A hard fork of Ionide-vim, now providing an initial Clef client for Neovim 0.11 or newer. It connects Neovim's built-in LSP client to an explicitly configured server. The .NET-hosted Lattice service under Composer now supplies a local CCS-backed VSCode demo; its Neovim semantic gate remains work. The Lattice integration plan coordinates the compiler and editor gates.
Add this repository to Neovim's runtime path through your plugin manager, then supply the actual command for a compatible stdio LSP server:
require('lattice').setup({
cmd = { 'dotnet', '/absolute/path/to/Composer/src/Lattice.Server/bin/Debug/net10.0/Lattice.Server.dll' },
})Build that DLL from Composer with dotnet build src/Lattice.Server/Lattice.Server.fsproj. Replace the absolute prefix with your checkout location. The server selects the one .fidproj in the workspace root; add --project and its path when several are present. The executable and arguments are passed directly; this plugin does not download a server, add FSAC flags, or select a default command. A missing or invalid command produces a configuration error.
File detection registers .clef as clef. The client attaches named Clef buffers beneath the nearest directory containing a .fidproj. This is a registration hint: CCS still owns project interpretation, membership, source order and dependencies. Several manifests in one directory do not make the client choose a project. There is no .git or working-directory fallback; untitled files and .clefx support remain pending.
Standard Neovim LSP handling supplies the capabilities the server advertises, including hover and diagnostics. The client adds no private fsharp/* requests or automatic code-lens polling. It does not infer dimensions, assign proof verdicts or reconstruct compiler facts.
Calling setup again with the same command is safe. A changed command replaces this plugin's clients. To control their lifetime explicitly:
require('lattice').restart()
require('lattice').stop() -- disables automatic attachment until setup is called againRestart and reconfiguration request graceful shutdown and wait for client cleanup before replacement; an unresponsive process is stopped after the grace period. Clients for nested project roots remain separate. Renaming a buffer outside its former root detaches it from that client.
The inherited automatic FSAC activation and F# filetype callbacks are disconnected. Opening .fs or .fsproj does not start an F# server or install FSI commands through this plugin. The retained F# implementation is reference material, not a second backend for the Clef client. Plain Vim integration remains pending; it is not covered by the Neovim implementation or tests. Clef lexical highlighting and semantic-token coverage also need their own validation; the companion clef-grammar repository supplies a TextMate baseline for consumers that support it.
With Neovim 0.11+ and Node.js available, run:
bash tests/run.shThe gate runs in real headless Neovim against a small stdio fixture server. It checks explicit command arguments, file registration, nearest project roots, initialization, document open/change/close, Unicode full-text updates, hover, diagnostic clearing, capability handling, mixed-file isolation and setup/restart/shutdown. It also checks that no FSAC-private or unadvertised code-lens request is sent. The current run was validated with Neovim 0.12.5.
The fixture's FIXTURE001 diagnostic and hover text test transport only. They are not CCS type checking or proof results. The compiler integration gate remains the shared measured-type fixture: hover preserves dimensional identity, an incompatible-dimension edit produces the compiler's diagnostic, and a correction clears it without stale results replacing current ones. Proof evidence and its invalidation must follow compiler-owned query contracts as they land. Plain Vim needs a separate client gate before claiming support.
Composer M-01 §5 adds target-specific numeric and concurrency evidence to the CCS/Lattice plan. The client displays compiler-owned profile, capability and obligation results; it does not infer representation choices or wait relationships. The pending Neovim semantic gate should include exact diagnostics and unsaved repair after a target capability change, preserving graph/source version and rejecting stale responses. Protocol-fixture success remains distinct from compiler acceptance. No richer query support or Plain Vim implementation is claimed by this planning update. Coordinated revisions belong to the coverage waypoints.
The long-form upstream README and Vim help describe the inherited Ionide-vim behavior. Preserve them as heritage rather than using their FSAC commands as Lattice setup instructions. See IONIDE_HERITAGE.md and LICENSE.md for attribution. Ionide-vim is the work of the Ionide community.