From d845369295b3be51c1fa4679ac9a66b9d514c6aa Mon Sep 17 00:00:00 2001
From: Cameron Ring <cameron@cs.stanford.edu>
Date: Thu, 22 Aug 2024 14:58:16 -0700
Subject: [PATCH] fix: handle symlinks in allowed/suppressed dirs

---
 .gitignore                  |  1 +
 lua/auto-session/lib.lua    | 32 +++++++++++++++++++++++++++-----
 tests/allowed_dirs_spec.lua | 23 +++++++++++++++++++++++
 3 files changed, 51 insertions(+), 5 deletions(-)

diff --git a/.gitignore b/.gitignore
index 77ddff8..50e4407 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ doc/tags
 tests/test_sessions
 tests/custom_sessions
 tests/test_git
+tests/symlink-test
diff --git a/lua/auto-session/lib.lua b/lua/auto-session/lib.lua
index 732bf9c..643b2d4 100644
--- a/lua/auto-session/lib.lua
+++ b/lua/auto-session/lib.lua
@@ -491,12 +491,34 @@ end
 ---@param dirs table
 ---@param dirToFind string
 function Lib.find_matching_directory(dirToFind, dirs)
-  Lib.logger.debug("find_matching_directory", { dirToFind = dirToFind, dirs = dirs })
-  for _, s in pairs(dirs) do
-    local expanded = Lib.expand(s)
-    -- Lib.logger.debug("find_matching_directory expanded: " .. s)
+  local dirsToCheck = {}
+
+  -- resolve any symlinks and also check those
+  for _, dir in pairs(dirs) do
+    -- first expand it
+    local expanded_dir = Lib.expand(dir)
+
+    -- resolve symlinks
+    local resolved_dir = vim.fn.resolve(expanded_dir)
+
+    -- Lib.logger.debug("dir: " .. dir .. " expanded_dir: " .. expanded_dir .. " resolved_dir: " .. resolved_dir)
+
+    -- add the base expanded dir first. in theory, we should only need
+    -- the resolved directory but other systems might behave differently so
+    -- safer to check both
+    table.insert(dirsToCheck, expanded_dir)
+
+    -- add the resolved dir if it's different (e.g. a symlink)
+    if resolved_dir ~= expanded_dir then
+      table.insert(dirsToCheck, resolved_dir)
+    end
+  end
+
+  Lib.logger.debug("find_matching_directory", { dirToFind = dirToFind, dirsToCheck = dirsToCheck })
+
+  for _, dir in pairs(dirsToCheck) do
     ---@diagnostic disable-next-line: param-type-mismatch
-    for path in string.gmatch(expanded, "[^\r\n]+") do
+    for path in string.gmatch(dir, "[^\r\n]+") do
       local simplified_path = vim.fn.simplify(path)
       local path_without_trailing_slashes = string.gsub(simplified_path, "/+$", "")
 
diff --git a/tests/allowed_dirs_spec.lua b/tests/allowed_dirs_spec.lua
index 4389801..293239e 100644
--- a/tests/allowed_dirs_spec.lua
+++ b/tests/allowed_dirs_spec.lua
@@ -7,10 +7,12 @@ describe("The allowed dirs config", function()
   local c = require "auto-session.config"
   as.setup {
     auto_session_allowed_dirs = { "/dummy" },
+    -- log_level = "debug",
   }
 
   TL.clearSessionFilesAndBuffers()
   vim.cmd("e " .. TL.test_file)
+  local cwd = vim.fn.getcwd()
 
   it("doesn't save a session for a non-allowed dir", function()
     as.AutoSaveSession()
@@ -46,4 +48,25 @@ describe("The allowed dirs config", function()
     -- Make sure the session was created
     assert.equals(1, vim.fn.filereadable(session_path))
   end)
+
+  if vim.fn.has "win32" == 0 then
+    it("saves a session for an allowed dir with a symlink", function()
+      TL.clearSessionFilesAndBuffers()
+      vim.cmd("cd " .. cwd)
+
+      vim.cmd("e " .. TL.test_file)
+      c.allowed_dirs = { vim.fn.getcwd() .. "/tests/symlink-test" }
+
+      vim.fn.system "ln -snf test_files tests/symlink-test"
+      vim.cmd "cd tests/symlink-test"
+
+      local session_path = TL.makeSessionPath(vim.fn.getcwd())
+      assert.equals(0, vim.fn.filereadable(session_path))
+
+      assert.True(as.AutoSaveSession())
+
+      -- Make sure the session was created
+      assert.equals(1, vim.fn.filereadable(session_path))
+    end)
+  end
 end)