• Beware of 'require' at startup in Neovim plugins

    Recently I tagged version 0.9.1 of rainbow-delimiters.nvim. This update got rid of one really nasty mistake I had been dragging along from the very beginning until just recently: every time you started up Neovim a number of require calls would run even if you never called require a single time yourself. In this post I would like to go over how this happened, why it is bad and how I got rid of it. Even though I am using rainbow-delimiters as an example here, everything I am about to say applies to other plugins as well.

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  • Debugging Lua scripts running in Neovim

    In a previous blog post I wrote about testing Lua scripts in Neovim using the busted test framework. Today I want to look at how to debug Lua scripts in Neovim using the Debug Adapter Protocol (DAP). Just as before with busted, our problem is that we need to use Neovim as our Lua interpreter because we want to use Neovim's Lua API. At the same time, the debug adapter expects the Lua interpreter to conform to Lua's command-line interface. That's right: we need another command-line interface adapter.

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  • Testing Neovim plugins with Busted

    The most annoying part about writing plugins for Neovim has been the lack of a good test framework. There are a couple of frameworks, and Vader has been my favourite so far, but they all have their downsides. This made me wonder: why limit myself to Vim/Neovim test frameworks? We have a full Lua runtime, and other people already have solved the testing problem for Lua. Busted does 90% of what we need, so let's fill in the remaining 10%. The following is based on my experience with adding tests to rainbow-delimiters.nvim.

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  • Big change to rainbow-delimiters.nvim

    No, not another rewrite. Much better than that: the long-standing ugliness of highlighting being limited to only one node at a time has been fixed. Previously only one opening node and one closing node could be highlighted. This was perfectly adequate for most languages where you have one opening parenthesis and one closing parenthesis. However, consider HTML: we want to highlight the opening and closing tag, but if we highlight the entire top-level node we also highlight the attributes of the tag, which looks too vibrant. The alternative was highlighting the tag name, but this left the angle brackets without highlighting, which looked jarring as well.

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