Each event triggers auto-command at least once - is it the intended behavior?

Lua
1

Suppose, init.lua contains the following:

vim.g.test_var1 = 0
vim.g.test_var2 = 0
vim.g.test_var3 = 0

local aug_test = vim.api.nvim_create_augroup('AuEnv', {clear=true})

-- test_var1 is incremented by 1 when switching between two windows
-- (or between a currently displayed buffer and a hidden one)
vim.api.nvim_create_autocmd('BufEnter,WinEnter', {
  callback = function ()
    -- print('test_var1', vim.g.test_var1)
    vim.g.test_var1 = vim.g.test_var1 + 1
  end,
  group = aug_test,
})

-- test_var2 is incremented by 2 when switching between two windows.
vim.api.nvim_create_autocmd({'BufEnter', 'WinEnter'}, {
  callback = function ()
    -- print('test_var2', vim.g.test_var2)
    vim.g.test_var2 = vim.g.test_var2 + 1
  end,
  group = aug_test,
})


-- test_var3 is incremented by 2 when switching between two buffers.
-- :e some_buf
-- :e another_buf
-- <C-6>
vim.api.nvim_create_autocmd({'BufEnter', 'BufWinEnter'}, {
  callback = function ()
    -- print('test_var3', vim.g.test_var3)
    vim.g.test_var3 = vim.g.test_var3 + 1
  end,
  group = aug_test,
})

If we open at least two buffers (in split - testing var1 and var2, or ‘one active/one hidden’ - testing var2 and var3) and start switching from one window to another or from one buffer to another, and then type :echo test_var1 test_var2 test_var3, they all will have different values, but what is interesting is that test_var1 and test_var2 do. Though, in the both cases, the same events are specified: for test_var1, it is 'BufEnter,WinEnter', whereas, for test_var2 – {'BufEnter', 'WinEnter'}. That is, specifying events as a table will lead to double execution of autocmd when two of the events are valid.

Is it intended behavior? If it is, how can I make it so that an autocmd executes just once if both events come

2

In the first case, BufEnter,WinEnter is equivalent to BufEnter. ,WinEnter is ignored.

3

Ok, correct. It is ignored. But the main point is that {'BufEnter', 'WinEnter'} triggers the execution of my autocmd twice. I want it to be this way “run this function on one of the events, either BufEnter OR WinEnter”. An autocmd might be heavy, I want to avoid its double execution