treesitter: simplify query reading logic

Only the plugin/package manager should "manage" after/. Consumers of
nvim_get_runtime_file() should not need to special case it (if your plugin
manager is broken then fix it instead).

Don't use vim.fn.readfile(). Lua can already read files. It is even
better at it than vim script.

expose M.get_query_files(). Listing the queries is essential for user
config debug, and let plugins do fun things with it.
Abstraction-by-obscurity is not useful (plugins can just cargo cult copy
the code anyway, better with public entry points).

1 files changed, 10 insertions, 36 deletions

diff --git a/runtime/lua/vim/treesitter/query.lua b/runtime/lua/vim/treesitter/query.lua
index 682f981fbc..5a27d740a2 100644
--- a/runtime/lua/vim/treesitter/query.lua
+++ b/runtime/lua/vim/treesitter/query.lua
@@ -8,36 +8,10 @@ Query.__index = Query
 
 local M = {}
 
--- Filter the runtime query files, the spec is like regular runtime files but in the new `queries`
--- directory. They resemble ftplugins, that is that you can override queries by adding things in the
--- `queries` directory, and extend using the `after/queries` directory.
-local function filter_files(file_list)
-  local main = nil
-  local after = {}
-
-  for _, fname in ipairs(file_list) do
-    -- Only get the name of the directory containing the queries directory
-    if vim.fn.fnamemodify(fname, ":p:h:h:h:t") == "after" then
-      table.insert(after, fname)
-    -- The first one is the one with most priority
-    elseif not main then
-      main = fname
-    end
-  end
-
-  return main and { main, unpack(after) } or after
-end
-
-local function runtime_query_path(lang, query_name)
-  return string.format('queries/%s/%s.scm', lang, query_name)
-end
-
-local function filtered_runtime_queries(lang, query_name)
-  return filter_files(a.nvim_get_runtime_file(runtime_query_path(lang, query_name), true) or {})
-end
 
-local function get_query_files(lang, query_name, is_included)
-  local lang_files = filtered_runtime_queries(lang, query_name)
+function M.get_query_files(lang, query_name, is_included)
+  local query_path = string.format('queries/%s/%s.scm', lang, query_name)
+  local lang_files = a.nvim_get_runtime_file(query_path, true)
 
   if #lang_files == 0 then return {} end
 
@@ -51,10 +25,10 @@ local function get_query_files(lang, query_name, is_included)
   local MODELINE_FORMAT = "^;+%s*inherits%s*:?%s*([a-z_,()]+)%s*$"
 
   for _, file in ipairs(lang_files) do
-    local modeline = vim.fn.readfile(file, "", 1)
+    local modeline = io.open(file, 'r'):read('*l')
 
-    if #modeline == 1 then
-      local langlist = modeline[1]:match(MODELINE_FORMAT)
+    if modeline then
+      local langlist = modeline:match(MODELINE_FORMAT)
 
       if langlist then
         for _, incllang in ipairs(vim.split(langlist, ',', true)) do
@@ -74,7 +48,7 @@ local function get_query_files(lang, query_name, is_included)
 
   local query_files = {}
   for _, base_lang in ipairs(base_langs) do
-    local base_files = get_query_files(base_lang, query_name, true)
+    local base_files = M.get_query_files(base_lang, query_name, true)
     vim.list_extend(query_files, base_files)
   end
   vim.list_extend(query_files, lang_files)
@@ -86,10 +60,10 @@ local function read_query_files(filenames)
   local contents = {}
 
   for _,filename in ipairs(filenames) do
-    vim.list_extend(contents, vim.fn.readfile(filename))
+    table.insert(contents, io.open(filename, 'r'):read('*a'))
   end
 
-  return table.concat(contents, '\n')
+  return table.concat(contents, '')
 end
 
 local match_metatable = {
@@ -110,7 +84,7 @@ end
 --
 -- @return The corresponding query, parsed.
 function M.get_query(lang, query_name)
-  local query_files = get_query_files(lang, query_name)
+  local query_files = M.get_query_files(lang, query_name)
   local query_string = read_query_files(query_files)
 
   if #query_string > 0 then