recent bug fix discussion for
bar saw a small error almost slip through due to lack of BISTs for most plotting functions (most only have demo blocks requiring human visual error checking). While coding the patch I was wondering whether such functions could have useful tests derived from the handles that most of these functions return. In the case of
bar, would the properties be present to probe for correct rectangular patch positions/coordinates, etc.
How messy/fragile would that be? Would a innocuous change to an underlying draw function break all of the tests by, say, a vertex ordering change, even when figure is actually still correct. Etc. we wouldn’t want something like that to require manually rewriting all such BISTs. Would there be a way to make it less problematic? are the right useful property hooks even there to probe in the first place?
second, if this approach works, how big a task would it be to start going through “all” of the functions in core octave that it would apply to? is there a way to screen functions needing these kind of tests? (e.g., bar now has tests, but just for input error handling. so it wouldn’t show up in a set of functions without any tests)