fix(lsp): delete bufvar inside WinClosed event

Problem: floaing preview window can be closed by some
ex commands like `only` `fclose` which will not clean the bufvar

Solution: use WinClosed event with floating_winnr for clean
bufnr, and add test cases for vim.lsp.util.open_floating_preview

1 files changed, 34 insertions, 0 deletions

diff --git a/test/functional/plugin/lsp/utils_spec.lua b/test/functional/plugin/lsp/utils_spec.lua
index 813b8de812..ce6e6b2535 100644
--- a/test/functional/plugin/lsp/utils_spec.lua
+++ b/test/functional/plugin/lsp/utils_spec.lua
@@ -5,6 +5,8 @@ local Screen = require('test.functional.ui.screen')
 local feed = n.feed
 local eq = t.eq
 local exec_lua = n.exec_lua
+local command, api = n.command, n.api
+local pcall_err = t.pcall_err
 
 describe('vim.lsp.util', function()
   before_each(n.clear)
@@ -265,6 +267,38 @@ describe('vim.lsp.util', function()
 
         eq(56, opts.height)
       end)
+
+      describe('vim.lsp.util.open_floating_preview', function()
+        local var_name = 'lsp_floating_preview'
+        local curbuf = api.nvim_get_current_buf()
+
+        it('clean bufvar after fclose', function()
+          exec_lua(function()
+            vim.lsp.util.open_floating_preview({ 'test' }, '', { height = 5, width = 2 })
+          end)
+          eq(true, api.nvim_win_is_valid(api.nvim_buf_get_var(curbuf, var_name)))
+          command('fclose')
+          eq(
+            'Key not found: lsp_floating_preview',
+            pcall_err(api.nvim_buf_get_var, curbuf, var_name)
+          )
+        end)
+
+        it('clean bufvar after CursorMoved', function()
+          local result = exec_lua(function()
+            vim.lsp.util.open_floating_preview({ 'test' }, '', { height = 5, width = 2 })
+            local winnr = vim.b[vim.api.nvim_get_current_buf()].lsp_floating_preview
+            local result = vim.api.nvim_win_is_valid(winnr)
+            vim.api.nvim_feedkeys(vim.keycode('G'), 'txn', false)
+            return result
+          end)
+          eq(true, result)
+          eq(
+            'Key not found: lsp_floating_preview',
+            pcall_err(api.nvim_buf_get_var, curbuf, var_name)
+          )
+        end)
+      end)
     end)
   end)
 end)