Improve $GIT_DIR handling

- Retrieve $GIT_DIR using `git rev-parse --absolute-git-dir`
- Move $GIT_DIR ignore in the project exploration part

Resolves #1976

Author: Damien MEHALA

lua/nvim-tree/explorer/explore.lua

@@ -30,7 +30,8 @@ local function populate_children(handle, cwd, node, git_status)
 
     t = get_type_from(t, abs)
     if
-      not filters.should_filter(abs, filter_status)
+      abs ~= git_status.git_dir
+      and not filters.should_filter(abs, filter_status)
       and not nodes_by_path[abs]
       and Watcher.is_fs_event_capable(abs)
     then

lua/nvim-tree/explorer/watch.lua

@@ -4,10 +4,6 @@ local Watcher = require("nvim-tree.watcher").Watcher
 
 local M = {}
 
-local function is_git(path)
-  return vim.fn.fnamemodify(path, ":t") == ".git"
-end
-
 local IGNORED_PATHS = {
   -- disable watchers on kernel filesystems
   -- which have a lot of unwanted events
@@ -44,7 +40,7 @@ function M.create_watcher(node)
     path = node.absolute_path
   end
 
-  if is_git(path) or is_folder_ignored(path) then
+  if is_folder_ignored(path) then
     return nil
   end
 

lua/nvim-tree/git/init.lua

@@ -143,29 +143,36 @@ function M.load_project_status(cwd)
     timeout = M.config.git.timeout,
   }
 
+  local git_directory = git_utils.get_git_directory(project_root)
+
   local watcher = nil
   if M.config.filesystem_watchers.enable then
     log.line("watcher", "git start")
 
-    local callback = function(w)
-      log.line("watcher", "git event scheduled '%s'", w.project_root)
-      utils.debounce("git:watcher:" .. w.project_root, M.config.filesystem_watchers.debounce_delay, function()
-        if w.destroyed then
-          return
-        end
-        reload_tree_at(w.project_root)
-      end)
-    end
+    if git_directory == nil then
+      log.line("watcher", "could not found the location of .git folder")
+    else
+      local callback = function(w)
+        log.line("watcher", "git event scheduled '%s'", w.project_root)
+        utils.debounce("git:watcher:" .. w.project_root, M.config.filesystem_watchers.debounce_delay, function()
+          if w.destroyed then
+            return
+          end
+          reload_tree_at(w.project_root)
+        end)
+      end
 
-    watcher = Watcher:new(utils.path_join { project_root, ".git" }, WATCHED_FILES, callback, {
-      project_root = project_root,
-    })
+      watcher = Watcher:new(git_directory, WATCHED_FILES, callback, {
+        project_root = project_root,
+      })
+    end
   end
 
   M.projects[project_root] = {
     files = git_status,
     dirs = git_utils.file_status_to_dir_status(git_status, project_root),
     watcher = watcher,
+    git_dir = git_directory,
   }
   return M.projects[project_root]
 end

lua/nvim-tree/git/utils.lua

@@ -3,6 +3,22 @@ local log = require "nvim-tree.log"
 
 local has_cygpath = vim.fn.executable "cygpath" == 1
 
+local function norm_path(path)
+  -- git always returns path with forward slashes
+  if vim.fn.has "win32" == 1 then
+    -- msys2 git support
+    if has_cygpath then
+      path = vim.fn.system("cygpath -w " .. vim.fn.shellescape(path))
+      if vim.v.shell_error ~= 0 then
+        return nil
+      end
+    end
+    path = path:gsub("/", "\\")
+  end
+
+  return path
+end
+
 function M.get_toplevel(cwd)
   local profile = log.profile_start("git toplevel %s", cwd)
 
@@ -18,16 +34,9 @@ function M.get_toplevel(cwd)
     return nil
   end
 
-  -- git always returns path with forward slashes
-  if vim.fn.has "win32" == 1 then
-    -- msys2 git support
-    if has_cygpath then
-      toplevel = vim.fn.system("cygpath -w " .. vim.fn.shellescape(toplevel))
-      if vim.v.shell_error ~= 0 then
-        return nil
-      end
-    end
-    toplevel = toplevel:gsub("/", "\\")
+  toplevel = norm_path(toplevel)
+  if toplevel == nil then
+    return nil
   end
 
   -- remove newline
@@ -94,4 +103,28 @@ function M.file_status_to_dir_status(status, cwd)
   return r
 end
 
+function M.get_git_directory(cwd)
+  local profile = log.profile_start("git directory %s", cwd)
+
+  local cmd = { "git", "-C", cwd, "rev-parse", "--absolute-git-dir" }
+  log.line("git", vim.inspect(cmd))
+
+  local git_dir = vim.fn.system(cmd)
+
+  log.raw("git", git_dir)
+  log.profile_end(profile)
+
+  if vim.v.shell_error ~= 0 or not git_dir or #git_dir == 0 or git_dir:match "fatal" then
+    return nil
+  end
+
+  git_dir = norm_path(git_dir)
+  if git_dir == nil then
+    return nil
+  end
+
+  -- remove newline
+  return git_dir:sub(0, -2)
+end
+
 return M