| Element | Missed Instructions | Cov. | Missed Branches | Cov. | Missed | Cxty | Missed | Lines | Missed | Methods |
| Total | 75 of 200 | 62% | 14 of 22 | 36% | 11 | 20 | 14 | 36 | 2 | 9 |
| IOOutputStream(IRubyObject, Encoding, boolean, boolean) | | 55% | | 43% | 5 | 8 | 5 | 13 | 0 | 1 |
| close() | | 0% | | 0% | 3 | 3 | 5 | 5 | 1 | 1 |
| write(byte[], int, int) | | 81% | | 50% | 1 | 2 | 1 | 4 | 0 | 1 |
| IOOutputStream(IRubyObject, Encoding) | | 0% | n/a | 1 | 1 | 2 | 2 | 1 | 1 | |
| write(int) | | 87% | | 50% | 1 | 2 | 1 | 5 | 0 | 1 |
| IOOutputStream(IRubyObject, boolean, boolean) | | 100% | n/a | 0 | 1 | 0 | 2 | 0 | 1 | |
| write(byte[]) | | 100% | n/a | 0 | 1 | 0 | 2 | 0 | 1 | |
| IOOutputStream(IRubyObject) | | 100% | n/a | 0 | 1 | 0 | 2 | 0 | 1 | |
| static {...} | | 100% | n/a | 0 | 1 | 0 | 1 | 0 | 1 |