feat(lsp): add function to clear codelens (#21504)

Currently once you retrieve the lenses you're pretty much stuck with
them as saving new lenses is additive.

Adding a dedicated method to reset lenses allows users to toggle lenses
on/off which can be useful for language servers where they are noisy or
expensive and you only want to see them temporary.

runtime/doc/lsp.txt

@@ -1278,6 +1278,13 @@ on_publish_diagnostics({_}, {result}, {ctx}, {config})
 ==============================================================================
 Lua module: vim.lsp.codelens                                    *lsp-codelens*
 
+clear({client_id}, {bufnr})                         *vim.lsp.codelens.clear()*
+    Clear the lenses
+
+    Parameters: ~
+      • {client_id}  (number|nil) filter by client_id. All clients if nil
+      • {bufnr}      (number|nil) filter by buffer. All buffers if nil
+
 display({lenses}, {bufnr}, {client_id})           *vim.lsp.codelens.display()*
     Display the lenses using virtual text
 

runtime/doc/news.txt

@@ -39,6 +39,8 @@ NEW FEATURES                                                    *news-features*
 
 The following new APIs or features were added.
 
+• Added a |vim.lsp.codelens.clear()| function to clear codelenses.
+
 • |vim.inspect_pos()|, |vim.show_pos()| and |:Inspect| allow a user to get or show items
   at a given buffer postion. Currently this includes treesitter captures,
   semantic tokens, syntax groups and extmarks.

runtime/lua/vim/lsp/codelens.lua

@@ -108,13 +108,36 @@ function M.run()
   end
 end
 
+---@private
+local function resolve_bufnr(bufnr)
+  return bufnr == 0 and api.nvim_get_current_buf() or bufnr
+end
+
+--- Clear the lenses
+---
+---@param client_id number|nil filter by client_id. All clients if nil
+---@param bufnr number|nil filter by buffer. All buffers if nil
+function M.clear(client_id, bufnr)
+  local buffers = bufnr and { resolve_bufnr(bufnr) } or vim.tbl_keys(lens_cache_by_buf)
+  for _, iter_bufnr in pairs(buffers) do
+    local client_ids = client_id and { client_id } or vim.tbl_keys(namespaces)
+    for _, iter_client_id in pairs(client_ids) do
+      local ns = namespaces[iter_client_id]
+      lens_cache_by_buf[iter_bufnr][iter_client_id] = {}
+      api.nvim_buf_clear_namespace(iter_bufnr, ns, 0, -1)
+    end
+  end
+end
+
 --- Display the lenses using virtual text
 ---
 ---@param lenses table of lenses to display (`CodeLens[] | null`)
 ---@param bufnr number
 ---@param client_id number
 function M.display(lenses, bufnr, client_id)
+  local ns = namespaces[client_id]
   if not lenses or not next(lenses) then
+    api.nvim_buf_clear_namespace(bufnr, ns, 0, -1)
     return
   end
   local lenses_by_lnum = {}
@@ -126,7 +149,6 @@ function M.display(lenses, bufnr, client_id)
     end
     table.insert(line_lenses, lens)
   end
-  local ns = namespaces[client_id]
   local num_lines = api.nvim_buf_line_count(bufnr)
   for i = 0, num_lines do
     local line_lenses = lenses_by_lnum[i] or {}

test/functional/plugin/lsp/codelens_spec.lua

@@ -58,6 +58,41 @@ describe('vim.lsp.codelens', function()
     ]], bufnr)
 
     eq({[1] = {'Lens1', 'LspCodeLens'}}, virtual_text_chunks)
+  end)
 
+  it('can clear all lens', function()
+    local fake_uri = "file:///fake/uri"
+    local bufnr = exec_lua([[
+      fake_uri = ...
+      local bufnr = vim.uri_to_bufnr(fake_uri)
+      local lines = {'So', 'many', 'lines'}
+      vim.fn.bufload(bufnr)
+      vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
+      return bufnr
+    ]], fake_uri)
+
+    exec_lua([[
+      local bufnr = ...
+      local lenses = {
+        {
+          range = {
+            start = { line = 0, character = 0, },
+            ['end'] = { line = 0, character = 0 }
+          },
+          command = { title = 'Lens1', command = 'Dummy' }
+        },
+      }
+      vim.lsp.codelens.on_codelens(nil, lenses, {method='textDocument/codeLens', client_id=1, bufnr=bufnr})
+    ]], bufnr)
+
+    local stored_lenses = exec_lua('return vim.lsp.codelens.get(...)', bufnr)
+    eq(1, #stored_lenses)
+
+    exec_lua([[
+      vim.lsp.codelens.clear()
+    ]])
+
+    stored_lenses = exec_lua('return vim.lsp.codelens.get(...)', bufnr)
+    eq(0, #stored_lenses)
   end)
 end)