LSP, formatting and completion

Servers from Mason, formatting from conform, linting from nvim-lint, completion from blink

Language servers

The language packs in nvim/lua/community.lua declare each server; Mason installs it the first time you open a file of that type, and AstroLSP attaches it with the mappings in Keybindings.

Server	Languages	Notes
lua_ls	Lua	lazydev adds the Neovim API
rust_analyzer	Rust	Through rustaceanvim, not lspconfig
ruff	Python	Lint, fix, format, import sorting
ty	Python	Type checking, the Astral checker
vtsls	TypeScript, JavaScript	tsc.nvim for project-wide type errors
html, cssls, emmet_ls	HTML, CSS, SCSS
tailwindcss	Tailwind classes
jsonls	JSON	Schemas from schemastore
yamlls	YAML	Schemas from schemastore
taplo	TOML
marksman	Markdown
bashls	sh, bash, zsh	Runs shellcheck inline
docker_language_server	Dockerfile, compose	hadolint for lint
powershell_es	PowerShell

Space li shows what is attached to the current buffer. :Mason shows what is installed.

Features

• Diagnostics show as virtual text by default; Space ud toggles them, Space uv toggles just the virtual text, gl or Space ld opens the float, Space xx opens Trouble.
• Hover with K, signature help with gK, and blink.cmp pops signature help while you type inside a call.
• Inlay hints start off. Space uh turns them on per buffer.
• CodeLens refreshes on InsertLeave and BufEnter; Space lL runs the lens under the cursor.
• Semantic tokens are on. Space uY switches them off for a buffer if a server paints too much.

Formatting (conform)

Space lf formats the buffer or the visual selection. Formatters resolve per filetype and fall back to the language server when nothing else is registered:

Filetype	Formatter
Lua	stylua
Python	ruff fix, ruff organize imports, ruff format
Rust	rust-analyzer
JS, TS, JSON, CSS, SCSS, HTML, YAML, Markdown	prettierd, then prettier
sh, bash, zsh	shfmt, shellcheck
TOML	taplo

Autoformat on save is off. vim.g.autoformat = false in astrocore.lua sets the default; Space uF flips it for the session and Space uf for one buffer. Space lc opens :ConformInfo when a formatter misbehaves.

Linting (nvim-lint)

Linters run after you save, when you leave insert mode, and a beat after text changes:

Filetype	Linter
Markdown	markdownlint-cli2
YAML	yamllint
sh, zsh	shellcheck
Dockerfile	hadolint

Ruff and ty report through the LSP, so Python needs no separate linter.

Tools

mason-tool-installer owns the ensure_installed list. The packs contribute their servers and tools; mason.lua adds prettierd, markdownlint-cli2 and yamllint. Space pM or :MasonToolsUpdate installs anything missing. mason.nvim itself has no ensure_installed option, so lists placed there are ignored.

Completion (blink.cmp)

Sources: LSP, path, snippets (LuaSnip with friendly-snippets), buffer words. The menu opens as you type, Enter accepts, C-Space shows documentation, and Tab jumps through snippet fields. Space uc turns completion off for a buffer.

Treesitter

Parsers install on demand from the main branch of nvim-treesitter. Highlighting, indentation, folding and text objects are on for every buffer with a parser, and off above 256KB or 10,000 lines. :TSInstall <lang> adds one by hand, :TSUpdate rebuilds them all. :InspectTree shows the syntax tree under the cursor.

Adding a language

1. Check AstroCommunity for a pack and add { import = "astrocommunity.pack.<name>" } to nvim/lua/community.lua.
2. No pack: add the server to mason-lspconfig's ensure_installed through a spec in nvim/lua/plugins/, and set any options under astrolsp.opts.config.<server>.
3. Formatters and linters go in nvim/lua/plugins/format.lua under formatters_by_ft and linters_by_ft, plus the tool name in mason.lua.
4. Restart, then Space pa to install.

Troubleshooting

• Server not attaching: Space li, then :LspLog. Most misses are a tool that Mason has not installed yet; run :MasonToolsUpdate.
• Formatter did nothing: :ConformInfo lists the formatters conform found for the buffer and why it skipped any.
• Treesitter error after an update: :TSUpdate, and if a parser stays broken, delete it from ~/.local/share/nvim/site/parser/ and reopen the file.