[Refactor/Bugfix] Improve null ls handler (#1277)

1 files changed, 79 insertions, 0 deletions

diff --git a/lua/lsp/null-ls/formatters.lua b/lua/lsp/null-ls/formatters.lua
new file mode 100644
index 00000000..dd88fa60
--- /dev/null
+++ b/lua/lsp/null-ls/formatters.lua
@@ -0,0 +1,79 @@
+local M = {}
+local formatters_by_ft = {}
+
+local null_ls = require "null-ls"
+local services = require "lsp.null-ls.services"
+local logger = require("core.log"):get_default()
+
+local function list_names(formatters, options)
+  options = options or {}
+  local names = {}
+
+  local filter = options.filter or "supported"
+  for name, _ in pairs(formatters[filter]) do
+    table.insert(names, name)
+  end
+
+  return names
+end
+
+function M.list_supported_names(filetype)
+  if not formatters_by_ft[filetype] then
+    return {}
+  end
+  return list_names(formatters_by_ft[filetype], { filter = "supported" })
+end
+
+function M.list_unsupported_names(filetype)
+  if not formatters_by_ft[filetype] then
+    return {}
+  end
+  return list_names(formatters_by_ft[filetype], { filter = "unsupported" })
+end
+
+function M.list_available(filetype)
+  local formatters = {}
+  for _, provider in pairs(null_ls.builtins.formatting) do
+    -- TODO: Add support for wildcard filetypes
+    if vim.tbl_contains(provider.filetypes or {}, filetype) then
+      table.insert(formatters, provider.name)
+    end
+  end
+
+  return formatters
+end
+
+function M.list_configured(formatter_configs)
+  local formatters, errors = {}, {}
+
+  for _, fmt_config in ipairs(formatter_configs) do
+    local formatter = null_ls.builtins.formatting[fmt_config.exe]
+
+    if not formatter then
+      logger.error("Not a valid formatter:", fmt_config.exe)
+      errors[fmt_config.exe] = {} -- Add data here when necessary
+    else
+      local formatter_cmd = services.find_command(formatter._opts.command)
+      if not formatter_cmd then
+        logger.warn("Not found:", formatter._opts.command)
+        errors[fmt_config.exe] = {} -- Add data here when necessary
+      else
+        logger.info("Using formatter:", formatter_cmd)
+        formatters[fmt_config.exe] = formatter.with { command = formatter_cmd, args = fmt_config.args }
+      end
+    end
+  end
+
+  return { supported = formatters, unsupported = errors }
+end
+
+function M.setup(filetype, options)
+  if formatters_by_ft[filetype] and not options.force_reload then
+    return
+  end
+
+  formatters_by_ft[filetype] = M.list_configured(lvim.lang[filetype].formatters)
+  null_ls.register { sources = formatters_by_ft[filetype].supported }
+end
+
+return M