Here are some examples for some unit tests to handle some of the common and edge cases; more should be added!

• parsing of various matrices (tab delineated, multiple space delineated, spaces before first number, wrong number of elements, not-actually-a-valid-rotation, etc)
• parsing of various vectors (see matrix formatting cases)
• check default values for com, output, etc. on rigid bodies
• check that mass/com "offsets" work properly: they offset by the correct amount, but don't affect other properties.
• check that mass/com "overrides" work properly: they offset by the correct amount, but don't affect other properties.
• create example library -- one for each kit -- and assert that the computed output positions and center of mass positions match for a vector of zero positions, as well as assorted random joint angles. Only test non-tree kits.

Allowed cases:

• parsing of empty <output> elements should not fail
• Mixed index/non-index usage of <output> element children for different parents, as long as there is consistency in each single parent
• <output> contains a chain of model elements.
• <output> contains a child element with multiple <output> elements (allowed)
• Check parts of the "example library" above that contain trees.

Error cases:

• The number of <output> elements exceeds the allowed number for a built in type