To prepare for a live demo of agentic coding, I created two branches based off a historic commit and checked each one out in a separate worktree. The idea was to recreate commit b using two LLM agents, one in each branch, to compare their a…
A Bash script I was working on had a while read loop that processed Git commit SHAs: but it did nothing when the git log command only piped one SHA in. Why? Because read is designed to work with sequences of lines and lines need to end with…
git range-diff lets you compare two ranges of commits. One way of invoking it is: I’ve used it recently to compare two versions of the same pull request branch, before and after a force-push. In a GitHub action, this can be implemented as:
To run a shell command on each commit in an interactive rebase, use: after each commit in the rebase todo list. You can edit or remove the commands if you like. You can even add exec lines manually even if you didn’t start the rebase with t…
I recently gained a deeper understanding of when to use stdout and stderr in shell scripts. The definitions in Wikipedia are: Standard output is a stream to which a program writes its output data. Standard error is another output stream typ…
It’s sometimes useful to see the sizes of each Git commit — “size” as in the number of line additions and deletions. I needed this recently when looking to break up a Github pull request into smaller, easier-to-review pull requests. I wante…
There’s several gotchas to be aware of when using time_machine with Pytest fixtures. For one, time_machine’s control of the system clock does not apply to fixture functions included in a test’s signature. Further, you can’t fix this test by…
After a recent brew upgrade I discovered that exa, the modern replacement for ls, had stopped being maintained and had been replaced by eza. Hence, after installing eza, I updated my shell aliases: where ll is a long listing which removes p…
You can use Simon Willison’s excellent llm tool to query or edit Vim buffers by piping the contents of a visual selection to the llm. Select some text in visual mode then hit : to enter command mode with range selected (:'). Then you can do…
In a large monorepo, it’s helpful to have a .github/CODEOWNERS file that maps filepaths to owning teams, covering as much of the codebase as possible. But how do you measure how much of the codebase is covered by the codeowners file? There’…
I was surprised to learn today that this test passes: This is because time_machine.travel starts ticking after the first call to the system clock, not from when the context manager is entered. This is documented but is quite counter intuiti…
Python’s unittest.mock package lets you create wrapper mocks that forward on calls to the original object. This is done using the wraps parameter - e.g. Such test doubles are commonly known as spies. It’s possible to intercept wrapped calls…