Continued Fraction of a Rational Number
Ruby, 45 43 46 bytes

f=-&gt;n{x,y=n.to_r.divmod 1;[x,*y==0?[]:f[1/y]]}


Accepts input as a string.

All test cases pass:

llama@llama:~$ for n in 860438 3.245 -4.2 -114.7802 0/11 1/42 2/7 -18/17056 -17056/18; do ruby -e 'f=-&gt;n{x,y=n.to_r.divmod 1;[x,*y==0?[]:f[1/y]]}; p f["'$n'"]'; done
[860438]
[3, 4, 12, 4]
[-5, 1, 4]
[-115, 4, 1, 1, 4, 1, 1, 5, 1, 1, 4]
[0]
[0, 42]
[0, 3, 2]
[-1, 1, 946, 1, 1, 4]
[-948, 2, 4]


Thanks to Kevin Lau for 2 bytes!