| Element | Missed Instructions | Cov. | Missed Branches | Cov. | Missed | Cxty | Missed | Lines | Missed | Methods |
| Total | 92 of 160 | 42% | 18 of 30 | 40% | 16 | 19 | 1 | 7 | 3 | 4 |
| unionOperationToCeylon(Tree.UnionOp, Callable) | | 50% | | 40% | 13 | 16 | 0 | 6 | 0 | 1 |
| unionOperationToCeylon$update(Tree.UnionOp) | | 0% | n/a | 1 | 1 | 1 | 1 | 1 | 1 | |
| unionOperationToCeylon(Tree.UnionOp) | | 0% | n/a | 1 | 1 | 1 | 1 | 1 | 1 | |
| unionOperationToCeylon_() | | 0% | n/a | 1 | 1 | 0 | 0 | 1 | 1 |