Splitting show_tabs_always into show_tabline_buffers and show_tabline_tabs

README.md

@@ -30,13 +30,14 @@ use {
         section_separators = {'', ''},
         component_separators = {'', ''},
         max_bufferline_percent = 66, -- set to nil by default, and it uses vim.o.columns * 2/3
-        show_tabs_always = false, -- this shows tabs only when there are more than one tab or if the first tab is named
         show_devicons = true, -- this shows devicons in buffer section
         show_bufnr = false, -- this appends [bufnr] to buffer section,
         show_filename_only = false, -- shows base filename only instead of relative path in filename
         modified_icon = "+ ", -- change the default modified icon
         modified_italic = false, -- set to true by default; this determines whether the filename turns italic if modified
         show_tabs_only = false, -- this shows only tabs instead of tabs + buffers
+        show_tabline_buffers = 2, -- this shows buffer names (the left section of the tabline) always, when there is more than one buffer, or never
+        show_tabline_tabs = 1, -- this shows tab names (the right section of the tabline) always, when there is more than one or a named tab, or never
       }
     }
     vim.cmd[[
@@ -102,6 +103,14 @@ Show separator after the last buffer or tab (default = false)
 
 Show only tabs instead of tabs + buffers (default = false)
 
+### tabline_show_tabline_buffers
+
+Shows the buffer names (the left section of the tabline) always (2), when there is more than one buffer (1), or never (0) (default = 2)
+
+### tabline_show_tabline_tabs
+
+Shows the tab names (the right section of the tabline) always (2), when there is more than one or a named tab (1), or never (0) (default = 1)
+
 # Lualine tabline support
 
 [`nvim-lualine/lualine.nvim`](https://github.com/nvim-lualine/lualine.nvim) now has buffers and tabs as components.

lua/tabline.lua

@@ -255,11 +255,11 @@ function M.format_tabs(tabs, max_length)
     end
   end
   M.total_tab_length = total_length
-  if M.options.show_tabs_always then
+  if M.options.show_tabline_tabs == 2 then
     line = "%=%#TabLineFill#%999X" .. line
-  elseif #tabs == 1 and tabs[1].name ~= "1 " then
+  elseif M.options.show_tabline_tabs == 1 and #tabs == 1 and tabs[1].name ~= "1 " then
     line = "%=%#TabLineFill#%999X" .. line
-  elseif #tabs > 1 then
+  elseif M.options.show_tabline_tabs == 1 and #tabs > 1 then
     line = "%=%#TabLineFill#%999X" .. line
   else
     line = "%=%#TabLineFill#%999X"
@@ -462,6 +462,13 @@ function M.format_buffers(buffers, max_length)
       end
     end
   end
+
+  if M.options.show_tabline_buffers == 1 and #buffers == 1 then
+    line = "%#tabline_c_normal#"
+  elseif M.options.show_tabline_buffers == 0 then
+    line = "%#tabline_c_normal#"
+  end
+
   return line
 end
 
@@ -810,10 +817,11 @@ function M.setup(opts)
     let g:tabline_show_bufnr = get(g:, "tabline_show_bufnr", v:false)
     let g:tabline_show_filename_only = get(g:, "tabline_show_filename_only", v:false)
     let g:tabline_show_last_separator = get(g:, "tabline_show_last_separator", v:false)
-    let g:tabline_show_tabs_always = get(g:, "tabline_show_tabs_always", v:false)
     let g:tabline_modified_icon = get(g:, "tabline_modified_icon", " ")
     let g:tabline_modified_italic = get(g:, "tabline_modified_italic", v:true)
     let g:tabline_show_tabs_only = get(g:, "tabline_show_tabs_only", v:false)
+    let g:tabline_show_tabline_buffers = get(g:, "tabline_show_tabline_buffers", 2)
+    let g:tabline_show_tabline_tabs = get(g:, "tabline_show_tabline_tabs", 1)
   ]])
 
   if opts == nil then
@@ -865,12 +873,16 @@ function M.setup(opts)
     end
   end
 
-  if opts.options.always_show_tabs ~= nil then
-    M.options.show_tabs_always = opts.options.always_show_tabs
-  elseif opts.options.show_tabs_always ~= nil then
-    M.options.show_tabs_always = opts.options.show_tabs_always
+  if opts.options.show_tabline_tabs ~= nil then
+    M.options.show_tabline_tabs = opts.options.show_tabline_tabs
+  else
+    M.options.show_tabline_tabs = vim.g.tabline_show_tabline_tabs
+  end
+
+  if opts.options.show_tabline_buffers ~= nil then
+    M.options.show_tabline_buffers= opts.options.show_tabline_buffers
   else
-    M.options.show_tabs_always = vim.g.tabline_show_tabs_always
+    M.options.show_tabline_buffers= vim.g.tabline_show_tabline_buffers
   end
 
   if opts.options.show_bufnr ~= nil then
@@ -946,16 +958,58 @@ function M.setup(opts)
   ]])
 
   function _G.tabline_buffers_tabs()
+    local buffers
+    local tabs = M.tabline_tabs(M.options)
     if M.options.show_tabs_only then
-      return M.tabline_buffers_tabs_only(M.options)
+      buffers = M.tabline_buffers_tabs_only(M.options)
+    else
+      buffers = M.tabline_buffers(M.options)
     end
-    local tabs = M.tabline_tabs(M.options)
-    return M.tabline_buffers(M.options) .. tabs
+
+    return buffers .. tabs
+  end
+
+  -- to_delete: the count of buffers to be deleted after this call
+  function _G.update_tabline_visibility(to_delete)
+    local tab_count = vim.fn.tabpagenr('$')
+    local buf_count
+    if M.options.show_tabs_only == false then
+      buf_count = -to_delete
+      for b = 1, vim.fn.bufnr('$') do
+        -- this should be a function (same tests repeated for 4 times...)
+        if vim.fn.buflisted(b) ~= 0 and vim.fn.getbufvar(b, "&buftype") ~= "quickfix" then
+          buf_count = buf_count + 1
+        end
+      end
+    else
+      buf_count = tab_count
+    end
+
+    local function is_shown(opt, count)
+      return opt == 2 or (opt == 1 and count > 1)
+    end
+
+    local v
+    if is_shown(M.options.show_tabline_buffers, buf_count)
+       or is_shown(M.options.show_tabline_tabs, tab_count) then
+      v = 2
+    else
+      v = 0
+    end
+
+    vim.o.showtabline = v
   end
 
   if opts.enable then
     vim.o.tabline = "%!v:lua.tabline_buffers_tabs()"
-    vim.o.showtabline = 2
+    update_tabline_visibility(0)
+    vim.cmd([[
+      augroup TablineUpdateVisibility
+        autocmd!
+        autocmd BufAdd,TabNew,TabClosed * call v:lua.update_tabline_visibility(0)
+        autocmd BufDelete * call v:lua.update_tabline_visibility(1)
+      augroup END
+    ]])
   end
 end