Use table.concat instead of string concatentation (#7)

lua/lualine.lua

@@ -66,33 +66,33 @@ local function StatusLine(isFocused)
     M.theme = utils.setTheme(M.theme)
     highlight.createHighlightGroups(M.theme)
   end
-  local status = ''
+  local status = {}
   if sections.lualine_a ~= nil then
-    status = status .. highlight.formatHighlight(isFocused, 'lualine_a')
-    status = status .. utils.drawSection(sections.lualine_a, M.separator)
+    table.insert(status, highlight.formatHighlight(isFocused, 'lualine_a'))
+    table.insert(status, utils.drawSection(sections.lualine_a, M.separator))
   end
   if sections.lualine_b ~= nil then
-    status = status .. highlight.formatHighlight(isFocused, 'lualine_b')
-    status = status .. utils.drawSection(sections.lualine_b, M.separator)
+    table.insert(status, highlight.formatHighlight(isFocused, 'lualine_b'))
+    table.insert(status, utils.drawSection(sections.lualine_b, M.separator))
   end
   if sections.lualine_c ~= nil then
-    status = status .. highlight.formatHighlight(isFocused, 'lualine_c')
-    status = status .. utils.drawSection(sections.lualine_c, M.separator)
+    table.insert(status, highlight.formatHighlight(isFocused, 'lualine_c'))
+    table.insert(status, utils.drawSection(sections.lualine_c, M.separator))
   end
-  status = status .. [[%=]]
+  table.insert(status, "%=")
   if sections.lualine_x ~= nil then
-    status = status .. highlight.formatHighlight(isFocused, 'lualine_c')
-    status = status .. utils.drawSection(sections.lualine_x, M.separator)
+    table.insert(status, highlight.formatHighlight(isFocused, 'lualine_c'))
+    table.insert(status, utils.drawSection(sections.lualine_x, M.separator))
   end
   if sections.lualine_y ~= nil then
-    status = status .. highlight.formatHighlight(isFocused, 'lualine_b')
-    status = status .. utils.drawSection(sections.lualine_y, M.separator)
+    table.insert(status, highlight.formatHighlight(isFocused, 'lualine_b'))
+    table.insert(status, utils.drawSection(sections.lualine_y, M.separator))
   end
   if sections.lualine_z ~= nil then
-    status = status .. highlight.formatHighlight(isFocused, 'lualine_a')
-    status = status .. utils.drawSection(sections.lualine_z, M.separator)
+    table.insert(status, highlight.formatHighlight(isFocused, 'lualine_a'))
+    table.insert(status, utils.drawSection(sections.lualine_z, M.separator))
   end
-  return status
+  return table.concat(status)
 end
 
 function M.status()

lua/lualine/highlight.lua

@@ -1,27 +1,23 @@
 local M = {  }
 
 local function highlight (name, foreground, background, special)
-  if special == nil then
-    special = 'none'
-  end
-  local command = 'highlight '
-  command = command .. name .. ' '
-  command = command .. 'guifg=' .. foreground .. ' '
-  command = command .. 'guibg=' .. background .. ' '
-  if special then
-    command = command .. 'gui=' .. special .. ' '
-  end
-  return command
+  local command = {
+    'highlight', name,
+    'guifg=' .. foreground,
+    'guibg=' .. background,
+    'gui=' .. (special or 'none'),
+  }
+  return table.concat(command, ' ')
 end
 
 function M.createHighlightGroups(theme)
   for mode, sections in pairs(theme) do
     for section, colorscheme in pairs(sections) do
+      local special = nil
       if section == 'a' then
-        vim.cmd(highlight('lualine_' .. section .. '_' .. mode, colorscheme.fg, colorscheme.bg ,'bold'))
-      else
-        vim.cmd(highlight('lualine_' .. section .. '_' .. mode, colorscheme.fg, colorscheme.bg ))
+        special = 'bold'
       end
+      vim.cmd(highlight('lualine_' .. section .. '_' .. mode, colorscheme.fg, colorscheme.bg, special))
     end
   end
 end

lua/lualine/utils.lua

@@ -5,29 +5,21 @@ function M.setTheme(theme)
 end
 
 function M.drawSection(section, separator)
-  local status = ''
-  for index, statusFunction in pairs(section) do
+  local status = {}
+  for _, statusFunction in pairs(section) do
     local localstatus = statusFunction()
-    if localstatus:len() > 0 then
-      if separator:len() > 0 then
-        if index > 1 then
-          status = status .. separator .. ' '
-        end
-        status = status .. localstatus
-        status = status .. ' '
-      else
-        status = status .. localstatus
-        status = status .. ' '
-      end
+    if #localstatus > 0 then
+      table.insert(status, localstatus)
     end
   end
-  if status:len() > 0 then
-    if separator:len() > 0 and table.maxn(section) > 1 then
-      return ' ' .. status .. ' '
-    end
-    return ' ' .. status
+  if #status == 0 then
+    return ''
   end
-  return ''
+  local sep = ' '
+  if #separator > 0 then
+    sep = ' ' .. separator .. ' '
+  end
+  return ' ' .. table.concat(status, sep) .. ' '
 end
 
 return M