add used_by key to parsers

Enables the use of multiple filetypes for one parser.

lua/nvim-treesitter.lua

@@ -17,9 +17,10 @@ function M.setup()
   for _, lang in pairs(parsers.available_parsers()) do
     for _, mod in pairs(configs.available_modules()) do
       if configs.is_enabled(mod, lang) then
-        local ft = parsers.lang_to_ft(lang)
         local cmd = string.format("lua require'nvim-treesitter.%s'.attach()", mod)
-        api.nvim_command(string.format("autocmd NvimTreesitter FileType %s %s", ft, cmd))
+        for _, ft in pairs(parsers.lang_to_ft(lang)) do
+          api.nvim_command(string.format("autocmd NvimTreesitter FileType %s %s", ft, cmd))
+        end
       end
     end
   end

lua/nvim-treesitter/configs.lua

@@ -49,9 +49,10 @@ end
 local function enable_mod_conf_autocmd(mod, lang)
   if not config.modules[mod] or M.is_enabled(mod, lang) then return end
 
-  local ft = parsers.lang_to_ft(lang)
   local cmd = string.format("lua require'nvim-treesitter.%s'.attach()", mod)
-  api.nvim_command(string.format("autocmd FileType %s %s", ft, cmd))
+  for _, ft in pairs(parsers.lang_to_ft(lang)) do
+    api.nvim_command(string.format("autocmd NvimTreesitter FileType %s %s", ft, cmd))
+  end
   for i, parser in pairs(config.modules[mod].disable) do
     if parser == lang then
       table.remove(config.modules[mod].disable, i)
@@ -65,7 +66,7 @@ local function enable_all(mod, lang)
 
   for _, bufnr in pairs(api.nvim_list_bufs()) do
     local ft = api.nvim_buf_get_option(bufnr, 'ft')
-    if not lang or ft == parsers.lang_to_ft(lang) then
+    if not lang or parsers.lang_match_ft(lang, ft) then
       enable_module(mod, bufnr, lang)
     end
   end
@@ -101,15 +102,18 @@ end
 local function disable_mod_conf_autocmd(mod, lang)
   if not config.modules[mod] or not M.is_enabled(mod, lang) then return end
 
-  local ft = parsers.lang_to_ft(lang)
-  api.nvim_command(string.format("autocmd! FileType %s", ft))
+  local cmd = string.format("lua require'nvim-treesitter.%s'.attach()", mod)
+  -- TODO(kyazdani): detach the correct autocmd... doesn't work when using %s, cmd
+  for _, ft in pairs(parsers.lang_to_ft(lang)) do
+    api.nvim_command(string.format("autocmd! NvimTreesitter FileType %s", ft))
+  end
   table.insert(config.modules[mod].disable, lang)
 end
 
 local function disable_all(mod, lang)
   for _, bufnr in pairs(api.nvim_list_bufs()) do
     local ft = api.nvim_buf_get_option(bufnr, 'ft')
-    if not lang or ft == parsers.lang_to_ft(lang) then
+    if not lang or parsers.lang_match_ft(lang, ft) then
       disable_module(mod, bufnr, lang)
     end
   end

lua/nvim-treesitter/parsers.lua

@@ -64,6 +64,7 @@ list.bash = {
     url = "https://github.com/tree-sitter/tree-sitter-bash",
     files = { "src/parser.c", "src/scanner.cc" },
   },
+  used_by = { "zsh" },
   filetype = 'sh'
 }
 
@@ -205,10 +206,10 @@ list.nix = {
 }
 
 list.regex = {
-    install_info = {
-        url = "https://github.com/tree-sitter/tree-sitter-regex",
-        files = { "src/parser.c" }
-    }
+  install_info = {
+    url = "https://github.com/tree-sitter/tree-sitter-regex",
+    files = { "src/parser.c" }
+  }
 }
 
 local M = {
@@ -216,12 +217,14 @@ local M = {
 }
 
 local ft_to_parsername = {}
+
 for name, obj in pairs(M.list) do
-  if obj.filetype then
-    ft_to_parsername[obj.filetype] = name
-  else
-    ft_to_parsername[name] = name
+  if type(obj.used_by) == 'table' then
+    for _, ft in pairs(obj.used_by) do
+      ft_to_parsername[ft] = name
+    end
   end
+  ft_to_parsername[obj.filetype or name] = name
 end
 
 function M.ft_to_lang(ft)
@@ -229,7 +232,17 @@ function M.ft_to_lang(ft)
 end
 
 function M.lang_to_ft(lang)
-  return M.list[lang].filetype or lang
+  local obj = M.list[lang]
+  return vim.tbl_flatten({{obj.filetype or lang}, obj.used_by or {}})
+end
+
+function M.lang_match_ft(lang, ft)
+  for _, f in pairs(M.lang_to_ft(lang)) do
+    if ft == f then
+      return true
+    end
+  end
+  return false
 end
 
 function M.available_parsers()