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|
-- $Id: testes/nextvar.lua $
-- See Copyright Notice in file all.lua
print('testing tables, next, and for')
local function checkerror (msg, f, ...)
local s, err = pcall(f, ...)
assert(not s and string.find(err, msg))
end
local a = {}
-- make sure table has lots of space in hash part
for i=1,100 do a[i.."+"] = true end
for i=1,100 do a[i.."+"] = undef end
-- fill hash part with numeric indices testing size operator
for i=1,100 do
a[i] = true
assert(#a == i)
end
-- testing ipairs
local x = 0
for k,v in ipairs{10,20,30;x=12} do
x = x + 1
assert(k == x and v == x * 10)
end
for _ in ipairs{x=12, y=24} do assert(nil) end
-- test for 'false' x ipair
x = false
local i = 0
for k,v in ipairs{true,false,true,false} do
i = i + 1
x = not x
assert(x == v)
end
assert(i == 4)
-- iterator function is always the same
assert(type(ipairs{}) == 'function' and ipairs{} == ipairs{})
do -- overflow (must wrap-around)
local f = ipairs{}
local k, v = f({[math.mininteger] = 10}, math.maxinteger)
assert(k == math.mininteger and v == 10)
k, v = f({[math.mininteger] = 10}, k)
assert(k == nil)
end
if not T then
(Message or print)
('\n >>> testC not active: skipping tests for table sizes <<<\n')
else --[
-- testing table sizes
local function mp2 (n) -- minimum power of 2 >= n
local mp = 2^math.ceil(math.log(n, 2))
assert(n == 0 or (mp/2 < n and n <= mp))
return mp
end
local function check (t, na, nh)
local a, h = T.querytab(t)
if a ~= na or h ~= nh then
print(na, nh, a, h)
assert(nil)
end
end
-- testing C library sizes
do
local s = 0
for _ in pairs(math) do s = s + 1 end
check(math, 0, mp2(s))
end
-- testing constructor sizes
local sizes = {0, 1, 2, 3, 4, 5, 7, 8, 9, 15, 16, 17,
30, 31, 32, 33, 34, 254, 255, 256, 500, 1000}
for _, sa in ipairs(sizes) do -- 'sa' is size of the array part
local arr = {"return {"}
for i = 1, sa do arr[1 + i] = "1," end -- build array part
for _, sh in ipairs(sizes) do -- 'sh' is size of the hash part
for j = 1, sh do -- build hash part
arr[1 + sa + j] = string.format('k%x=%d,', j, j)
end
arr[1 + sa + sh + 1] = "}"
local prog = table.concat(arr)
local f = assert(load(prog))
collectgarbage("stop")
f() -- call once to ensure stack space
-- make sure table is not resized after being created
if sa == 0 or sh == 0 then
T.alloccount(2); -- header + array or hash part
else
T.alloccount(3); -- header + array part + hash part
end
local t = f()
T.alloccount();
collectgarbage("restart")
assert(#t == sa)
check(t, sa, mp2(sh))
end
end
-- tests with unknown number of elements
local a = {}
for i=1,sizes[#sizes] do a[i] = i end -- build auxiliary table
for k in ipairs(sizes) do
local t = {table.unpack(a,1,k)}
assert(#t == k)
check(t, k, 0)
t = {1,2,3,table.unpack(a,1,k)}
check(t, k+3, 0)
assert(#t == k + 3)
end
-- testing tables dynamically built
local lim = 130
local a = {}; a[2] = 1; check(a, 0, 1)
a = {}; a[0] = 1; check(a, 0, 1); a[2] = 1; check(a, 0, 2)
a = {}; a[0] = 1; a[1] = 1; check(a, 1, 1)
a = {}
for i = 1,lim do
a[i] = 1
assert(#a == i)
check(a, mp2(i), 0)
end
a = {}
for i = 1,lim do
a['a'..i] = 1
assert(#a == 0)
check(a, 0, mp2(i))
end
a = {}
for i=1,16 do a[i] = i end
check(a, 16, 0)
do
for i=1,11 do a[i] = undef end
for i=30,50 do a[i] = true; a[i] = undef end -- force a rehash (?)
check(a, 0, 8) -- 5 elements in the table
a[10] = 1
for i=30,50 do a[i] = true; a[i] = undef end -- force a rehash (?)
check(a, 0, 8) -- only 6 elements in the table
for i=1,14 do a[i] = true; a[i] = undef end
for i=18,50 do a[i] = true; a[i] = undef end -- force a rehash (?)
check(a, 0, 4) -- only 2 elements ([15] and [16])
end
-- reverse filling
for i=1,lim do
local a = {}
for i=i,1,-1 do a[i] = i end -- fill in reverse
check(a, mp2(i), 0)
end
-- size tests for vararg
lim = 35
function foo (n, ...)
local arg = {...}
check(arg, n, 0)
assert(select('#', ...) == n)
arg[n+1] = true
check(arg, mp2(n+1), 0)
arg.x = true
check(arg, mp2(n+1), 1)
end
local a = {}
for i=1,lim do a[i] = true; foo(i, table.unpack(a)) end
-- Table length with limit smaller than maximum value at array
local a = {}
for i = 1,64 do a[i] = true end -- make its array size 64
for i = 1,64 do a[i] = nil end -- erase all elements
assert(T.querytab(a) == 64) -- array part has 64 elements
a[32] = true; a[48] = true; -- binary search will find these ones
a[51] = true -- binary search will miss this one
assert(#a == 48) -- this will set the limit
assert(select(4, T.querytab(a)) == 48) -- this is the limit now
a[50] = true -- this will set a new limit
assert(select(4, T.querytab(a)) == 50) -- this is the limit now
-- but the size is larger (and still inside the array part)
assert(#a == 51)
end --]
-- test size operation on tables with nils
assert(#{} == 0)
assert(#{nil} == 0)
assert(#{nil, nil} == 0)
assert(#{nil, nil, nil} == 0)
assert(#{nil, nil, nil, nil} == 0)
assert(#{1, 2, 3, nil, nil} == 3)
print'+'
local nofind = {}
a,b,c = 1,2,3
a,b,c = nil
-- next uses always the same iteraction function
assert(next{} == next{})
local function find (name)
local n,v
while 1 do
n,v = next(_G, n)
if not n then return nofind end
assert(_G[n] ~= undef)
if n == name then return v end
end
end
local function find1 (name)
for n,v in pairs(_G) do
if n==name then return v end
end
return nil -- not found
end
assert(print==find("print") and print == find1("print"))
assert(_G["print"]==find("print"))
assert(assert==find1("assert"))
assert(nofind==find("return"))
assert(not find1("return"))
_G["ret" .. "urn"] = undef
assert(nofind==find("return"))
_G["xxx"] = 1
assert(xxx==find("xxx"))
-- invalid key to 'next'
checkerror("invalid key", next, {10,20}, 3)
-- both 'pairs' and 'ipairs' need an argument
checkerror("bad argument", pairs)
checkerror("bad argument", ipairs)
print('+')
a = {}
for i=0,10000 do
if math.fmod(i,10) ~= 0 then
a['x'..i] = i
end
end
n = {n=0}
for i,v in pairs(a) do
n.n = n.n+1
assert(i and v and a[i] == v)
end
assert(n.n == 9000)
a = nil
do -- clear global table
local a = {}
for n,v in pairs(_G) do a[n]=v end
for n,v in pairs(a) do
if not package.loaded[n] and type(v) ~= "function" and
not string.find(n, "^[%u_]") then
_G[n] = undef
end
collectgarbage()
end
end
--
local function checknext (a)
local b = {}
do local k,v = next(a); while k do b[k] = v; k,v = next(a,k) end end
for k,v in pairs(b) do assert(a[k] == v) end
for k,v in pairs(a) do assert(b[k] == v) end
end
checknext{1,x=1,y=2,z=3}
checknext{1,2,x=1,y=2,z=3}
checknext{1,2,3,x=1,y=2,z=3}
checknext{1,2,3,4,x=1,y=2,z=3}
checknext{1,2,3,4,5,x=1,y=2,z=3}
assert(#{} == 0)
assert(#{[-1] = 2} == 0)
for i=0,40 do
local a = {}
for j=1,i do a[j]=j end
assert(#a == i)
end
-- 'maxn' is now deprecated, but it is easily defined in Lua
function table.maxn (t)
local max = 0
for k in pairs(t) do
max = (type(k) == 'number') and math.max(max, k) or max
end
return max
end
assert(table.maxn{} == 0)
assert(table.maxn{["1000"] = true} == 0)
assert(table.maxn{["1000"] = true, [24.5] = 3} == 24.5)
assert(table.maxn{[1000] = true} == 1000)
assert(table.maxn{[10] = true, [100*math.pi] = print} == 100*math.pi)
table.maxn = nil
-- int overflow
a = {}
for i=0,50 do a[2^i] = true end
assert(a[#a])
print('+')
do -- testing 'next' with all kinds of keys
local a = {
[1] = 1, -- integer
[1.1] = 2, -- float
['x'] = 3, -- short string
[string.rep('x', 1000)] = 4, -- long string
[print] = 5, -- C function
[checkerror] = 6, -- Lua function
[coroutine.running()] = 7, -- thread
[true] = 8, -- boolean
[io.stdin] = 9, -- userdata
[{}] = 10, -- table
}
local b = {}; for i = 1, 10 do b[i] = true end
for k, v in pairs(a) do
assert(b[v]); b[v] = undef
end
assert(next(b) == nil) -- 'b' now is empty
end
-- erasing values
local t = {[{1}] = 1, [{2}] = 2, [string.rep("x ", 4)] = 3,
[100.3] = 4, [4] = 5}
local n = 0
for k, v in pairs( t ) do
n = n+1
assert(t[k] == v)
t[k] = undef
collectgarbage()
assert(t[k] == undef)
end
assert(n == 5)
do
print("testing next x GC of deleted keys")
-- bug in 5.4.1
local co = coroutine.wrap(function (t)
for k, v in pairs(t) do
local k1 = next(t) -- all previous keys were deleted
assert(k == k1) -- current key is the first in the table
t[k] = nil
local expected = (type(k) == "table" and k[1] or
type(k) == "function" and k() or
string.sub(k, 1, 1))
assert(expected == v)
coroutine.yield(v)
end
end)
local t = {}
t[{1}] = 1 -- add several unanchored, collectable keys
t[{2}] = 2
t[string.rep("a", 50)] = "a" -- long string
t[string.rep("b", 50)] = "b"
t[{3}] = 3
t[string.rep("c", 10)] = "c" -- short string
t[function () return 10 end] = 10
local count = 7
while co(t) do
collectgarbage("collect") -- collect dead keys
count = count - 1
end
assert(count == 0 and next(t) == nil) -- traversed the whole table
end
local function test (a)
assert(not pcall(table.insert, a, 2, 20));
table.insert(a, 10); table.insert(a, 2, 20);
table.insert(a, 1, -1); table.insert(a, 40);
table.insert(a, #a+1, 50)
table.insert(a, 2, -2)
assert(a[2] ~= undef)
assert(a["2"] == undef)
assert(not pcall(table.insert, a, 0, 20));
assert(not pcall(table.insert, a, #a + 2, 20));
assert(table.remove(a,1) == -1)
assert(table.remove(a,1) == -2)
assert(table.remove(a,1) == 10)
assert(table.remove(a,1) == 20)
assert(table.remove(a,1) == 40)
assert(table.remove(a,1) == 50)
assert(table.remove(a,1) == nil)
assert(table.remove(a) == nil)
assert(table.remove(a, #a) == nil)
end
a = {n=0, [-7] = "ban"}
test(a)
assert(a.n == 0 and a[-7] == "ban")
a = {[-7] = "ban"};
test(a)
assert(a.n == nil and #a == 0 and a[-7] == "ban")
a = {[-1] = "ban"}
test(a)
assert(#a == 0 and table.remove(a) == nil and a[-1] == "ban")
a = {[0] = "ban"}
assert(#a == 0 and table.remove(a) == "ban" and a[0] == undef)
table.insert(a, 1, 10); table.insert(a, 1, 20); table.insert(a, 1, -1)
assert(table.remove(a) == 10)
assert(table.remove(a) == 20)
assert(table.remove(a) == -1)
assert(table.remove(a) == nil)
a = {'c', 'd'}
table.insert(a, 3, 'a')
table.insert(a, 'b')
assert(table.remove(a, 1) == 'c')
assert(table.remove(a, 1) == 'd')
assert(table.remove(a, 1) == 'a')
assert(table.remove(a, 1) == 'b')
assert(table.remove(a, 1) == nil)
assert(#a == 0 and a.n == nil)
a = {10,20,30,40}
assert(table.remove(a, #a + 1) == nil)
assert(not pcall(table.remove, a, 0))
assert(a[#a] == 40)
assert(table.remove(a, #a) == 40)
assert(a[#a] == 30)
assert(table.remove(a, 2) == 20)
assert(a[#a] == 30 and #a == 2)
do -- testing table library with metamethods
local function test (proxy, t)
for i = 1, 10 do
table.insert(proxy, 1, i)
end
assert(#proxy == 10 and #t == 10 and proxy[1] ~= undef)
for i = 1, 10 do
assert(t[i] == 11 - i)
end
table.sort(proxy)
for i = 1, 10 do
assert(t[i] == i and proxy[i] == i)
end
assert(table.concat(proxy, ",") == "1,2,3,4,5,6,7,8,9,10")
for i = 1, 8 do
assert(table.remove(proxy, 1) == i)
end
assert(#proxy == 2 and #t == 2)
local a, b, c = table.unpack(proxy)
assert(a == 9 and b == 10 and c == nil)
end
-- all virtual
local t = {}
local proxy = setmetatable({}, {
__len = function () return #t end,
__index = t,
__newindex = t,
})
test(proxy, t)
-- only __newindex
local count = 0
t = setmetatable({}, {
__newindex = function (t,k,v) count = count + 1; rawset(t,k,v) end})
test(t, t)
assert(count == 10) -- after first 10, all other sets are not new
-- no __newindex
t = setmetatable({}, {
__index = function (_,k) return k + 1 end,
__len = function (_) return 5 end})
assert(table.concat(t, ";") == "2;3;4;5;6")
end
do -- testing overflow in table.insert (must wrap-around)
local t = setmetatable({},
{__len = function () return math.maxinteger end})
table.insert(t, 20)
local k, v = next(t)
assert(k == math.mininteger and v == 20)
end
if not T then
(Message or print)
('\n >>> testC not active: skipping tests for table library on non-tables <<<\n')
else --[
local debug = require'debug'
local tab = {10, 20, 30}
local mt = {}
local u = T.newuserdata(0)
checkerror("table expected", table.insert, u, 40)
checkerror("table expected", table.remove, u)
debug.setmetatable(u, mt)
checkerror("table expected", table.insert, u, 40)
checkerror("table expected", table.remove, u)
mt.__index = tab
checkerror("table expected", table.insert, u, 40)
checkerror("table expected", table.remove, u)
mt.__newindex = tab
checkerror("table expected", table.insert, u, 40)
checkerror("table expected", table.remove, u)
mt.__len = function () return #tab end
table.insert(u, 40)
assert(#u == 4 and #tab == 4 and u[4] == 40 and tab[4] == 40)
assert(table.remove(u) == 40)
table.insert(u, 1, 50)
assert(#u == 4 and #tab == 4 and u[4] == 30 and tab[1] == 50)
mt.__newindex = nil
mt.__len = nil
local tab2 = {}
local u2 = T.newuserdata(0)
debug.setmetatable(u2, {__newindex = function (_, k, v) tab2[k] = v end})
table.move(u, 1, 4, 1, u2)
assert(#tab2 == 4 and tab2[1] == tab[1] and tab2[4] == tab[4])
end -- ]
print('+')
a = {}
for i=1,1000 do
a[i] = i; a[i - 1] = undef
end
assert(next(a,nil) == 1000 and next(a,1000) == nil)
assert(next({}) == nil)
assert(next({}, nil) == nil)
for a,b in pairs{} do error"not here" end
for i=1,0 do error'not here' end
for i=0,1,-1 do error'not here' end
a = nil; for i=1,1 do assert(not a); a=1 end; assert(a)
a = nil; for i=1,1,-1 do assert(not a); a=1 end; assert(a)
do
print("testing floats in numeric for")
local a
-- integer count
a = 0; for i=1, 1, 1 do a=a+1 end; assert(a==1)
a = 0; for i=10000, 1e4, -1 do a=a+1 end; assert(a==1)
a = 0; for i=1, 0.99999, 1 do a=a+1 end; assert(a==0)
a = 0; for i=9999, 1e4, -1 do a=a+1 end; assert(a==0)
a = 0; for i=1, 0.99999, -1 do a=a+1 end; assert(a==1)
-- float count
a = 0; for i=0, 0.999999999, 0.1 do a=a+1 end; assert(a==10)
a = 0; for i=1.0, 1, 1 do a=a+1 end; assert(a==1)
a = 0; for i=-1.5, -1.5, 1 do a=a+1 end; assert(a==1)
a = 0; for i=1e6, 1e6, -1 do a=a+1 end; assert(a==1)
a = 0; for i=1.0, 0.99999, 1 do a=a+1 end; assert(a==0)
a = 0; for i=99999, 1e5, -1.0 do a=a+1 end; assert(a==0)
a = 0; for i=1.0, 0.99999, -1 do a=a+1 end; assert(a==1)
end
do -- changing the control variable
local a
a = 0; for i = 1, 10 do a = a + 1; i = "x" end; assert(a == 10)
a = 0; for i = 10.0, 1, -1 do a = a + 1; i = "x" end; assert(a == 10)
end
-- conversion
a = 0; for i="10","1","-2" do a=a+1 end; assert(a==5)
do -- checking types
local c
local function checkfloat (i)
assert(math.type(i) == "float")
c = c + 1
end
c = 0; for i = 1.0, 10 do checkfloat(i) end
assert(c == 10)
c = 0; for i = -1, -10, -1.0 do checkfloat(i) end
assert(c == 10)
local function checkint (i)
assert(math.type(i) == "integer")
c = c + 1
end
local m = math.maxinteger
c = 0; for i = m, m - 10, -1 do checkint(i) end
assert(c == 11)
c = 0; for i = 1, 10.9 do checkint(i) end
assert(c == 10)
c = 0; for i = 10, 0.001, -1 do checkint(i) end
assert(c == 10)
c = 0; for i = 1, "10.8" do checkint(i) end
assert(c == 10)
c = 0; for i = 9, "3.4", -1 do checkint(i) end
assert(c == 6)
c = 0; for i = 0, " -3.4 ", -1 do checkint(i) end
assert(c == 4)
c = 0; for i = 100, "96.3", -2 do checkint(i) end
assert(c == 2)
c = 0; for i = 1, math.huge do if i > 10 then break end; checkint(i) end
assert(c == 10)
c = 0; for i = -1, -math.huge, -1 do
if i < -10 then break end; checkint(i)
end
assert(c == 10)
for i = math.mininteger, -10e100 do assert(false) end
for i = math.maxinteger, 10e100, -1 do assert(false) end
end
do -- testing other strange cases for numeric 'for'
local function checkfor (from, to, step, t)
local c = 0
for i = from, to, step do
c = c + 1
assert(i == t[c])
end
assert(c == #t)
end
local maxi = math.maxinteger
local mini = math.mininteger
checkfor(mini, maxi, maxi, {mini, -1, maxi - 1})
checkfor(mini, math.huge, maxi, {mini, -1, maxi - 1})
checkfor(maxi, mini, mini, {maxi, -1})
checkfor(maxi, mini, -maxi, {maxi, 0, -maxi})
checkfor(maxi, -math.huge, mini, {maxi, -1})
checkfor(maxi, mini, 1, {})
checkfor(mini, maxi, -1, {})
checkfor(maxi - 6, maxi, 3, {maxi - 6, maxi - 3, maxi})
checkfor(mini + 4, mini, -2, {mini + 4, mini + 2, mini})
local step = maxi // 10
local c = mini
for i = mini, maxi, step do
assert(i == c)
c = c + step
end
c = maxi
for i = maxi, mini, -step do
assert(i == c)
c = c - step
end
checkfor(maxi, maxi, maxi, {maxi})
checkfor(maxi, maxi, mini, {maxi})
checkfor(mini, mini, maxi, {mini})
checkfor(mini, mini, mini, {mini})
end
checkerror("'for' step is zero", function ()
for i = 1, 10, 0 do end
end)
checkerror("'for' step is zero", function ()
for i = 1, -10, 0 do end
end)
checkerror("'for' step is zero", function ()
for i = 1.0, -10, 0.0 do end
end)
collectgarbage()
-- testing generic 'for'
local function f (n, p)
local t = {}; for i=1,p do t[i] = i*10 end
return function (_, n, ...)
assert(select("#", ...) == 0) -- no extra arguments
if n > 0 then
n = n-1
return n, table.unpack(t)
end
end, nil, n
end
local x = 0
for n,a,b,c,d in f(5,3) do
x = x+1
assert(a == 10 and b == 20 and c == 30 and d == nil)
end
assert(x == 5)
-- testing __pairs and __ipairs metamethod
a = {}
do
local x,y,z = pairs(a)
assert(type(x) == 'function' and y == a and z == nil)
end
local function foo (e,i)
assert(e == a)
if i <= 10 then return i+1, i+2 end
end
local function foo1 (e,i)
i = i + 1
assert(e == a)
if i <= e.n then return i,a[i] end
end
setmetatable(a, {__pairs = function (x) return foo, x, 0 end})
local i = 0
for k,v in pairs(a) do
i = i + 1
assert(k == i and v == k+1)
end
a.n = 5
a[3] = 30
-- testing ipairs with metamethods
a = {n=10}
setmetatable(a, { __index = function (t,k)
if k <= t.n then return k * 10 end
end})
i = 0
for k,v in ipairs(a) do
i = i + 1
assert(k == i and v == i * 10)
end
assert(i == a.n)
-- testing yield inside __pairs
do
local t = setmetatable({10, 20, 30}, {__pairs = function (t)
local inc = coroutine.yield()
return function (t, i)
if i > 1 then return i - inc, t[i - inc] else return nil end
end, t, #t + 1
end})
local res = {}
local co = coroutine.wrap(function ()
for i,p in pairs(t) do res[#res + 1] = p end
end)
co() -- start coroutine
co(1) -- continue after yield
assert(res[1] == 30 and res[2] == 20 and res[3] == 10 and #res == 3)
end
print"OK"
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