cmp-go-deep

A Go deep-completion source for nvim-cmp / blink.cmp, that works alongside cmp-nvim-lsp / blink.cmp's LSP source and provides completion suggestions for "UNIMPORTED LOCAL, INTERNAL, AND VENDORED PACKAGES ONLY".

Why?

At the time of writing, the Go Language Server ([email protected]) doesn't seem to support deep completions for unimported packages. For example, with deep completion enabled, typing 'cha' could suggest 'rand.NewChaCha8()' as a possible completion option - but that is not the case no matter how high the completion budget is set for gopls.

How?

Query gopls's workspace/symbol endpoint, cache the results using sqlite, convert the resulting SymbolInformation into completionItemKinds, filter the results to only include the ones that are unimported, then finally feed them back into nvim-cmp / blink.cmp

---

⚠️ it might take a while for the packages to be indexed by gopls in huge codebases

Demo

• Note: Due to how gopls indexes packages, completions for standard library packages are not available until at least one of them is manually imported.

---

Requirements

• nvim-cmp OR blink.cmp
• sqlite.lua

Setup

Lazy.nvim

- nvim-cmp

{
	"hrsh7th/nvim-cmp",
	dependencies = {
		{ "samiulsami/cmp-go-deep", dependencies = { "kkharji/sqlite.lua" } },
	},
	...
	require("cmp").setup({
		sources = {{
			name = "go_deep",
			keyword_length = 3,
			max_item_count = 5,
			---@module "cmp_go_deep"
			---@type cmp_go_deep.Options
			option = {
				-- See below for configuration options
			},
		}},
	})
}

- blink.cmp (requires saghen/blink.compat)

{
	"saghen/blink.cmp",
	dependencies = {
		{ "samiulsami/cmp-go-deep", dependencies = { "kkharji/sqlite.lua" } },
		{ "saghen/blink.compat" },
	},
	opts = {
		sources = {
			default = {
				"go_deep",
			},
			providers = {
				go_deep = {
					name = "go_deep",
					module = "blink.compat.source",
					min_keyword_length = 3,
					max_items = 5,
					---@module "cmp_go_deep"
					---@type cmp_go_deep.Options
					opts = {
						-- See below for configuration options
					},
				},
			},
		},
	},
}

Default options

{
	-- Enable/disable notifications.
	notifications = true,

	-- Filetypes to enable the source for.
	filetypes = { "go" },

	-- How to get documentation for Go symbols.
	-- options:
	-- "hover" - LSP 'textDocument/hover'. Prettier.
	-- "regex" - faster and simpler.
	get_documentation_implementation = "regex",

	-- How to get the package names.
	-- options:
	-- "treesitter" - accurate but slower.
	-- "regex" - faster but can fail in edge cases.
	get_package_name_implementation = "regex",

	-- Whether to exclude vendored packages from completions.
	exclude_vendored_packages = false,

	-- Timeout in milliseconds for fetching documentation.
	-- Controls how long to wait for documentation to load.
	documentation_wait_timeout_ms = 100,

	-- Maximum time (in milliseconds) to wait before "locking-in" the current request and sending it to gopls.
	debounce_gopls_requests_ms = 0

	-- Path to store the SQLite database
	-- Default: "~/.local/share/nvim/cmp_go_deep.sqlite3"
	db_path = vim.fn.stdpath("data") .. "/cmp_go_deep.sqlite3",
}

---

TODO

• Cache results for faster completions.
• Cross-project cache sharing for internal packages.
• Better memory usage.
• Don't ignore package names while matching symbols.
• Archive after this issue is properly addressed.