How to unit test a Python function that draws PDF graphics?

Question

I\'m writing a CAD application that outputs PDF files using the Cairo graphics library. A lot of the unit testing does not require actually generating the PDF files, such as

Answer 1

You could capture the PDF as a bitmap (or at least a losslessly-compressed) image, and then compare the image generated by each test with a reference image of what it's supposed to look like. Any differences would be flagged as an error for the test.