Method expect

pexpect/spawnbase.py:254–355

This seeks through the stream until a pattern is matched. The pattern is overloaded and may take several types. The pattern can be a StringType, EOF, a compiled re, or a list of any of those types. Strings will be compiled to re types. This returns the index into the

(self, pattern, timeout=-1, searchwindowsize=-1, async_=False, **kw)

        return compiled_pattern_list

    def expect(self, pattern, timeout=-1, searchwindowsize=-1, async_=False, **kw):
        '''This seeks through the stream until a pattern is matched. The
        pattern is overloaded and may take several types. The pattern can be a
        StringType, EOF, a compiled re, or a list of any of those types.
        Strings will be compiled to re types. This returns the index into the
        pattern list. If the pattern was not a list this returns index 0 on a
        successful match. This may raise exceptions for EOF or TIMEOUT. To
        avoid the EOF or TIMEOUT exceptions add EOF or TIMEOUT to the pattern
        list. That will cause expect to match an EOF or TIMEOUT condition
        instead of raising an exception.

        If you pass a list of patterns and more than one matches, the first
        match in the stream is chosen. If more than one pattern matches at that
        point, the leftmost in the pattern list is chosen. For example::

            # the input is 'foobar'
            index = p.expect(['bar', 'foo', 'foobar'])
            # returns 1('foo') even though 'foobar' is a "better" match

        Please note, however, that buffering can affect this behavior, since
        input arrives in unpredictable chunks. For example::

            # the input is 'foobar'
            index = p.expect(['foobar', 'foo'])
            # returns 0('foobar') if all input is available at once,
            # but returns 1('foo') if parts of the final 'bar' arrive late

        When a match is found for the given pattern, the class instance
        attribute *match* becomes an re.MatchObject result.  Should an EOF
        or TIMEOUT pattern match, then the match attribute will be an instance
        of that exception class.  The pairing before and after class
        instance attributes are views of the data preceding and following
        the matching pattern.  On general exception, class attribute
        *before* is all data received up to the exception, while *match* and
        *after* attributes are value None.

        When the keyword argument timeout is -1 (default), then TIMEOUT will
        raise after the default value specified by the class timeout
        attribute. When None, TIMEOUT will not be raised and may block
        indefinitely until match.

        When the keyword argument searchwindowsize is -1 (default), then the
        value specified by the class maxread attribute is used.

        A list entry may be EOF or TIMEOUT instead of a string. This will
        catch these exceptions and return the index of the list entry instead
        of raising the exception. The attribute 'after' will be set to the
        exception type. The attribute 'match' will be None. This allows you to
        write code like this::

                index = p.expect(['good', 'bad', pexpect.EOF, pexpect.TIMEOUT])
                if index == 0:
                    do_something()
                elif index == 1:
                    do_something_else()
                elif index == 2:
                    do_some_other_thing()
                elif index == 3: