I do sometimes. It depends. I want to do more of it. Here are cases where I've genuinely found it valuable and enjoyable to write tests ahead of time: Some th

I do sometimes. It depends. I want to do more of it. Here are cases where I've genuinely found it valuable and enjoyable to write tests ahead of time: Some things are difficult to test. I've had things that involve a ton of setup, or a configuration with an external system. With tests you can automate that setup and run through a scenario. You can mock external systems. This gives you a way of setting up a scaffold into which your implementation will fall. Things that involve time are also great for setting up test cases. Imagine some functionality where you do something, and need 3 weeks to pass before something else happens. Testing that by hand is effectively impossible. With test tools, you can fake the passing of time and have confirmation that your code is working well. Think about when you are writing some functionality that requires some involved logic, and UIs. It makes sense to implement the logic first. But how do you even invoke it without a UI? Write a test case! You can debug it through test runs without needing to invest time in writing a UI. Bugs! Something esoteric breaks. I often write a test case named test_this_and_that__jira2987 where 2987 is the ticket number where the issue came up. I write up a test case replicating the bug in with only essential conditions. Fixing it is a lot more enjoyable than trying to walk through the replication script by hand. Additionally, it results in a good regression test that makes sure my team does not reintroduce the bug again.