-- testes/lush/builtins.lua
-- Tests for shell builtins (issue #15): cd, exec, umask.

print "testing shell builtins"

local interp = require("lush.testutil").INTERP

-- === __builtins is NOT in _G (internal, stored in registry) ===

do
  assert(__builtins == nil, "__builtins should not be in _G")
end


-- === cd ===

-- cd to absolute path
do
  local before = `pwd`.stdout:gsub("\n$", "")
  local r = `cd /tmp`
  assert(r.code == 0, "cd /tmp failed: " .. r.stderr)
  local after = `pwd`.stdout:gsub("\n$", "")
  assert(after == "/private/tmp" or after == "/tmp",
         "expected /tmp, got: " .. after)
  `cd ${before}`
end

-- cd with no arg goes to $HOME
do
  local before = `pwd`.stdout:gsub("\n$", "")
  local home = os.getenv("HOME")
  local r = `cd`
  assert(r.code == 0, "cd (no arg) failed: " .. r.stderr)
  local after = `pwd`.stdout:gsub("\n$", "")
  assert(after == home, "expected HOME=" .. home .. ", got: " .. after)
  `cd ${before}`
end

-- cd - goes to OLDPWD
do
  local start = `pwd`.stdout:gsub("\n$", "")
  `cd /tmp`
  local r = `cd -`
  assert(r.code == 0, "cd - failed: " .. r.stderr)
  local after = `pwd`.stdout:gsub("\n$", "")
  assert(after == start, "expected " .. start .. ", got: " .. after)
  `cd ${start}`
end

-- cd updates $PWD and $OLDPWD
do
  local before = `pwd`.stdout:gsub("\n$", "")
  `cd /tmp`
  local pwd = os.getenv("PWD")
  local oldpwd = os.getenv("OLDPWD")
  assert(pwd == "/private/tmp" or pwd == "/tmp",
         "PWD not updated: " .. tostring(pwd))
  assert(oldpwd == before,
         "OLDPWD not updated: expected " .. before .. ", got: " .. tostring(oldpwd))
  `cd ${before}`
end

-- cd to nonexistent directory returns error
do
  local r = `cd /nonexistent_dir_xyz_999`
  assert(r.code == 1)
  assert(r.stderr:find("cd:"), "expected cd error, got: " .. r.stderr)
end

-- cd to relative path
do
  local before = `pwd`.stdout:gsub("\n$", "")
  `cd /tmp`
  os.execute("mkdir -p /tmp/_lush_test_cd")
  local r = `cd _lush_test_cd`
  assert(r.code == 0, "cd relative failed: " .. r.stderr)
  local after = `pwd`.stdout:gsub("\n$", "")
  assert(after:find("_lush_test_cd"),
         "expected to be in _lush_test_cd, got: " .. after)
  `cd ${before}`
  os.execute("rmdir /tmp/_lush_test_cd")
end


-- === umask ===

-- query umask (no arg)
do
  local r = `umask`
  assert(r.code == 0, "umask query failed: " .. r.stderr)
  assert(r.stdout:match("^%d+"), "expected octal, got: " .. r.stdout)
end

-- set and restore umask
do
  local orig = `umask`.stdout:gsub("%s+$", "")
  local r = `umask 0077`
  assert(r.code == 0, "umask set failed: " .. r.stderr)
  local now = `umask`.stdout:gsub("%s+$", "")
  assert(now == "0077", "expected 0077, got: " .. now)
  -- restore original
  `umask ${orig}`
  local restored = `umask`.stdout:gsub("%s+$", "")
  assert(restored == orig,
         "expected " .. orig .. ", got: " .. restored)
end

-- invalid octal
do
  local r = `umask banana`
  assert(r.code == 1)
  assert(r.stderr:find("invalid mode"),
         "expected 'invalid mode', got: " .. r.stderr)
end


-- === exec ===

-- exec with no command returns error (tested via backtick)
do
  local r = `exec`
  assert(r.code == 1)
  assert(r.stderr:find("command required"),
         "expected 'command required', got: " .. r.stderr)
end

-- exec nonexistent command returns error
do
  local r = `exec nonexistent_cmd_xyz_999`
  assert(r.code == 1)
  assert(r.stderr:find("exec:"),
         "expected exec error, got: " .. r.stderr)
end

-- exec replaces process (test in subprocess)
do
  local r = lush.capture("sh -c '" .. interp .. " -e \"os.exit(42)\"'")
  assert(r.code == 42, "subprocess exit code: " .. tostring(r.code))
end


print "OK"