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Why is sage behaving weird when rounding rational numbers?

I might be doing something stupid, but Sage's int() and round() functions seem to be buggy to me.

I'm trying to use these with rational numbers to round towards zero. I'd expect -7/4 to round to -1 and +7/4 to round to 1. Instead I get different behavior for rationals and their decimal representation:

│ SageMath Version 7.1, Release Date: 2016-03-20                     │
│ Type "notebook()" for the browser-based notebook interface.        │
│ Type "help()" for help.                                            │
sage: int(-1.75)              # Correctly rounds towards zero
sage: int(-7/4)               # Does not round towards zero
sage: (-7/4).round("toward")  # Does not round towards zero (despite what the documentation claims!)
sage: -7/4 + 0.0              # The numbers are in fact the same!

How do I round rational numbers towards zero in Sage?