neovim/runtime/lua/vim/lsp/semantic_tokens.lua
jdrouhard 5e6a288ce7
fix(lsp): followup fixes for semantic tokens support (#21357)
1. The algorithm for applying edits was slightly incorrect. It needs to
   preserve the original token list as the edits are applied instead of
   mutating it as it iterates. From the spec:

   Semantic token edits behave conceptually like text edits on
   documents: if an edit description consists of n edits all n edits are
   based on the same state Sm of the number array. They will move the
   number array from state Sm to Sm+1.

2. Schedule the semantic token engine start() call in the
   client._on_attach() function so that users who schedule_wrap() their
   config.on_attach() functions (like nvim-lspconfig does) can still
   disable semantic tokens by deleting the semanticTokensProvider from
   their server capabilities.
2022-12-09 11:54:09 +01:00

642 lines
20 KiB
Lua

local api = vim.api
local handlers = require('vim.lsp.handlers')
local util = require('vim.lsp.util')
--- @class STTokenRange
--- @field line number line number 0-based
--- @field start_col number start column 0-based
--- @field end_col number end column 0-based
--- @field type string token type as string
--- @field modifiers string[] token modifiers as strings
--- @field extmark_added boolean whether this extmark has been added to the buffer yet
---
--- @class STCurrentResult
--- @field version number document version associated with this result
--- @field result_id string resultId from the server; used with delta requests
--- @field highlights STTokenRange[] cache of highlight ranges for this document version
--- @field tokens number[] raw token array as received by the server. used for calculating delta responses
--- @field namespace_cleared boolean whether the namespace was cleared for this result yet
---
--- @class STActiveRequest
--- @field request_id number the LSP request ID of the most recent request sent to the server
--- @field version number the document version associated with the most recent request
---
--- @class STClientState
--- @field namespace number
--- @field active_request STActiveRequest
--- @field current_result STCurrentResult
---@class STHighlighter
---@field active table<number, STHighlighter>
---@field bufnr number
---@field augroup number augroup for buffer events
---@field debounce number milliseconds to debounce requests for new tokens
---@field timer table uv_timer for debouncing requests for new tokens
---@field client_state table<number, STClientState>
local STHighlighter = { active = {} }
---@private
local function binary_search(tokens, line)
local lo = 1
local hi = #tokens
while lo < hi do
local mid = math.floor((lo + hi) / 2)
if tokens[mid].line < line then
lo = mid + 1
else
hi = mid
end
end
return lo
end
--- Extracts modifier strings from the encoded number in the token array
---
---@private
---@return string[]
local function modifiers_from_number(x, modifiers_table)
---@private
local function _get_bit(n, k)
--TODO(jdrouhard): remove once `bit` module is available for non-LuaJIT
if _G.bit then
return _G.bit.band(_G.bit.rshift(n, k), 1)
else
return math.floor((n / math.pow(2, k)) % 2)
end
end
local modifiers = {}
for i = 0, #modifiers_table - 1 do
local b = _get_bit(x, i)
if b == 1 then
modifiers[#modifiers + 1] = modifiers_table[i + 1]
end
end
return modifiers
end
--- Converts a raw token list to a list of highlight ranges used by the on_win callback
---
---@private
---@return STTokenRange[]
local function tokens_to_ranges(data, bufnr, client)
local legend = client.server_capabilities.semanticTokensProvider.legend
local token_types = legend.tokenTypes
local token_modifiers = legend.tokenModifiers
local ranges = {}
local line
local start_char = 0
for i = 1, #data, 5 do
local delta_line = data[i]
line = line and line + delta_line or delta_line
local delta_start = data[i + 1]
start_char = delta_line == 0 and start_char + delta_start or delta_start
-- data[i+3] +1 because Lua tables are 1-indexed
local token_type = token_types[data[i + 3] + 1]
local modifiers = modifiers_from_number(data[i + 4], token_modifiers)
---@private
local function _get_byte_pos(char_pos)
return util._get_line_byte_from_position(bufnr, {
line = line,
character = char_pos,
}, client.offset_encoding)
end
local start_col = _get_byte_pos(start_char)
local end_col = _get_byte_pos(start_char + data[i + 2])
if token_type then
ranges[#ranges + 1] = {
line = line,
start_col = start_col,
end_col = end_col,
type = token_type,
modifiers = modifiers,
extmark_added = false,
}
end
end
return ranges
end
--- Construct a new STHighlighter for the buffer
---
---@private
---@param bufnr number
function STHighlighter.new(bufnr)
local self = setmetatable({}, { __index = STHighlighter })
self.bufnr = bufnr
self.augroup = api.nvim_create_augroup('vim_lsp_semantic_tokens:' .. bufnr, { clear = true })
self.client_state = {}
STHighlighter.active[bufnr] = self
api.nvim_buf_attach(bufnr, false, {
on_lines = function(_, buf)
local highlighter = STHighlighter.active[buf]
if not highlighter then
return true
end
highlighter:on_change()
end,
on_reload = function(_, buf)
local highlighter = STHighlighter.active[buf]
if highlighter then
highlighter:reset()
highlighter:send_request()
end
end,
on_detach = function(_, buf)
local highlighter = STHighlighter.active[buf]
if highlighter then
highlighter:destroy()
end
end,
})
api.nvim_create_autocmd({ 'BufWinEnter', 'InsertLeave' }, {
buffer = self.bufnr,
group = self.augroup,
callback = function()
self:send_request()
end,
})
api.nvim_create_autocmd('LspDetach', {
buffer = self.bufnr,
group = self.augroup,
callback = function(args)
self:detach(args.data.client_id)
if vim.tbl_isempty(self.client_state) then
self:destroy()
end
end,
})
return self
end
---@private
function STHighlighter:destroy()
for client_id, _ in pairs(self.client_state) do
self:detach(client_id)
end
api.nvim_del_augroup_by_id(self.augroup)
STHighlighter.active[self.bufnr] = nil
end
---@private
function STHighlighter:attach(client_id)
local state = self.client_state[client_id]
if not state then
state = {
namespace = api.nvim_create_namespace('vim_lsp_semantic_tokens:' .. client_id),
active_request = {},
current_result = {},
}
self.client_state[client_id] = state
end
end
---@private
function STHighlighter:detach(client_id)
local state = self.client_state[client_id]
if state then
--TODO: delete namespace if/when that becomes possible
api.nvim_buf_clear_namespace(self.bufnr, state.namespace, 0, -1)
self.client_state[client_id] = nil
end
end
--- This is the entry point for getting all the tokens in a buffer.
---
--- For the given clients (or all attached, if not provided), this sends a request
--- to ask for semantic tokens. If the server supports delta requests, that will
--- be prioritized if we have a previous requestId and token array.
---
--- This function will skip servers where there is an already an active request in
--- flight for the same version. If there is a stale request in flight, that is
--- cancelled prior to sending a new one.
---
--- Finally, if the request was successful, the requestId and document version
--- are saved to facilitate document synchronization in the response.
---
---@private
function STHighlighter:send_request()
local version = util.buf_versions[self.bufnr]
self:reset_timer()
for client_id, state in pairs(self.client_state) do
local client = vim.lsp.get_client_by_id(client_id)
local current_result = state.current_result
local active_request = state.active_request
-- Only send a request for this client if the current result is out of date and
-- there isn't a current a request in flight for this version
if client and current_result.version ~= version and active_request.version ~= version then
-- cancel stale in-flight request
if active_request.request_id then
client.cancel_request(active_request.request_id)
active_request = {}
state.active_request = active_request
end
local spec = client.server_capabilities.semanticTokensProvider.full
local hasEditProvider = type(spec) == 'table' and spec.delta
local params = { textDocument = util.make_text_document_params(self.bufnr) }
local method = 'textDocument/semanticTokens/full'
if hasEditProvider and current_result.result_id then
method = method .. '/delta'
params.previousResultId = current_result.result_id
end
local success, request_id = client.request(method, params, function(err, response, ctx)
-- look client up again using ctx.client_id instead of using a captured
-- client object
local c = vim.lsp.get_client_by_id(ctx.client_id)
local highlighter = STHighlighter.active[ctx.bufnr]
if not err and c and highlighter then
highlighter:process_response(response, c, version)
end
end, self.bufnr)
if success then
active_request.request_id = request_id
active_request.version = version
end
end
end
end
--- This function will parse the semantic token responses and set up the cache
--- (current_result). It also performs document synchronization by checking the
--- version of the document associated with the resulting request_id and only
--- performing work if the response is not out-of-date.
---
--- Delta edits are applied if necessary, and new highlight ranges are calculated
--- and stored in the buffer state.
---
--- Finally, a redraw command is issued to force nvim to redraw the screen to
--- pick up changed highlight tokens.
---
---@private
function STHighlighter:process_response(response, client, version)
local state = self.client_state[client.id]
if not state then
return
end
-- ignore stale responses
if state.active_request.version and version ~= state.active_request.version then
return
end
-- reset active request
state.active_request = {}
-- if we have a response to a delta request, update the state of our tokens
-- appropriately. if it's a full response, just use that
local tokens
local token_edits = response.edits
if token_edits then
table.sort(token_edits, function(a, b)
return a.start < b.start
end)
tokens = {}
local old_tokens = state.current_result.tokens
local idx = 1
for _, token_edit in ipairs(token_edits) do
vim.list_extend(tokens, old_tokens, idx, token_edit.start)
vim.list_extend(tokens, token_edit.data)
idx = token_edit.start + token_edit.deleteCount + 1
end
vim.list_extend(tokens, old_tokens, idx)
else
tokens = response.data
end
-- Update the state with the new results
local current_result = state.current_result
current_result.version = version
current_result.result_id = response.resultId
current_result.tokens = tokens
current_result.highlights = tokens_to_ranges(tokens, self.bufnr, client)
current_result.namespace_cleared = false
api.nvim_command('redraw!')
end
--- on_win handler for the decoration provider (see |nvim_set_decoration_provider|)
---
--- If there is a current result for the buffer and the version matches the
--- current document version, then the tokens are valid and can be applied. As
--- the buffer is drawn, this function will add extmark highlights for every
--- token in the range of visible lines. Once a highlight has been added, it
--- sticks around until the document changes and there's a new set of matching
--- highlight tokens available.
---
--- If this is the first time a buffer is being drawn with a new set of
--- highlights for the current document version, the namespace is cleared to
--- remove extmarks from the last version. It's done here instead of the response
--- handler to avoid the "blink" that occurs due to the timing between the
--- response handler and the actual redraw.
---
---@private
function STHighlighter:on_win(topline, botline)
for _, state in pairs(self.client_state) do
local current_result = state.current_result
if current_result.version and current_result.version == util.buf_versions[self.bufnr] then
if not current_result.namespace_cleared then
api.nvim_buf_clear_namespace(self.bufnr, state.namespace, 0, -1)
current_result.namespace_cleared = true
end
-- We can't use ephemeral extmarks because the buffer updates are not in
-- sync with the list of semantic tokens. There's a delay between the
-- buffer changing and when the LSP server can respond with updated
-- tokens, and we don't want to "blink" the token highlights while
-- updates are in flight, and we don't want to use stale tokens because
-- they likely won't line up right with the actual buffer.
--
-- Instead, we have to use normal extmarks that can attach to locations
-- in the buffer and are persisted between redraws.
local highlights = current_result.highlights
local idx = binary_search(highlights, topline)
for i = idx, #highlights do
local token = highlights[i]
if token.line > botline then
break
end
if not token.extmark_added then
-- `strict = false` is necessary here for the 1% of cases where the
-- current result doesn't actually match the buffer contents. Some
-- LSP servers can respond with stale tokens on requests if they are
-- still processing changes from a didChange notification.
--
-- LSP servers that do this _should_ follow up known stale responses
-- with a refresh notification once they've finished processing the
-- didChange notification, which would re-synchronize the tokens from
-- our end.
--
-- The server I know of that does this is clangd when the preamble of
-- a file changes and the token request is processed with a stale
-- preamble while the new one is still being built. Once the preamble
-- finishes, clangd sends a refresh request which lets the client
-- re-synchronize the tokens.
api.nvim_buf_set_extmark(self.bufnr, state.namespace, token.line, token.start_col, {
hl_group = '@' .. token.type,
end_col = token.end_col,
priority = vim.highlight.priorities.semantic_tokens,
strict = false,
})
--TODO(jdrouhard): do something with the modifiers
token.extmark_added = true
end
end
end
end
end
--- Reset the buffer's highlighting state and clears the extmark highlights.
---
---@private
function STHighlighter:reset()
for client_id, state in pairs(self.client_state) do
api.nvim_buf_clear_namespace(self.bufnr, state.namespace, 0, -1)
state.current_result = {}
if state.active_request.request_id then
local client = vim.lsp.get_client_by_id(client_id)
assert(client)
client.cancel_request(state.active_request.request_id)
state.active_request = {}
end
end
end
--- Mark a client's results as dirty. This method will cancel any active
--- requests to the server and pause new highlights from being added
--- in the on_win callback. The rest of the current results are saved
--- in case the server supports delta requests.
---
---@private
---@param client_id number
function STHighlighter:mark_dirty(client_id)
local state = self.client_state[client_id]
assert(state)
-- if we clear the version from current_result, it'll cause the
-- next request to be sent and will also pause new highlights
-- from being added in on_win until a new result comes from
-- the server
if state.current_result then
state.current_result.version = nil
end
if state.active_request.request_id then
local client = vim.lsp.get_client_by_id(client_id)
assert(client)
client.cancel_request(state.active_request.request_id)
state.active_request = {}
end
end
---@private
function STHighlighter:on_change()
self:reset_timer()
if self.debounce > 0 then
self.timer = vim.defer_fn(function()
self:send_request()
end, self.debounce)
else
self:send_request()
end
end
---@private
function STHighlighter:reset_timer()
local timer = self.timer
if timer then
self.timer = nil
if not timer:is_closing() then
timer:stop()
timer:close()
end
end
end
local M = {}
--- Start the semantic token highlighting engine for the given buffer with the
--- given client. The client must already be attached to the buffer.
---
--- NOTE: This is currently called automatically by |vim.lsp.buf_attach_client()|. To
--- opt-out of semantic highlighting with a server that supports it, you can
--- delete the semanticTokensProvider table from the {server_capabilities} of
--- your client in your |LspAttach| callback or your configuration's
--- `on_attach` callback.
---
--- <pre>lua
--- client.server_capabilities.semanticTokensProvider = nil
--- </pre>
---
---@param bufnr number
---@param client_id number
---@param opts (nil|table) Optional keyword arguments
--- - debounce (number, default: 200): Debounce token requests
--- to the server by the given number in milliseconds
function M.start(bufnr, client_id, opts)
vim.validate({
bufnr = { bufnr, 'n', false },
client_id = { client_id, 'n', false },
})
opts = opts or {}
assert(
(not opts.debounce or type(opts.debounce) == 'number'),
'opts.debounce must be a number with the debounce time in milliseconds'
)
local client = vim.lsp.get_client_by_id(client_id)
if not client then
vim.notify('[LSP] No client with id ' .. client_id, vim.log.levels.ERROR)
return
end
if not vim.lsp.buf_is_attached(bufnr, client_id) then
vim.notify(
'[LSP] Client with id ' .. client_id .. ' not attached to buffer ' .. bufnr,
vim.log.levels.WARN
)
return
end
if not vim.tbl_get(client.server_capabilities, 'semanticTokensProvider', 'full') then
vim.notify('[LSP] Server does not support semantic tokens', vim.log.levels.WARN)
return
end
local highlighter = STHighlighter.active[bufnr]
if not highlighter then
highlighter = STHighlighter.new(bufnr)
highlighter.debounce = opts.debounce or 200
else
highlighter.debounce = math.max(highlighter.debounce, opts.debounce or 200)
end
highlighter:attach(client_id)
highlighter:send_request()
end
--- Stop the semantic token highlighting engine for the given buffer with the
--- given client.
---
--- NOTE: This is automatically called by a |LspDetach| autocmd that is set up as part
--- of `start()`, so you should only need this function to manually disengage the semantic
--- token engine without fully detaching the LSP client from the buffer.
---
---@param bufnr number
---@param client_id number
function M.stop(bufnr, client_id)
vim.validate({
bufnr = { bufnr, 'n', false },
client_id = { client_id, 'n', false },
})
local highlighter = STHighlighter.active[bufnr]
if not highlighter then
return
end
highlighter:detach(client_id)
if vim.tbl_isempty(highlighter.client_state) then
highlighter:destroy()
end
end
--- Force a refresh of all semantic tokens
---
--- Only has an effect if the buffer is currently active for semantic token
--- highlighting (|vim.lsp.semantic_tokens.start()| has been called for it)
---
---@param bufnr (nil|number) default: current buffer
function M.force_refresh(bufnr)
vim.validate({
bufnr = { bufnr, 'n', true },
})
if bufnr == nil or bufnr == 0 then
bufnr = api.nvim_get_current_buf()
end
local highlighter = STHighlighter.active[bufnr]
if not highlighter then
return
end
highlighter:reset()
highlighter:send_request()
end
--- |lsp-handler| for the method `workspace/semanticTokens/refresh`
---
--- Refresh requests are sent by the server to indicate a project-wide change
--- that requires all tokens to be re-requested by the client. This handler will
--- invalidate the current results of all buffers and automatically kick off a
--- new request for buffers that are displayed in a window. For those that aren't, a
--- the BufWinEnter event should take care of it next time it's displayed.
---
---@see https://microsoft.github.io/language-server-protocol/specifications/specification-current/#semanticTokens_refreshRequest
handlers['workspace/semanticTokens/refresh'] = function(err, _, ctx)
if err then
return vim.NIL
end
for _, bufnr in ipairs(vim.lsp.get_buffers_by_client_id(ctx.client_id)) do
local highlighter = STHighlighter.active[bufnr]
if highlighter and highlighter.client_state[ctx.client_id] then
highlighter:mark_dirty(ctx.client_id)
if not vim.tbl_isempty(vim.fn.win_findbuf(bufnr)) then
highlighter:send_request()
end
end
end
return vim.NIL
end
local namespace = api.nvim_create_namespace('vim_lsp_semantic_tokens')
api.nvim_set_decoration_provider(namespace, {
on_win = function(_, _, bufnr, topline, botline)
local highlighter = STHighlighter.active[bufnr]
if highlighter then
highlighter:on_win(topline, botline)
end
end,
})
--- for testing only! there is no guarantee of API stability with this!
---
---@private
M.__STHighlighter = STHighlighter
return M