print("testing functions and calls")

local debug = require "debug"

-- get the opportunity to test 'type' too ;)

assert(type(1<2) == 'boolean')
assert(type(true) == 'boolean' and type(false) == 'boolean')
assert(type(nil) == 'nil' and type(-3) == 'number' and type'x' == 'string' and
       type{} == 'table' and type(type) == 'function')

assert(type(assert) == type(print))
f = nil
function f (x) return a:x (x) end
assert(type(f) == 'function')


-- testing local-function recursion
fact = false
do
  local res = 1
  local function fact (n)
    if n==0 then return res
    else return n*fact(n-1)
    end
  end
  assert(fact(5) == 120)
end
assert(fact == false)

-- testing declarations
a = {i = 10}
self = 20
function a:x (x) return x+self.i end
function a.y (x) return x+self end

assert(a:x(1)+10 == a.y(1))

a.t = {i=-100}
a["t"].x = function (self, a,b) return self.i+a+b end

assert(a.t:x(2,3) == -95)

do
  local a = {x=0}
  function a:add (x) self.x, a.y = self.x+x, 20; return self end
  assert(a:add(10):add(20):add(30).x == 60 and a.y == 20)
end

local a = {b={c={}}}

function a.b.c.f1 (x) return x+1 end
function a.b.c:f2 (x,y) self[x] = y end
assert(a.b.c.f1(4) == 5)
a.b.c:f2('k', 12); assert(a.b.c.k == 12)

print('+')

t = nil   -- 'declare' t
function f(a,b,c) local d = 'a'; t={a,b,c,d} end

f(      -- this line change must be valid
  1,2)
assert(t[1] == 1 and t[2] == 2 and t[3] == nil and t[4] == 'a')
f(1,2,   -- this one too
      3,4)
assert(t[1] == 1 and t[2] == 2 and t[3] == 3 and t[4] == 'a')

function fat(x)
  if x <= 1 then return 1
  else return x*load("return fat(" .. x-1 .. ")")()
  end
end

assert(load "load 'assert(fat(6)==720)' () ")()
a = load('return fat(5), 3')
a,b = a()
assert(a == 120 and b == 3)
print('+')

function err_on_n (n)
  if n==0 then error(); exit(1);
  else err_on_n (n-1); exit(1);
  end
end

do
  function dummy (n)
    if n > 0 then
      assert(not pcall(err_on_n, n))
      dummy(n-1)
    end
  end
end

dummy(10)

function deep (n)
  if n>0 then deep(n-1) end
end
deep(10)
deep(200)

-- testing tail call
function deep (n) if n>0 then return deep(n-1) else return 101 end end
assert(deep(30000) == 101)
a = {}
function a:deep (n) if n>0 then return self:deep(n-1) else return 101 end end
assert(a:deep(30000) == 101)

print('+')


a = nil
(function (x) a=x end)(23)
assert(a == 23 and (function (x) return x*2 end)(20) == 40)


-- testing closures

-- fixed-point operator
Z = function (le)
      local function a (f)
        return le(function (x) return f(f)(x) end)
      end
      return a(a)
    end


-- non-recursive factorial

F = function (f)
      return function (n)
               if n == 0 then return 1
               else return n*f(n-1) end
             end
    end

fat = Z(F)

assert(fat(0) == 1 and fat(4) == 24 and Z(F)(5)==5*Z(F)(4))

local function g (z)
  local function f (a,b,c,d)
    return function (x,y) return a+b+c+d+a+x+y+z end
  end
  return f(z,z+1,z+2,z+3)
end

f = g(10)
assert(f(9, 16) == 10+11+12+13+10+9+16+10)

Z, F, f = nil
print('+')

-- testing multiple returns

function unlpack (t, i)
  i = i or 1
  if (i <= #t) then
    return t[i], unlpack(t, i+1)
  end
end

function equaltab (t1, t2)
  assert(#t1 == #t2)
  for i = 1, #t1 do
    assert(t1[i] == t2[i])
  end
end

local pack = function (...) return (table.pack(...)) end

function f() return 1,2,30,4 end
function ret2 (a,b) return a,b end

local a,b,c,d = unlpack{1,2,3}
assert(a==1 and b==2 and c==3 and d==nil)
a = {1,2,3,4,false,10,'alo',false,assert}
equaltab(pack(unlpack(a)), a)
equaltab(pack(unlpack(a), -1), {1,-1})
a,b,c,d = ret2(f()), ret2(f())
assert(a==1 and b==1 and c==2 and d==nil)
a,b,c,d = unlpack(pack(ret2(f()), ret2(f())))
assert(a==1 and b==1 and c==2 and d==nil)
a,b,c,d = unlpack(pack(ret2(f()), (ret2(f()))))
assert(a==1 and b==1 and c==nil and d==nil)

a = ret2{ unlpack{1,2,3}, unlpack{3,2,1}, unlpack{"a", "b"}}
assert(a[1] == 1 and a[2] == 3 and a[3] == "a" and a[4] == "b")


-- testing calls with 'incorrect' arguments
rawget({}, "x", 1)
rawset({}, "x", 1, 2)
assert(math.sin(1,2) == math.sin(1))
table.sort({10,9,8,4,19,23,0,0}, function (a,b) return a<b end, "extra arg")


-- test for generic load
local x = "-- a comment\0\0\0\n  x = 10 + \n23; \
     local a = function () x = 'hi' end; \
     return '\0'"
function read1 (x)
  local i = 0
  return function ()
    collectgarbage()
    i=i+1
    return string.sub(x, i, i)
  end
end

function cannotload (msg, a,b)
  assert(not a and string.find(b, msg))
end

a = assert(load(read1(x), "modname", "t", _G))
assert(a() == "\0" and _G.x == 33)
assert(debug.getinfo(a).source == "modname")
-- cannot read text in binary mode
cannotload("attempt to load a text chunk", load(read1(x), "modname", "b", {}))
cannotload("attempt to load a text chunk", load(x, "modname", "b"))

a = assert(load(function () return nil end))
a()  -- empty chunk

assert(not load(function () return true end))


-- small bug
local t = {nil, "return ", "3"}
f, msg = load(function () return table.remove(t, 1) end)
assert(f() == nil)   -- should read the empty chunk

x = string.dump(load("x = 1; return x"))
a = assert(load(read1(x), nil, "b"))
assert(a() == 1 and _G.x == 1)
cannotload("attempt to load a binary chunk", load(read1(x), nil, "t"))
cannotload("attempt to load a binary chunk", load(x, nil, "t"))

assert(not pcall(string.dump, print))  -- no dump of C functions

cannotload("unexpected symbol", load(read1("*a = 123")))
cannotload("unexpected symbol", load("*a = 123"))
cannotload("hhi", load(function () error("hhi") end))

-- any value is valid for _ENV
assert(load("return _ENV", nil, nil, 123)() == 123)


-- load when _ENV is not first upvalue
local x; XX = 123
local function h ()
  local y=x   -- use 'x', so that it becomes 1st upvalue
  return XX   -- global name
end
local d = string.dump(h)
x = load(d, "", "b")
assert(debug.getupvalue(x, 2) == '_ENV')
debug.setupvalue(x, 2, _G)
assert(x() == 123)

assert(assert(load("return XX + ...", nil, nil, {XX = 13}))(4) == 17)


-- test generic load with nested functions
x = [[
  return function (x)
    return function (y)
     return function (z)
       return x+y+z
     end
   end
  end
]]

a = assert(load(read1(x)))
assert(a()(2)(3)(10) == 15)


-- test for dump/undump with upvalues
local a, b = 20, 30
x = load(string.dump(function (x)
  if x == "set" then a = 10+b; b = b+1 else
  return a
  end
end))
assert(x() == nil)
assert(debug.setupvalue(x, 1, "hi") == "a")
assert(x() == "hi")
assert(debug.setupvalue(x, 2, 13) == "b")
assert(not debug.setupvalue(x, 3, 10))   -- only 2 upvalues
x("set")
assert(x() == 23)
x("set")
assert(x() == 24)


-- test for bug in parameter adjustment
assert((function () return nil end)(4) == nil)
assert((function () local a; return a end)(4) == nil)
assert((function (a) return a end)() == nil)

print('OK')
return deep
