umple.nvim

Neovim plugin for the Umple modeling language. Provides diagnostics, code completion, go-to-definition, and syntax highlighting for .ump files.

Requirements

• Neovim 0.9+ (0.10+ recommended)
• Node.js 18+ (for running the LSP server)
• A C compiler (cc or gcc) for compiling the tree-sitter parser
• Java 11+ (optional — only needed for diagnostics)
• A plugin manager — this guide uses lazy.nvim

Installing prerequisites

macOS (via Homebrew):

brew install neovim node
brew install openjdk  # optional, for diagnostics

Ubuntu/Debian:

sudo apt install neovim nodejs npm build-essential
sudo apt install default-jdk  # optional, for diagnostics

Setting up lazy.nvim

If you don't have a plugin manager yet, follow the lazy.nvim installation guide.

Installation

Add this to your lazy.nvim plugin list:

{
  'umple/umple.nvim',
  build = './scripts/build.sh',
  dependencies = {
    'neovim/nvim-lspconfig',
    'nvim-treesitter/nvim-treesitter',
  },
  config = function()
    require("umple-lsp").setup()
  end,
}

The build script downloads the LSP server from npm and fetches the tree-sitter grammar. The tree-sitter parser is compiled automatically on first load — no manual steps needed.

Auto-completion (recommended)

For auto-popup completion, install a completion plugin such as nvim-cmp with cmp-nvim-lsp. Without one, the LSP server still provides completions but you won't see them automatically.

Configuration

require("umple-lsp").setup({
  port = 5556,  -- UmpleSync port (default: 5556)
  on_attach = function(client, bufnr)
    -- your custom keybindings
  end,
})

Default keybindings

Key	Action
gd	Go to definition
<leader>e	Show diagnostics float
[d	Previous diagnostic
]d	Next diagnostic

Features

• Diagnostics: Real-time error and warning detection (requires Java)
• Go-to-definition: Jump to classes, interfaces, traits, enums, attributes, methods, state machines, states, associations, mixsets, requirements, and use statements
• Code completion: Context-aware keyword and symbol completion
• Syntax highlighting: Via tree-sitter grammar (compiled automatically)

Updating

:Lazy update umple.nvim

This pulls the latest plugin code and re-runs the build script (which updates the LSP server and tree-sitter grammar).

Troubleshooting

No syntax highlighting

The plugin compiles the tree-sitter parser on first load. If it fails:

1. Make sure you have a C compiler: cc --version or gcc --version
2. Delete the cached parser and restart Neovim to recompile:

   rm -f ~/.local/share/nvim/site/parser/umple.so
   rm -rf ~/.local/share/nvim/site/queries/umple

No diagnostics

Diagnostics require Java 11+. Verify: java -version

LSP not starting

1. Check that Node.js is installed: node --version
2. Run :LspLog in Neovim to see server errors
3. Rebuild the plugin: :Lazy build umple.nvim

Development

To test local changes to the LSP server:

1. Clone both repos side by side:

workspace/
├── umple-lsp/       # LSP server monorepo
└── umple.nvim/      # This plugin

2. Build the server locally:

cd umple-lsp
npm install
npm run compile
npm run download-jar

3. Override the plugin's paths to use your local build:

{
  dir = '/path/to/umple.nvim',
  dependencies = {
    'neovim/nvim-lspconfig',
    'nvim-treesitter/nvim-treesitter',
  },
  config = function()
    require("umple-lsp").setup({
      plugin_dir = '/path/to/umple.nvim',
    })
  end,
}

Then symlink the local server into the plugin's expected locations:

cd umple.nvim
# Symlink tree-sitter grammar
ln -sf ../umple-lsp/packages/tree-sitter-umple tree-sitter-umple
# Symlink local server into node_modules (jar is already inside packages/server/)
mkdir -p node_modules
ln -sf ../../umple-lsp/packages/server node_modules/umple-lsp-server

After making changes to the server, recompile and restart:

cd umple-lsp
npm run compile       # Server-only changes
npm run build-grammar # After grammar.js changes (regenerates parser + WASM + compiles)

Then in Neovim: :LspRestart

After grammar changes, also delete the cached native parser so Neovim recompiles it:

rm -f ~/.local/share/nvim/site/parser/umple.so
rm -rf ~/.local/share/nvim/site/queries/umple

How it works

The build script installs the pre-compiled umple-lsp-server from npm, downloads umplesync.jar for diagnostics, and extracts the tree-sitter grammar (src/parser.c + queries/) from the umple-lsp repo. The plugin compiles the tree-sitter parser automatically on first load (into ~/.local/share/nvim/site/parser/umple.so) and points Neovim's LSP client at the npm-installed server.