Add python coverage module to third_party

third_party/pycoverage/coverage/codeunit.py

+"""Code unit (module) handling for Coverage."""
+
+import glob, os
+
+from coverage.backward import open_source, string_class, StringIO
+from coverage.misc import CoverageException
+
+
+def code_unit_factory(morfs, file_locator):
+    """Construct a list of CodeUnits from polymorphic inputs.
+
+    `morfs` is a module or a filename, or a list of same.
+
+    `file_locator` is a FileLocator that can help resolve filenames.
+
+    Returns a list of CodeUnit objects.
+
+    """
+    # Be sure we have a list.
+    if not isinstance(morfs, (list, tuple)):
+        morfs = [morfs]
+
+    # On Windows, the shell doesn't expand wildcards.  Do it here.
+    globbed = []
+    for morf in morfs:
+        if isinstance(morf, string_class) and ('?' in morf or '*' in morf):
+            globbed.extend(glob.glob(morf))
+        else:
+            globbed.append(morf)
+    morfs = globbed
+
+    code_units = [CodeUnit(morf, file_locator) for morf in morfs]
+
+    return code_units
+
+
+class CodeUnit(object):
+    """Code unit: a filename or module.
+
+    Instance attributes:
+
+    `name` is a human-readable name for this code unit.
+    `filename` is the os path from which we can read the source.
+    `relative` is a boolean.
+
+    """
+    def __init__(self, morf, file_locator):
+        self.file_locator = file_locator
+
+        if hasattr(morf, '__file__'):
+            f = morf.__file__
+        else:
+            f = morf
+        # .pyc files should always refer to a .py instead.
+        if f.endswith('.pyc') or f.endswith('.pyo'):
+            f = f[:-1]
+        elif f.endswith('$py.class'): # Jython
+            f = f[:-9] + ".py"
+        self.filename = self.file_locator.canonical_filename(f)
+
+        if hasattr(morf, '__name__'):
+            n = modname = morf.__name__
+            self.relative = True
+        else:
+            n = os.path.splitext(morf)[0]
+            rel = self.file_locator.relative_filename(n)
+            if os.path.isabs(n):
+                self.relative = (rel != n)
+            else:
+                self.relative = True
+            n = rel
+            modname = None
+        self.name = n
+        self.modname = modname
+
+    def __repr__(self):
+        return "<CodeUnit name=%r filename=%r>" % (self.name, self.filename)
+
+    # Annoying comparison operators. Py3k wants __lt__ etc, and Py2k needs all
+    # of them defined.
+
+    def __lt__(self, other):
+        return self.name < other.name
+    def __le__(self, other):
+        return self.name <= other.name
+    def __eq__(self, other):
+        return self.name == other.name
+    def __ne__(self, other):
+        return self.name != other.name
+    def __gt__(self, other):
+        return self.name > other.name
+    def __ge__(self, other):
+        return self.name >= other.name
+
+    def flat_rootname(self):
+        """A base for a flat filename to correspond to this code unit.
+
+        Useful for writing files about the code where you want all the files in
+        the same directory, but need to differentiate same-named files from
+        different directories.
+
+        For example, the file a/b/c.py might return 'a_b_c'
+
+        """
+        if self.modname:
+            return self.modname.replace('.', '_')
+        else:
+            root = os.path.splitdrive(self.name)[1]
+            return root.replace('\\', '_').replace('/', '_').replace('.', '_')
+
+    def source_file(self):
+        """Return an open file for reading the source of the code unit."""
+        if os.path.exists(self.filename):
+            # A regular text file: open it.
+            return open_source(self.filename)
+
+        # Maybe it's in a zip file?
+        source = self.file_locator.get_zip_data(self.filename)
+        if source is not None:
+            return StringIO(source)
+
+        # Couldn't find source.
+        raise CoverageException(
+            "No source for code '%s'." % self.filename
+            )
+
+    def should_be_python(self):
+        """Does it seem like this file should contain Python?
+
+        This is used to decide if a file reported as part of the exection of
+        a program was really likely to have contained Python in the first
+        place.
+
+        """
+        # Get the file extension.
+        _, ext = os.path.splitext(self.filename)
+
+        # Anything named *.py* should be Python.
+        if ext.startswith('.py'):
+            return True
+        # A file with no extension should be Python.
+        if not ext:
+            return True
+        # Everything else is probably not Python.
+        return False