100% unit test coverage

I write a lot of stupid and useless unit tests. I confess that I'm aiming towards the elusive 100% test coverage. Sure, I'll never get there, and I realize it is not even a desirable goal. After an assessed threshold, we start to get diminishing returns. Why do I keep writing wrong tests then? Which unit tests should I leave out?

My case is that it is tricky to write a large codebase with only valuable tests. I dare say that some (minority) of the essential tests might have outright bad practices where they end up testing how well I can mock stuff. The value of the test is not predetermined; hence I keep writing a lot of seemingly poor ones.

There is an argument that high test coverage does not strongly reduce bugs and increase maintainability. That is likely true. Nonetheless, it is not so apparent which tests will avoid the most bugs or are the most useful in refactoring in the long term. The cliché is that requirements change, sometimes towards unknown directions.

It is more time-consuming but ultimately more robust to test everything, and trust that some semi-unknown set is the proper safeguard against bugs and most valuable while refactoring. Is this approach practical? In some cases, yes. Take SQLite, famous for its superb reliability, achieved partially by 100% machine code level test coverage.

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I'm not a passionate developer

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Extracting object properties from an IFC file with IfcOpenShell

Besides the object geometry information, IFC files may contain properties for the IFC objects. The properties can be, for example, some predefined dimension information such as an object volume or a choice of material. Some of the properties are predefined in the IFC standards, but custom ones can be added. IFC files can be massive and resource-intensive to process, so in some cases, it helps to separate the object properties from the geometry data. IfcOpenShell is a toolset for processing IFC files. It is written mostly in C++ but also provides a Python interface. To read an IFC file >>> ifc_file = ifcopenshell.open("model.ifc") Fetch all objects of type IfcSlab >>> slab = ifc_file.by_type("IfcSlab")[1] Get the list of properties >>> slab.IsDefinedBy (#145075=IfcRelDefinesByType('2_fok0__fAcBZmMlQcYwie',#1,$,$,(#27,#59),#145074), #145140=IfcRelDefinesByProperties('3U2LyORgXC2f_hWf6I16C1',#1,$,$,(#27,#59),#145141), #145142

Hubristic developer

Almost half of any Finnish generation goes through a shared experience: the conscript army. An integral part of that experience is learning military slang, a set way people in the army talk. The stories told with said jargon often spread outside of the barracks. It is not uncommon to hear strangers bonding together over beers reminiscing and feeling nostalgic about freezing cold nights spent in tents. There is a similar phenomenon detectable among us coders. To be part of the coder tribe, there is at least one type of story that one must master. That is - of course - ranting about legacy codebases. "Can you believe how much of a mess the previous coders left? Hear, hear!" There is no better way to onboard a new team member than to blame some previous B-team for all the murky parts of the system at hand. This can be seen as harmless, a subject for a good meme . Rarely do we hold real grudges against "the legacy folk" and can be the best of friends in a social gather

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