Add support for custom parser install locations #2959 (#3031)

7 files changed, 136 insertions, 77 deletions

diff --git a/README.md b/README.md
index 13aef22ef..2d77fa246 100644
--- a/README.md
+++ b/README.md
@@ -357,6 +357,38 @@ This will respect your `foldminlines` and `foldnestmax` settings.
 
 # Advanced setup
 
+## Changing the parser install directory
+
+If you want to install the parsers to a custom directory you can specify this
+directory with `parser_install_dir` option in that is passed to `setup`.
+`nvim-treesitter` will then install the parser files into this directory.
+
+This directory must be writeable and must be explicitly added to the
+`runtimepath`. For example:
+
+``` lua
+  require'nvim-treesitter.configs'.setup {
+    parser_install_dir = "/some/path/to/store/parsers",
+
+    ...
+
+  }
+  vim.opt.runtimepath:append("/some/path/to/store/parsers")
+```
+
+If this option is not included in the setup options, or is explicitly set to
+`nil` then the default install directories will be used. If this value is set
+the default directories will be ignored. 
+
+Bear in mind that any parser installed into a parser folder on the runtime path
+will still be considered installed. (For example if
+"~/.local/share/nvim/site/parser/c.so" exists then the "c" parser will be
+considered installed, even though it is not in `parser_install_dir`)
+
+The default paths are:
+1. first the package folder. Where `nvim-treesitter` is installed.
+2. second the site directory. This is the "site" subdirectory of `stdpath("data")`.
+
 ## Adding parsers
 
 If you have a parser that is not on the list of supported languages (either as a repository on Github or in a local directory), you can add it manually for use by `nvim-treesitter` as follows:
diff --git a/doc/nvim-treesitter.txt b/doc/nvim-treesitter.txt
index 52553fb0e..e870ab352 100644
--- a/doc/nvim-treesitter.txt
+++ b/doc/nvim-treesitter.txt
@@ -39,6 +39,12 @@ To enable supported features, put this in your `init.lua` file:
 
 >
   require'nvim-treesitter.configs'.setup {
+    -- A directory to install the parsers into.
+    -- If this is excluded or nil parsers are installed
+    -- to either the package dir, or the "site" dir.
+    -- If a custom path is used (not nil) it must be added to the runtimepath.
+    parser_install_dir = "/some/path/to/store/parsers",
+
     -- A list of parser names, or "all"
     ensure_installed = { "c", "lua", "rust" },
 
@@ -62,6 +68,7 @@ To enable supported features, put this in your `init.lua` file:
       additional_vim_regex_highlighting = false,
     },
   }
+  vim.opt.runtimepath:append("/some/path/to/store/parsers")
 <
 
 See |nvim-treesitter-modules| for a list of all available modules and its options.
diff --git a/lua/nvim-treesitter/configs.lua b/lua/nvim-treesitter/configs.lua
index 5ae702a49..ee01f3ede 100644
--- a/lua/nvim-treesitter/configs.lua
+++ b/lua/nvim-treesitter/configs.lua
@@ -1,4 +1,5 @@
 local api = vim.api
+local luv = vim.loop
 
 local queries = require "nvim-treesitter.query"
 local ts_query = require "vim.treesitter.query"
@@ -14,6 +15,7 @@ local config = {
   ensure_installed = {},
   ignore_install = {},
   update_strategy = "lockfile",
+  parser_install_dir = nil,
 }
 -- List of modules that need to be setup on initialization.
 local queued_modules_defs = {}
@@ -379,6 +381,10 @@ end
 function M.setup(user_data)
   config.modules = vim.tbl_deep_extend("force", config.modules, user_data)
   config.ignore_install = user_data.ignore_install or {}
+  config.parser_install_dir = user_data.parser_install_dir or nil
+  if config.parser_install_dir then
+    config.parser_install_dir = vim.fn.expand(config.parser_install_dir, ":p")
+  end
 
   local ensure_installed = user_data.ensure_installed or {}
   if #ensure_installed > 0 then
@@ -528,6 +534,45 @@ function M.init()
   end
 end
 
+-- If parser_install_dir is not nil is used or created.
+-- If parser_install_dir is nil try the package dir of the nvim-treesitter
+-- plugin first, followed by the "site" dir from "runtimepath". "site" dir will
+-- be created if it doesn't exist. Using only the package dir won't work when
+-- the plugin is installed with Nix, since the "/nix/store" is read-only.
+function M.get_parser_install_dir(folder_name)
+  folder_name = folder_name or "parser"
+
+  if config.parser_install_dir then
+    local parser_dir = utils.join_path(config.parser_install_dir, folder_name)
+    return utils.create_or_resue_writable_dir(
+      parser_dir,
+      utils.join_space("Could not create parser dir '", parser_dir, "': "),
+      utils.join_space("Parser dir '", parser_dir, "' should be read/write.")
+    )
+  end
+
+  local package_path = utils.get_package_path()
+  local package_path_parser_dir = utils.join_path(package_path, folder_name)
+
+  -- If package_path is read/write, use that
+  if luv.fs_access(package_path_parser_dir, "RW") then
+    return package_path_parser_dir
+  end
+
+  local site_dir = utils.get_site_dir()
+  local parser_dir = utils.join_path(site_dir, folder_name)
+
+  return utils.create_or_resue_writable_dir(
+    parser_dir,
+    nil,
+    utils.join_space("Invalid rights,", package_path, "or", parser_dir, "should be read/write")
+  )
+end
+
+function M.get_parser_info_dir(parser_install_dir)
+  return M.get_parser_install_dir "parser-info"
+end
+
 function M.get_update_strategy()
   return config.update_strategy
 end
diff --git a/lua/nvim-treesitter/install.lua b/lua/nvim-treesitter/install.lua
index 10f08dace..822e00e69 100644
--- a/lua/nvim-treesitter/install.lua
+++ b/lua/nvim-treesitter/install.lua
@@ -80,7 +80,7 @@ local function get_revision(lang)
 end
 
 local function get_installed_revision(lang)
-  local lang_file = utils.join_path(utils.get_parser_info_dir(), lang .. ".revision")
+  local lang_file = utils.join_path(configs.get_parser_info_dir(), lang .. ".revision")
   if vim.fn.filereadable(lang_file) == 1 then
     return vim.fn.readfile(lang_file)[1]
   end
@@ -243,9 +243,9 @@ local function run_install(cache_folder, install_folder, lang, repo, with_sync,
     compile_location = repo.url
   else
     local repo_location = string.gsub(repo.location or project_name, "/", path_sep)
-    compile_location = cache_folder .. path_sep .. repo_location
+    compile_location = utils.join_path(cache_folder, repo_location)
   end
-  local parser_lib_name = install_folder .. path_sep .. lang .. ".so"
+  local parser_lib_name = utils.join_path(install_folder, lang) .. ".so"
 
   generate_from_grammar = repo.requires_generate_from_grammar or generate_from_grammar
 
@@ -329,7 +329,7 @@ local function run_install(cache_folder, install_folder, lang, repo, with_sync,
     shell.select_mv_cmd("parser.so", parser_lib_name, compile_location),
     {
       cmd = function()
-        vim.fn.writefile({ revision or "" }, utils.join_path(utils.get_parser_info_dir(), lang .. ".revision"))
+        vim.fn.writefile({ revision or "" }, utils.join_path(configs.get_parser_info_dir(), lang .. ".revision"))
       end,
     },
     { -- auto-attach modules after installation
@@ -392,7 +392,7 @@ local function install(options)
       return api.nvim_err_writeln(err)
     end
 
-    local install_folder, err = utils.get_parser_install_dir()
+    local install_folder, err = configs.get_parser_install_dir()
     if err then
       return api.nvim_err_writeln(err)
     end
@@ -459,11 +459,6 @@ function M.update(options)
 end
 
 function M.uninstall(...)
-  local path_sep = "/"
-  if fn.has "win32" == 1 then
-    path_sep = "\\"
-  end
-
   if vim.tbl_contains({ "all" }, ...) then
     reset_progress_counter()
     local installed = info.installed_parsers()
@@ -473,12 +468,12 @@ function M.uninstall(...)
   elseif ... then
     local languages = vim.tbl_flatten { ... }
     for _, lang in ipairs(languages) do
-      local install_dir, err = utils.get_parser_install_dir()
+      local install_dir, err = configs.get_parser_install_dir()
       if err then
         return api.nvim_err_writeln(err)
       end
 
-      local parser_lib = install_dir .. path_sep .. lang .. ".so"
+      local parser_lib = utils.join_path(install_dir, lang) .. ".so"
 
       local command_list = {
         shell.select_rm_file_cmd(parser_lib, "Uninstalling parser for " .. lang),
diff --git a/lua/nvim-treesitter/shell_command_selectors.lua b/lua/nvim-treesitter/shell_command_selectors.lua
index 0983d850b..522ac727a 100644
--- a/lua/nvim-treesitter/shell_command_selectors.lua
+++ b/lua/nvim-treesitter/shell_command_selectors.lua
@@ -187,7 +187,7 @@ function M.select_download_commands(repo, project_name, cache_folder, revision,
       M.select_install_rm_cmd(cache_folder, project_name .. "-tmp"),
       {
         cmd = "curl",
-        info = "Downloading...",
+        info = "Downloading " .. project_name .. "...",
         err = "Error during download, please verify your internet connection",
         opts = {
           args = {
@@ -204,7 +204,7 @@ function M.select_download_commands(repo, project_name, cache_folder, revision,
       M.select_mkdir_cmd(project_name .. "-tmp", cache_folder, "Creating temporary directory"),
       {
         cmd = "tar",
-        info = "Extracting...",
+        info = "Extracting " .. project_name .. "...",
         err = "Error during tarball extraction.",
         opts = {
           args = {
@@ -231,7 +231,7 @@ function M.select_download_commands(repo, project_name, cache_folder, revision,
     return {
       {
         cmd = "git",
-        info = "Downloading...",
+        info = "Downloading " .. project_name .. "...",
         err = clone_error,
         opts = {
           args = {
diff --git a/lua/nvim-treesitter/utils.lua b/lua/nvim-treesitter/utils.lua
index b64f5b1d9..873c96eae 100644
--- a/lua/nvim-treesitter/utils.lua
+++ b/lua/nvim-treesitter/utils.lua
@@ -10,6 +10,27 @@ function M.notify(msg, log_level, opts)
   vim.notify(msg, log_level, vim.tbl_extend("force", default_opts, opts or {}))
 end
 
+-- Returns the system specific path seperator.
+function M.get_path_sep()
+  return fn.has "win32" == 1 and "\\" or "/"
+end
+
+-- Returns a function that joins the given arguments with separator. Arguments
+-- can't be nil. Example:
+--[[
+print(M.generate_join(" ")("foo", "bar"))
+--]]
+-- prints "foo bar"
+function M.generate_join(separator)
+  return function(...)
+    return table.concat({ ... }, separator)
+  end
+end
+
+M.join_path = M.generate_join(M.get_path_sep())
+
+M.join_space = M.generate_join " "
+
 --- Define user defined vim command which calls nvim-treesitter module function
 ---     - If module name is 'mod', it should be defined in hierarchy 'nvim-treesitter.mod'
 ---     - A table with name 'commands' should be defined in 'mod' which needs to be passed as
@@ -65,25 +86,27 @@ function M.setup_commands(mod, commands)
   end
 end
 
-function M.get_path_sep()
-  return fn.has "win32" == 1 and "\\" or "/"
-end
+function M.create_or_resue_writable_dir(dir, create_err, writeable_err)
+  create_err = create_err or M.join_space("Could not create dir '", dir, "': ")
+  writeable_err = writeable_err or M.join_space("Invalid rights, '", dir, "' should be read/write")
+  -- Try creating and using parser_dir if it doesn't exist
+  if not luv.fs_stat(dir) then
+    local ok, error = pcall(vim.fn.mkdir, dir, "p", "0755")
+    if not ok then
+      return nil, M.join_space(create_err, error)
+    end
 
--- Returns a function that joins the given arguments with separator. Arguments
--- can't be nil. Example:
---[[
-print(M.generate_join(" ")("foo", "bar"))
---]]
--- prints "foo bar"
-function M.generate_join(separator)
-  return function(...)
-    return table.concat({ ... }, separator)
+    return dir
   end
-end
 
-M.join_path = M.generate_join(M.get_path_sep())
+  -- parser_dir exists, use it if it's read/write
+  if luv.fs_access(dir, "RW") then
+    return dir
+  end
 
-local join_space = M.generate_join " "
+  -- parser_dir exists but isn't read/write, give up
+  return nil, M.join_space(writeable_err, dir, "'")
+end
 
 function M.get_package_path()
   -- Path to this source file, removing the leading '@'
@@ -102,56 +125,13 @@ function M.get_cache_dir()
     return "/tmp"
   end
 
-  return nil, join_space("Invalid cache rights,", fn.stdpath "data", "or /tmp should be read/write")
+  return nil, M.join_space("Invalid cache rights,", fn.stdpath "data", "or /tmp should be read/write")
 end
 
 -- Returns $XDG_DATA_HOME/nvim/site, but could use any directory that is in
 -- runtimepath
 function M.get_site_dir()
-  local path_sep = M.get_path_sep()
-  return M.join_path(fn.stdpath "data", path_sep, "site")
-end
-
--- Try the package dir of the nvim-treesitter plugin first, followed by the
--- "site" dir from "runtimepath". "site" dir will be created if it doesn't
--- exist. Using only the package dir won't work when the plugin is installed
--- with Nix, since the "/nix/store" is read-only.
-function M.get_parser_install_dir(folder_name)
-  folder_name = folder_name or "parser"
-  local package_path = M.get_package_path()
-  local package_path_parser_dir = M.join_path(package_path, folder_name)
-
-  -- If package_path is read/write, use that
-  if luv.fs_access(package_path_parser_dir, "RW") then
-    return package_path_parser_dir
-  end
-
-  local site_dir = M.get_site_dir()
-  local path_sep = M.get_path_sep()
-  local parser_dir = M.join_path(site_dir, path_sep, folder_name)
-
-  -- Try creating and using parser_dir if it doesn't exist
-  if not luv.fs_stat(parser_dir) then
-    local ok, error = pcall(vim.fn.mkdir, parser_dir, "p", "0755")
-    if not ok then
-      return nil, join_space("Couldn't create parser dir", parser_dir, ":", error)
-    end
-
-    return parser_dir
-  end
-
-  -- parser_dir exists, use it if it's read/write
-  if luv.fs_access(parser_dir, "RW") then
-    return parser_dir
-  end
-
-  -- package_path isn't read/write, parser_dir exists but isn't read/write
-  -- either, give up
-  return nil, join_space("Invalid cache rights,", package_path, "or", parser_dir, "should be read/write")
-end
-
-function M.get_parser_info_dir()
-  return M.get_parser_install_dir "parser-info"
+  return M.join_path(fn.stdpath "data", "site")
 end
 
 -- Gets a property at path
diff --git a/tests/query/injection_spec.lua b/tests/query/injection_spec.lua
index 7a98dd275..b10b7450f 100644
--- a/tests/query/injection_spec.lua
+++ b/tests/query/injection_spec.lua
@@ -1,6 +1,6 @@
 require "nvim-treesitter.highlight" -- yes, this is necessary to set the hlmap
 local highlighter = require "vim.treesitter.highlighter"
-local utils = require "nvim-treesitter.utils"
+local configs = require "nvim-treesitter.configs"
 local ts_utils = require "nvim-treesitter.ts_utils"
 local parsers = require "nvim-treesitter.parsers"
 
@@ -16,7 +16,7 @@ local function check_assertions(file)
   )
   local assertions = vim.fn.json_decode(
     vim.fn.system(
-      "highlight-assertions -p '" .. utils.get_parser_install_dir() .. "/" .. lang .. ".so'" .. " -s '" .. file .. "'"
+      "highlight-assertions -p '" .. configs.get_parser_install_dir() .. "/" .. lang .. ".so'" .. " -s '" .. file .. "'"
     )
   )
   local parser = parsers.get_parser(buf, lang)