execute & mogrify don't fail with no format placeholder but with arguments given

Hi,

I realized that cursor.{execute,mogrify} do accept not-empty arguments (either dict or tuple) while the query string has no format placeholder :

>>> sys.version
'3.3.1 (default, Sep 25 2013, 19:29:01) \n[GCC 4.7.3]'

>>> psycopg2.__version__
'2.5.1 (dt dec pq3 ext)'

>>> conn = psycopg2.connect(database='greg')
>>> cursor = conn.cursor()

Problem 1:

>>> cursor.execute('SELECT 1', dict(a=1, b=2) )
>>> cursor.mogrify('SELECT 1', dict(a=1, b=2) )
b'SELECT 1'

>>> cursor.execute('SELECT 1', (1,2) )
>>> cursor.mogrify('SELECT 1', (1,2) )
b'SELECT 1'
>>>

I'm not sure if this is a bug or a feature.
I would say the first one when compared with this :

1) too many (un-named) arguments given:

>>> cursor.mogrify('SELECT %s', (1,2) )
Traceback (most recent call last):
  File "<pyshell#215>", line 1, in <module>
    cursor.mogrify('SELECT %s', (1,2) )
TypeError: not all arguments converted during string formatting
>>>

2) or not enough arguments given:

>>> cursor.mogrify('SELECT %s, %s', (1,))
Traceback (most recent call last):
  File "<pyshell#217>", line 1, in <module>
    cursor.mogrify('SELECT %s, %s', (1,))
IndexError: tuple index out of range
>>>

or the same with dict argument:

>>> cursor.mogrify('SELECT %(a)s, %(b)s', dict(a=1))
Traceback (most recent call last):
  File "<pyshell#218>", line 1, in <module>
    cursor.mogrify('SELECT %(a)s, %(b)s', dict(a=1))
KeyError: 'b'
>>>

IMHO: The only "valid" & "special" case is with the use of a query with named arguments and a dict where there are more keys than in the query :

>>> cursor.mogrify('SELECT %(a)s', dict(a=1, b=1))
b'SELECT 1'
>>>

Now there is a last special case : query with (named or not) arguments but with no (or None) argument :

Problem 2:

>>> cursor.mogrify('SELECT %(a)s')
b'SELECT %(a)s'
>>> cursor.mogrify('SELECT %s')
b'SELECT %s'
>>>

where I would also have expected a TypeError because afaik such query will inevitably fail if executed.

wdyt of such thoughts ?

would it be correct to so declare the 2 problems (1 & 2, probably related) as bugs ?

as far as I know problem 2 will always trigger a database error so it should'nt be a problem to make it raise a TypeError.
But I can see the problem with making a typeerror on problem-1 there could have some people which are using this form of query.. then maybe in a multi-steps way : first put a warning then on some later release change it to a typeerror ?

regards,