coverage.py 文件源码

def analyze_morf(self, morf):
        if morf in self.analysis_cache:
            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')
        import parser
        tree = parser.suite(source.read()).totuple(1)
        source.close()
        statements = {}
        self.find_statements(tree, statements)
        lines = list(statements.keys())
        lines.sort()
        result = filename, lines
        self.analysis_cache[morf] = result
        return result

    # find_statements(tree, dict).  Find each statement in the parse
    # tree and record the line on which the statement starts in the
    # dictionary (by assigning it to 1).
    #
    # It works by walking the whole tree depth-first.  Every time it
    # comes across a statement (symbol.stmt -- this includes compound
    # statements like 'if' and 'while') it calls find_statement, which
    # descends the tree below the statement to find the first terminal
    # token in that statement and record the lines on which that token
    # was found.
    #
    # This algorithm may find some lines several times (because of the
    # grammar production statement -> compound statement -> statement),
    # but that doesn't matter because we record lines as the keys of the
    # dictionary.
    #
    # See also [GDR 2001-12-04b, 3.2].