///////////////////////////////////////////////////////
# builtin module may be used implicitly or explicitly #
///////////////////////////////////////////////////////

~> put $true
▶ $true
// regression test for b.elv.sh/1414
~> use builtin
   put $builtin:true
▶ $true

///////////////////////////////////
# builtin functions are read-only #
///////////////////////////////////

~> set return~ = { }
Compilation error: variable $return~ is read-only
  [tty]:1:5-11: set return~ = { }

//////////
# $paths #
//////////

//unset-env PATH

## $E:PATH to $paths ##
~> use path
~> set E:PATH = /bin1$path:list-separator/bin2
~> put $paths
▶ [/bin1 /bin2]

## $paths to $E:PATH ##
~> use path
~> set paths = [/bin1 /bin2]
~> eq $E:PATH /bin1$path:list-separator/bin2
▶ $true

## invalid values ##
~> set paths = [$true]
Exception: path must be string
  [tty]:1:5-9: set paths = [$true]
~> set paths = ["/invalid:;path"]
Exception: path cannot contain NUL byte, colon on Unix or semicolon on Windows
  [tty]:1:5-9: set paths = ["/invalid:;path"]
~> set paths = ["/invalid\000path"]
Exception: path cannot contain NUL byte, colon on Unix or semicolon on Windows
  [tty]:1:5-9: set paths = ["/invalid\000path"]

////////
# $pwd #
////////

//in-temp-dir
~> use os
   use path
// Test both reading and writing $pwd.
~> var start = $pwd
   os:mkdir d
   set pwd = d
   eq $pwd (path:join $start d)
▶ $true

## bad assignment ##
~> set pwd = (num 1)
Exception: path must be string
  [tty]:1:5-7: set pwd = (num 1)

## concrete value (Unix) ##
//only-on unix
~> cd /
   put $pwd
▶ /

## concrete value (Windows) ##
//only-on windows
~> cd C:\
   put $pwd
▶ C:\

## getwd error ##
//mock-getwd-error can't get working directory
~> put $pwd
▶ /unknown/pwd