Ignore warnings from compdb in :BuildDir

lua/build.lua

@@ -34,8 +34,19 @@ function build.set_dir(dirname)
     local compile_commands = current_dir .. '/compile_commands.json'
     local output = vim.fn.systemlist(
       'compdb -p ' .. build.dir .. ' list > ' .. compile_commands)
-    if table.maxn(output) > 0 then
+
-      echo(vim.fn.join(output, '\n'), 'Error')
+    -- Remove any lines containing a compdb warning
+    local error = {}
+    local warning = 'WARNING:compdb'
+    for _, line in ipairs(output) do
+      if string.sub(line, 1, #warning) ~= warning then
+        table.insert(error, line)
+      end
+    end
+
+    -- Display the error message if there was one
+    if table.maxn(error) > 0 then
+      echo(vim.fn.join(error, '\n'), 'Error')
       return
     end