vimline-errors

vimline-errors is a plugin for native Vim 9.0 and newer that shows error messages inline, right next to the line of code that has the problem, instead of making you check a separate list or gutter. It is written in Vim script and rebuilt from scratch using Vim 9's own text property virtual text feature, since Vim does not have the extmarks system that similar tools in Neovim rely on.

What makes it different from most diagnostic plugins is that it does not need you to install a linter or language server for each language. Instead, by default it runs the compiler or interpreter you already have for that language in a check only mode, tools like gcc, python3, node, and bash. Out of the box it supports Python, C, C++, JavaScript, shell scripts, Perl, and Lua, and if the matching compiler is not installed on your machine, that filetype just quietly shows nothing. It only catches actual errors, not style or lint warnings, and for that its README points you toward pairing it with the ALE plugin instead.

Setup requires Vim 9.0.0297 or newer built with the plus textprop feature, plus whatever compilers you want checked, and installation works through common plugin managers such as vim-plug or native Vim 9 packages. Once installed, errors appear inline as you type and clear automatically once you fix them, with zero configuration needed, though an options table lets you change things like the icon style, check delay, and which filetypes are ignored.

A standout feature is one keystroke fixes: for C and C++ compiled with gcc or g++, the plugin can apply the compiler's own suggested fix directly to your code, such as inserting a missing semicolon or renaming a misspelled identifier. Other languages fall back to a comment out action. Fixes only apply if the file has not changed since the last check, so a stale suggestion can never corrupt your buffer. The project is released under the MIT license and welcomes contributions.