments %s." % args)
+        
+        self.get_ready()
+        self.exclude('#pragma[: ]+[nN][oO] [cC][oO][vV][eE][rR]')
+
+        if settings.get('erase'):
+            self.erase()
+        if settings.get('execute'):
+            if not args:
+                self.help("Nothing to do.")
+            sys.argv = args
+            self.start()
+            import __main__
+            sys.path[0] = os.path.dirname(sys.argv[0])
+            execfile(sys.argv[0], __main__.__dict__)
+        if not args:
+            args = self.cexecuted.keys()
+        ignore_errors = settings.get('ignore-errors')
+        show_missing = settings.get('show-missing')
+        directory = settings.get('directory=')
+        omit = settings.get('omit=')
+        if omit is not None:
+            omit = omit.split(',')
+        else:
+            omit = []
+
+        if settings.get('report'):
+            self.report(args, show_missing, ignore_errors, omit_prefixes=omit)
+        if settings.get('annotate'):
+            self.annotate(args, directory, ignore_errors, omit_prefixes=omit)
+
+    def use_cache(self, usecache):
+        self.usecache = usecache
+        
+    def get_ready(self):
+        if self.usecache and not self.cache:
+            self.cache = os.environ.get(self.cache_env, self.cache_default)
+            self.restore()
+        self.analysis_cache = {}
+        
+    def start(self):
+        self.get_ready()
+        if self.nesting == 0:                               #pragma: no cover
+            sys.settrace(self.t)
+            if hasattr(threading, 'settrace'):
+                threading.settrace(self.t)
+        self.nesting += 1
+        
+    def stop(self):
+        self.nesting -= 1
+        if self.nesting == 0:                               #pragma: no cover
+            sys.settrace(None)
+            if hasattr(threading, 'settrace'):
+                threading.settrace(None)
+
+    def erase(self):
+        self.c = {}
+        self.analysis_cache = {}
+        self.cexecuted = {}
+        if self.cache and os.path.exists(self.cache):
+            os.remove(self.cache)
+        self.exclude_re = ""
+
+    def exclude(self, re):
+        if self.exclude_re:
+            self.exclude_re += "|"
+        self.exclude_re += "(" + re + ")"
+
+    def begin_recursive(self):
+        self.cstack.append(self.c)
+        self.xstack.append(self.exclude_re)
+        
+    def end_recursive(self):
+        self.c = self.cstack.pop()
+        self.exclude_re = self.xstack.pop()
+
+    # save().  Save coverage data to the coverage cache.
+
+    def save(self):
+        if self.usecache and self.cache:
+            self.canonicalize_filenames()
+            cache = open(self.cache, 'wb')
+            import marshal
+            marshal.dump(self.cexecuted, cache)
+            cache.close()
+
+    # restore().  Restore coverage data from the coverage cache (if it exists).
+
+    def restore(self):
+        self.c = {}
+        self.cexecuted = {}
+        assert self.usecache
+        if not os.path.exists(self.cache):
+            return
+        try:
+            cache = open(self.cache, 'rb')
+            import marshal
+            cexecuted = marshal.load(cache)
+            cache.close()
+            if isinstance(cexecuted, types.DictType):
+                self.cexecuted = cexecuted
+        except:
+            pass
+
+    # canonical_filename(filename).  Return a canonical filename for the
+    # file (that is, an absolute path with no redundant components and
+    # normalized case).  See [GDR 2001-12-04b, 3.3].
+
+    def canonical_filename(self, filename):
+        if not self.canonical_filename_cache.has_key(filename):
+            f = filename
+            if os.path.isabs(f) and not os.path.exists(f):
+                f = os.path.basename(f)
+            if not os.path.isabs(f):
+                for path in [os.curdir] + sys.path:
+                    g = os.path.join(path, f)
+                    if os.path.exists(g):
+                        f = g
+                        break
+            cf = os.path.normcase(os.path.abspath(f))
+            self.canonical_filename_cache[filename] = cf
+        return self.canonical_filename_cache[filename]
+
+    # canonicalize_filenames().  Copy results from "c" to "cexecuted", 
+    # canonicalizing filenames on the way.  Clear the "c" map.
+
+    def canonicalize_filenames(self):
+        for filename, lineno in self.c.keys():
+            f = self.canonical_filename(filename)
+            if not self.cexecuted.has_key(f):
+                self.cexecuted[f] = {}
+            self.cexecuted[f][lineno] = 1
+        self.c = {}
+
+    # morf_filename(morf).  Return the filename for a module or file.
+
+    def morf_filename(self, morf):
+        if isinstance(morf, types.ModuleType):
+            if not hasattr(morf, '__file__'):
+                raise self.error, "Module has no __file__ attribute."
+            file = morf.__file__
+        else:
+            file = morf
+        return self.canonical_filename(file)
+
+    # analyze_morf(morf).  Analyze the module or filename passed as
+    # the argument.  If the source code can't be found, raise an error.
+    # Otherwise, return a tuple of (1) the canonical filename of the
+    # source code for the module, (2) a list of lines of statements
+    # in the source code, and (3) a list of lines of excluded statements.
+
+    def analyze_morf(self, morf):
+        if self.analysis_cache.has_key(morf):
+            return self.analysis_cache[morf]
+        filename = self.morf_filename(morf)
+        ext = os.path.splitext(filename)[1]
+        if ext == '.pyc':
+            if not os.path.exists(filename[0:-1]):
+                raise self.error, ("No source for compiled code '%s'."
+                                   % filename)
+            filename = filename[0:-1]
+        elif ext != '.py':
+            raise self.error, "File '%s' not Python source." % filename
+        source = open(filename, 'r')
+        lines, excluded_lines = self.find_executable_statements(
+            source.read(), exclude=self.exclude_re
+            )
+        source.close()
+        result = filename, lines, excluded_lines
+        self.analysis_cache[morf] = result
+        return result
+
+    def get_suite_spots(self, tree, spots):
+        import symbol, token
+        for i in range(1, len(tree)):
+            if type(tree[i]) == type(()):
+                if tree[i][0] == symbol.suite:
+                    # Found a suite, look back for the colon and keyword.
+                    lineno_colon = lineno_word = None
+                    for j in range(i-1, 0, -1):
+                        if tree[j][0] == token.COLON:
+                            lineno_colon = tree[j][2]
+                        elif tree[j][0] == token.NAME:
+                            if tree[j][1] == 'elif':
+                                # Find the line number of the first non-terminal
+                                # after the keyword.
+                                t = tree[j+1]
+                                while t and token.ISNONTERMINAL(t[0]):
+                                    t = t[1]
+                                if t:
+                                    lineno_word = t[2]
+                            else:
+                                lineno_word = tree[j][2]
+                            break
+                        elif tree[j][0] == symbol.except_clause:
+                            # "except" clauses look like:
+                            # ('except_clause', ('NAME', 'except', lineno), ...)
+                            if tree[j][1][0] == token.NAME:
+                                lineno_word = tree[j][1][2]
+                                break
+                    if lineno_colon and lineno_word:
+                        # Found colon and keyword, mark all the lines
+                        # between the two with the two line numbers.
+                        for l in range(lineno_word, lineno_colon+1):
+                            spots[l] = (lineno_word, lineno_colon)
+                self.get_suite_spots(tree[i], spots)
+
+    def find_executable_statements(self, text, exclude=None):
+        # Find lines which match an exclusion pattern.
+        excluded = {}
+        suite_spots = {}
+        if exclude:
+            reExclude = re.compile(exclude)
+            lines = text.split('\n')
+            for i in range(len(lines)):
+                if reExclude.search(lines[i]):
+                    excluded[i+1] = 1
+
+        import parser
+        tree = parser.suite(text+'\n\n').totuple(1)
+        self.get_suite_spots(tree, suite_spots)
+            
+        # Use the compiler module to parse the text and find the executable
+        # statements.  We add newlines to be impervious to final partial lines.
+        statements = {}
+        ast = compiler.parse(text+'\n\n')
+        visitor = StatementFindingAstVisitor(statements, excluded, suite_spots)
+        compiler.walk(ast, visitor, walker=visitor)
+
+        lines = statements.keys()
+        lines.sort()
+        excluded_lines = excluded.keys()
+        excluded_lines.sort()
+        return lines, excluded_lines
+
+    # format_lines(statements, lines).  Format a list of line numbers
+    # for printing by coalescing groups of lines as long as the lines
+    # represent consecutive statements.  This will coalesce even if
+    # there are gaps between statements, so if statements =
+    # [1,2,3,4,5,10,11,12,13,14] and lines = [1,2,5,10,11,13,14] then
+    # format_lines will return "1-2, 5-11, 13-14".
+
+    def format_lines(self, statements, lines):
+        pairs = []
+        i = 0
+        j = 0
+        start = None
+        pairs = []
+        while i < len(statements) and j < len(lines):
+            if statements[i] == lines[j]:
+                if start == None:
+                    start = lines[j]
+                end = lines[j]
+                j = j + 1
+            elif start:
+                pairs.append((start, end))
+                start = None
+            i = i + 1
+        if start:
+            pairs.append((start, end))
+        def stringify(pair):
+            start, end = pair
+            if start == end:
+                return "%d" % start
+            else:
+                return "%d-%d" % (start, end)
+        return string.join(map(stringify, pairs), ", ")
+
+    # Backward compatibility with version 1.
+    def analysis(self, morf):
+        f, s, _, m, mf = self.analysis2(morf)
+        return f, s, m, mf
+
+    def analysis2(self, morf):
+        filename, statements, excluded = self.analyze_morf(morf)
+        self.canonicalize_filenames()
+        if not self.cexecuted.has_key(filename):
+            self.cexecuted[filename] = {}
+        missing = []
+        for line in statements:
+            if not self.cexecuted[filename].has_key(line):
+                missing.append(line)
+        return (filename, statements, excluded, missing,
+                self.format_lines(statements, missing))
+
+    def relative_filename(self, filename):
+        """ Convert filename to relative filename from self.relative_dir.
+        """
+        return filename.replace(self.relative_dir, "")
+
+    def morf_name(self, morf):
+        """ Return the name of morf as used in report.
+        """
+        if isinstance(morf, types.ModuleType):
+            return morf.__name__
+        else:
+            return self.relative_filename(os.path.splitext(morf)[0])
+
+    def filter_by_prefix(self, morfs, omit_prefixes):
+        """ Return list of morfs where the morf name does not begin
+            with any one of the omit_prefixes.
+        """
+        filtered_morfs = []
+        for morf in morfs:
+            for prefix in omit_prefixes:
+                if self.morf_name(morf).startswith(prefix):
+                    break
+            else:
+                filtered_morfs.append(morf)
+
+        return filtered_morfs
+
+    def morf_name_compare(self, x, y):
+        return cmp(self.morf_name(x), self.morf_name(y))
+
+    def report(self, morfs, show_missing=1, ignore_errors=0, file=None, omit_prefixes=[]):
+        if not isinstance(morfs, types.ListType):
+            morfs = [morfs]
+        morfs = self.filter_by_prefix(morfs, omit_prefixes)
+        morfs.sort(self.morf_name_compare)
+
+        max_name = max([5,] + map(len, map(self.morf_name, morfs)))
+        fmt_name = "%%- %ds  " % max_name
+        fmt_err = fmt_name + "%s: %s"
+        header = fmt_name % "Name" + " Stmts   Exec  Cover"
+        fmt_coverage = fmt_name + "% 6d % 6d % 5d%%"
+        if show_missing:
+            header = header + "   Missing"
+            fmt_coverage = fmt_coverage + "   %s"
+        if not file:
+            file = sys.stdout
+        print >>file, header
+        print >>file, "-" * len(header)
+        total_statements = 0
+        total_executed = 0
+        for morf in morfs:
+            name = self.morf_name(morf)
+            try:
+                _, statements, _, missing, readable  = self.analysis2(morf)
+                n = len(statements)
+                m = n - len(missing)
+                if n > 0:
+                    pc = 100.0 * m / n
+                else:
+                    pc = 100.0
+                args = (name, n, m, pc)
+                if show_missing:
+                    args = args + (readable,)
+                print >>file, fmt_coverage % args
+                total_statements = total_statements + n
+                total_executed = total_executed + m
+            except KeyboardInterrupt:                       #pragma: no cover
+                raise
+            except:
+                if not ignore_errors:
+                    type, msg = sys.exc_info()[0:2]
+                    print >>file, fmt_err % (name, type, msg)
+        if len(morfs) > 1:
+            print >>file, "-" * len(header)
+            if total_statements > 0:
+                pc = 100.0 * total_executed / total_statements
+            else:
+                pc = 100.0
+            args = ("TOTAL", total_statements, total_executed, pc)
+            if show_missing:
+                args = args + ("",)
+            print >>file, fmt_coverage % args
+
+    # annotate(morfs, ignore_errors).
+
+    blank_re = re.compile(r"\s*(#|$)")
+    else_re = re.compile(r"\s*else\s*:\s*(#|$)")
+
+    def annotate(self, morfs, directory=None, ignore_errors=0, omit_prefixes=[]):
+        morfs = self.filter_by_prefix(morfs, omit_prefixes)
+        for morf in morfs:
+            try:
+                filename, statements, excluded, missing, _ = self.analysis2(morf)
+                self.annotate_file(filename, statements, excluded, missing, directory)
+            except KeyboardInterrupt:
+                raise
+            except:
+                if not ignore_errors:
+                    raise
+                
+    def annotate_file(self, filename, statements, excluded, missing, directory=None):
+        source = open(filename, 'r')
+        if directory:
+            dest_file = os.path.join(directory,
+                                     os.path.basename(filename)
+                                     + ',cover')
+        else:
+            dest_file = filename + ',cover'
+        dest = open(dest_file, 'w')
+        lineno = 0
+        i = 0
+        j = 0
+        covered = 1
+        while 1:
+            line = source.readline()
+            if line == '':
+                break
+            lineno = lineno + 1
+            while i < len(statements) and statements[i] < lineno:
+                i = i + 1
+            while j < len(missing) and missing[j] < lineno:
+                j = j + 1
+            if i < len(statements) and statements[i] == lineno:
+                covered = j >= len(missing) or missing[j] > lineno
+            if self.blank_re.match(line):
+                dest.write('  ')
+            elif self.else_re.match(line):
+                # Special logic for lines containing only 'else:'.  
+                # See [GDR 2001-12-04b, 3.2].
+                if i >= len(statements) and j >= len(missing):
+                    dest.write('! ')
+                elif i >= len(statements) or j >= len(missing):
+                    dest.write('> ')
+                elif statements[i] == missing[j]:
+                    dest.write('! ')
+                else:
+                    dest.write('> ')
+            elif lineno in excluded:
+                dest.write('- ')
+            elif covered:
+                dest.write('> ')
+            else:
+                dest.write('! ')
+            dest.write(line)
+        source.close()
+        dest.close()
+
+# Singleton object.
+the_coverage = coverage()
+
+# Module functions call methods in the singleton object.
+def use_cache(*args, **kw): return the_coverage.use_cache(*args, **kw)
+def start(*args, **kw): return the_coverage.start(*args, **kw)
+def stop(*args, **kw): return the_coverage.stop(*args, **kw)
+def erase(*args, **kw): return the_coverage.erase(*args, **kw)
+def begin_recursive(*args, **kw): return the_coverage.begin_recursive(*args, **kw)
+def end_recursive(*args, **kw): return the_coverage.end_recursive(*args, **kw)
+def exclude(*args, **kw): return the_coverage.exclude(*args, **kw)
+def analysis(*args, **kw): return the_coverage.analysis(*args, **kw)
+def analysis2(*args, **kw): return the_coverage.analysis2(*args, **kw)
+def report(*args, **kw): return the_coverage.report(*args, **kw)
+def annotate(*args, **kw): return the_coverage.annotate(*args, **kw)
+def annotate_file(*args, **kw): return the_coverage.annotate_file(*args, **kw)
+
+# Save coverage data when Python exits.  (The atexit module wasn't
+# introduced until Python 2.0, so use sys.exitfunc when it's not
+# available.)
+try:
+    import atexit
+    atexit.register(the_coverage.save)
+except ImportError:
+    sys.exitfunc = the_coverage.save
+
+# Command-line interface.
+if __name__ == '__main__':
+    the_coverage.command_line()
+
+
+# A. REFERENCES
+#
+# [GDR 2001-12-04a] "Statement coverage for Python"; Gareth Rees;
+# Ravenbrook Limited; 2001-12-04;
+# <http://www.nedbatchelder.com/code/modules/rees-coverage.html>.
+#
+# [GDR 2001-12-04b] "Statement coverage for Python: design and
+# analysis"; Gareth Rees; Ravenbrook Limited; 2001-12-04;
+# <http://www.nedbatchelder.com/code/modules/rees-design.html>.
+#
+# [van Rossum 2001-07-20a] "Python Reference Manual (releae 2.1.1)";
+# Guide van Rossum; 2001-07-20;
+# <http://www.python.org/doc/2.1.1/ref/ref.html>.
+#
+# [van Rossum 2001-07-20b] "Python Library Reference"; Guido van Rossum;
+# 2001-07-20; <http://www.python.org/doc/2.1.1/lib/lib.html>.
+#
+#
+# B. DOCUMENT HISTORY
+#
+# 2001-12-04 GDR Created.
+#
+# 2001-12-06 GDR Added command-line interface and source code
+# annotation.
+#
+# 2001-12-09 GDR Moved design and interface to separate documents.
+#
+# 2001-12-10 GDR Open cache file as binary on Windows.  Allow
+# simultaneous -e and -x, or -a and -r.
+#
+# 2001-12-12 GDR Added command-line help.  Cache analysis so that it
+# only needs to be done once when you specify -a and -r.
+#
+# 2001-12-13 GDR Improved speed while recording.  Portable between
+# Python 1.5.2 and 2.1.1.
+#
+# 2002-01-03 GDR Module-level functions work correctly.
+#
+# 2002-01-07 GDR Update sys.path when running a file with the -x option,
+# so that it matches the value the program would get if it were run on
+# its own.
+#
+# 2004-12-12 NMB Significant code changes.
+# - Finding executable statements has been rewritten so that docstrings and
+#   other quirks of Python execution aren't mistakenly identified as missing
+#   lines.
+# - Lines can be excluded from consideration, even entire suites of lines.
+# - The filesystem cache of covered lines can be disabled programmatically.
+# - Modernized the code.
+#
+# 2004-12-14 NMB Minor tweaks.  Return 'analysis' to its original behavior
+# and add 'analysis2'.  Add a global for 'annotate', and factor it, adding
+# 'annotate_file'.
+#
+# 2004-12-31 NMB Allow for keyword arguments in the module global functions.
+# Thanks, Allen.
+#
+# 2005-12-02 NMB Call threading.settrace so that all threads are measured.
+# Thanks Martin Fuzzey. Add a file argument to report so that reports can be 
+# captured to a different destination.
+#
+# 2005-12-03 NMB coverage.py can now measure itself.
+#
+# 2005-12-04 NMB Adapted Greg Rogers' patch for using relative filenames,
+# and sorting and omitting files to report on.
+#
+# C. COPYRIGHT AND LICENCE
+#
+# Copyright 2001 Gareth Rees.  All rights reserved.
+# Copyright 2004-2005 Ned Batchelder.  All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the
+#    distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+# TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+# DAMAGE.
+#
+# $Id: coverage.py 26 2005-12-04 18:42:44Z ned $