fix(lsp): check if the buffer is a directory before w! it (#22289)

2 files changed, 33 insertions, 3 deletions

diff --git a/runtime/lua/vim/lsp/util.lua b/runtime/lua/vim/lsp/util.lua
index 38051e6410..4beb4fc367 100644
--- a/runtime/lua/vim/lsp/util.lua
+++ b/runtime/lua/vim/lsp/util.lua
@@ -759,9 +759,11 @@ function M.rename(old_fname, new_fname, opts)
   vim.fn.bufload(oldbuf)
 
   -- The there may be pending changes in the buffer
-  api.nvim_buf_call(oldbuf, function()
-    vim.cmd('w!')
-  end)
+  if vim.fn.isdirectory(old_fname) == 0 then
+    api.nvim_buf_call(oldbuf, function()
+      vim.cmd('w!')
+    end)
+  end
 
   local ok, err = os.rename(old_fname, new_fname)
   assert(ok, err)
diff --git a/test/functional/plugin/lsp_spec.lua b/test/functional/plugin/lsp_spec.lua
index fd162961ff..f1aad08140 100644
--- a/test/functional/plugin/lsp_spec.lua
+++ b/test/functional/plugin/lsp_spec.lua
@@ -2067,6 +2067,8 @@ describe('LSP', function()
   end)
 
   describe('lsp.util.rename', function()
+    local pathsep = helpers.get_pathsep()
+
     it('Can rename an existing file', function()
       local old = helpers.tmpname()
       write_file(old, 'Test content')
@@ -2089,6 +2091,32 @@ describe('LSP', function()
       eq(true, exists)
       os.remove(new)
     end)
+    it('Can rename a direcory', function()
+      -- only reserve the name, file must not exist for the test scenario
+      local old_dir = helpers.tmpname()
+      local new_dir = helpers.tmpname()
+      os.remove(old_dir)
+      os.remove(new_dir)
+
+      helpers.mkdir_p(old_dir)
+
+      local file = "file"
+      write_file(old_dir .. pathsep .. file, 'Test content')
+
+      exec_lua([[
+        local old_dir = select(1, ...)
+        local new_dir = select(2, ...)
+
+        vim.lsp.util.rename(old_dir, new_dir)
+      ]], old_dir, new_dir)
+
+      eq(false, exec_lua('return vim.loop.fs_stat(...) ~= nil', old_dir))
+      eq(true, exec_lua('return vim.loop.fs_stat(...) ~= nil', new_dir))
+      eq(true, exec_lua('return vim.loop.fs_stat(...) ~= nil', new_dir .. pathsep .. file))
+      eq('Test content', read_file(new_dir .. pathsep .. file))
+
+      os.remove(new_dir)
+    end)
     it('Does not rename file if target exists and ignoreIfExists is set or overwrite is false', function()
       local old = helpers.tmpname()
       write_file(old, 'Old File')