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|
-- $Id: testes/locals.lua $
-- See Copyright Notice in file all.lua
print('testing local variables and environments')
local debug = require"debug"
local tracegc = require"tracegc"
-- bug in 5.1:
local function f(x) x = nil; return x end
assert(f(10) == nil)
local function f() local x; return x end
assert(f(10) == nil)
local function f(x) x = nil; local y; return x, y end
assert(f(10) == nil and select(2, f(20)) == nil)
do
local i = 10
do local i = 100; assert(i==100) end
do local i = 1000; assert(i==1000) end
assert(i == 10)
if i ~= 10 then
local i = 20
else
local i = 30
assert(i == 30)
end
end
f = nil
local f
local x = 1
a = nil
load('local a = {}')()
assert(a == nil)
function f (a)
local _1, _2, _3, _4, _5
local _6, _7, _8, _9, _10
local x = 3
local b = a
local c,d = a,b
if (d == b) then
local x = 'q'
x = b
assert(x == 2)
else
assert(nil)
end
assert(x == 3)
local f = 10
end
local b=10
local a; repeat local b; a,b=1,2; assert(a+1==b); until a+b==3
assert(x == 1)
f(2)
assert(type(f) == 'function')
local function getenv (f)
local a,b = debug.getupvalue(f, 1)
assert(a == '_ENV')
return b
end
-- test for global table of loaded chunks
assert(getenv(load"a=3") == _G)
local c = {}; local f = load("a = 3", nil, nil, c)
assert(getenv(f) == c)
assert(c.a == nil)
f()
assert(c.a == 3)
-- old test for limits for special instructions
do
local i = 2
local p = 4 -- p == 2^i
repeat
for j=-3,3 do
assert(load(string.format([[local a=%s;
a=a+%s;
assert(a ==2^%s)]], j, p-j, i), '')) ()
assert(load(string.format([[local a=%s;
a=a-%s;
assert(a==-2^%s)]], -j, p-j, i), '')) ()
assert(load(string.format([[local a,b=0,%s;
a=b-%s;
assert(a==-2^%s)]], -j, p-j, i), '')) ()
end
p = 2 * p; i = i + 1
until p <= 0
end
print'+'
if rawget(_G, "T") then
-- testing clearing of dead elements from tables
collectgarbage("stop") -- stop GC
local a = {[{}] = 4, [3] = 0, alo = 1,
a1234567890123456789012345678901234567890 = 10}
local t = T.querytab(a)
for k,_ in pairs(a) do a[k] = undef end
collectgarbage() -- restore GC and collect dead fields in 'a'
for i=0,t-1 do
local k = querytab(a, i)
assert(k == nil or type(k) == 'number' or k == 'alo')
end
-- testing allocation errors during table insertions
local a = {}
local function additems ()
a.x = true; a.y = true; a.z = true
a[1] = true
a[2] = true
end
for i = 1, math.huge do
T.alloccount(i)
local st, msg = pcall(additems)
T.alloccount()
local count = 0
for k, v in pairs(a) do
assert(a[k] == v)
count = count + 1
end
if st then assert(count == 5); break end
end
end
-- testing lexical environments
assert(_ENV == _G)
do
local dummy
local _ENV = (function (...) return ... end)(_G, dummy) -- {
do local _ENV = {assert=assert}; assert(true) end
local mt = {_G = _G}
local foo,x
A = false -- "declare" A
do local _ENV = mt
function foo (x)
A = x
do local _ENV = _G; A = 1000 end
return function (x) return A .. x end
end
end
assert(getenv(foo) == mt)
x = foo('hi'); assert(mt.A == 'hi' and A == 1000)
assert(x('*') == mt.A .. '*')
do local _ENV = {assert=assert, A=10};
do local _ENV = {assert=assert, A=20};
assert(A==20);x=A
end
assert(A==10 and x==20)
end
assert(x==20)
A = nil
do -- constants
local a<const>, b, c<const> = 10, 20, 30
b = a + c + b -- 'b' is not constant
assert(a == 10 and b == 60 and c == 30)
local function checkro (name, code)
local st, msg = load(code)
local gab = string.format("attempt to assign to const variable '%s'", name)
assert(not st and string.find(msg, gab))
end
checkro("y", "local x, y <const>, z = 10, 20, 30; x = 11; y = 12")
checkro("x", "local x <const>, y, z <const> = 10, 20, 30; x = 11")
checkro("z", "local x <const>, y, z <const> = 10, 20, 30; y = 10; z = 11")
checkro("foo", "local foo <const> = 10; function foo() end")
checkro("foo", "local foo <const> = {}; function foo() end")
checkro("z", [[
local a, z <const>, b = 10;
function foo() a = 20; z = 32; end
]])
checkro("var1", [[
local a, var1 <const> = 10;
function foo() a = 20; z = function () var1 = 12; end end
]])
end
print"testing to-be-closed variables"
local function stack(n) n = ((n == 0) or stack(n - 1)) end
local function func2close (f, x, y)
local obj = setmetatable({}, {__close = f})
if x then
return x, obj, y
else
return obj
end
end
do
local a = {}
do
local b <close> = false -- not to be closed
local x <close> = setmetatable({"x"}, {__close = function (self)
a[#a + 1] = self[1] end})
local w, y <close>, z = func2close(function (self, err)
assert(err == nil); a[#a + 1] = "y"
end, 10, 20)
local c <close> = nil -- not to be closed
a[#a + 1] = "in"
assert(w == 10 and z == 20)
end
a[#a + 1] = "out"
assert(a[1] == "in" and a[2] == "y" and a[3] == "x" and a[4] == "out")
end
do
local X = false
local x, closescope = func2close(function (_, msg)
stack(10);
assert(msg == nil)
X = true
end, 100)
assert(x == 100); x = 101; -- 'x' is not read-only
-- closing functions do not corrupt returning values
local function foo (x)
local _ <close> = closescope
return x, X, 23
end
local a, b, c = foo(1.5)
assert(a == 1.5 and b == false and c == 23 and X == true)
X = false
foo = function (x)
local _<close> = func2close(function (_, msg)
-- without errors, enclosing function should be still active when
-- __close is called
assert(debug.getinfo(2).name == "foo")
assert(msg == nil)
end)
local _<close> = closescope
local y = 15
return y
end
assert(foo() == 15 and X == true)
X = false
foo = function ()
local x <close> = closescope
return x
end
assert(foo() == closescope and X == true)
end
do -- testing presence of second argument
local function foo (howtoclose, obj, n)
local ca -- copy of 'a' visible inside its close metamethod
do
local a <close> = func2close(function (...)
local t = table.pack(...)
assert(select("#", ...) == n)
assert(t.n == n and t[1] == ca and (t.n < 2 or t[2] == obj))
ca = 15 -- final value to be returned if howtoclose=="scope"
end)
ca = a
if howtoclose == "ret" then return obj -- 'a' closed by return
elseif howtoclose == "err" then error(obj) -- 'a' closed by error
end
end -- 'a' closed by end of scope
return ca -- ca now should be 15
end
-- with no errors, closing methods receive no extra argument
assert(foo("scope", nil, 1) == 15) -- close by end of scope
assert(foo("ret", 32, 1) == 32) -- close by return
-- with errors, they do
local st, msg = pcall(foo, "err", 23, 2) -- close by error
assert(not st and msg == 23)
end
-- testing to-be-closed x compile-time constants
-- (there were some bugs here in Lua 5.4-rc3, due to a confusion
-- between compile levels and stack levels of variables)
do
local flag = false
local x = setmetatable({},
{__close = function() assert(flag == false); flag = true end})
local y <const> = nil
local z <const> = nil
do
local a <close> = x
end
assert(flag) -- 'x' must be closed here
end
do
-- similar problem, but with implicit close in for loops
local flag = false
local x = setmetatable({},
{__close = function () assert(flag == false); flag = true end})
-- return an empty iterator, nil, nil, and 'x' to be closed
local function a ()
return (function () return nil end), nil, nil, x
end
local v <const> = 1
local w <const> = 1
local x <const> = 1
local y <const> = 1
local z <const> = 1
for k in a() do
a = k
end -- ending the loop must close 'x'
assert(flag) -- 'x' must be closed here
end
do
-- calls cannot be tail in the scope of to-be-closed variables
local X, Y
local function foo ()
local _ <close> = func2close(function () Y = 10 end)
assert(X == true and Y == nil) -- 'X' not closed yet
return 1,2,3
end
local function bar ()
local _ <close> = func2close(function () X = false end)
X = true
do
return foo() -- not a tail call!
end
end
local a, b, c, d = bar()
assert(a == 1 and b == 2 and c == 3 and X == false and Y == 10 and d == nil)
end
do
-- bug in 5.4.3: previous condition (calls cannot be tail in the
-- scope of to-be-closed variables) must be valid for tbc variables
-- created by 'for' loops.
local closed = false
local function foo ()
return function () return true end, 0, 0,
func2close(function () closed = true end)
end
local function tail() return closed end
local function foo1 ()
for k in foo() do return tail() end
end
assert(foo1() == false)
assert(closed == true)
end
do
-- bug in 5.4.4: 'break' may generate wrong 'close' instruction when
-- leaving a loop block.
local closed = false
local o1 = setmetatable({}, {__close=function() closed = true end})
local function test()
for k, v in next, {}, nil, o1 do
local function f() return k end -- create an upvalue
break
end
assert(closed)
end
test()
end
do print("testing errors in __close")
-- original error is in __close
local function foo ()
local x <close> =
func2close(function (self, msg)
assert(string.find(msg, "@y"))
error("@x")
end)
local x1 <close> =
func2close(function (self, msg)
assert(string.find(msg, "@y"))
end)
local gc <close> = func2close(function () collectgarbage() end)
local y <close> =
func2close(function (self, msg)
assert(string.find(msg, "@z")) -- error in 'z'
error("@y")
end)
local z <close> =
func2close(function (self, msg)
assert(msg == nil)
error("@z")
end)
return 200
end
local stat, msg = pcall(foo, false)
assert(string.find(msg, "@x"))
-- original error not in __close
local function foo ()
local x <close> =
func2close(function (self, msg)
-- after error, 'foo' was discarded, so caller now
-- must be 'pcall'
assert(debug.getinfo(2).name == "pcall")
assert(string.find(msg, "@x1"))
end)
local x1 <close> =
func2close(function (self, msg)
assert(debug.getinfo(2).name == "pcall")
assert(string.find(msg, "@y"))
error("@x1")
end)
local gc <close> = func2close(function () collectgarbage() end)
local y <close> =
func2close(function (self, msg)
assert(debug.getinfo(2).name == "pcall")
assert(string.find(msg, "@z"))
error("@y")
end)
local first = true
local z <close> =
func2close(function (self, msg)
assert(debug.getinfo(2).name == "pcall")
-- 'z' close is called once
assert(first and msg == 4)
first = false
error("@z")
end)
error(4) -- original error
end
local stat, msg = pcall(foo, true)
assert(string.find(msg, "@x1"))
-- error leaving a block
local function foo (...)
do
local x1 <close> =
func2close(function (self, msg)
assert(string.find(msg, "@X"))
error("@Y")
end)
local x123 <close> =
func2close(function (_, msg)
assert(msg == nil)
error("@X")
end)
end
os.exit(false) -- should not run
end
local st, msg = xpcall(foo, debug.traceback)
assert(string.match(msg, "^[^ ]* @Y"))
-- error in toclose in vararg function
local function foo (...)
local x123 <close> = func2close(function () error("@x123") end)
end
local st, msg = xpcall(foo, debug.traceback)
assert(string.match(msg, "^[^ ]* @x123"))
assert(string.find(msg, "in metamethod 'close'"))
end
do -- errors due to non-closable values
local function foo ()
local x <close> = {}
os.exit(false) -- should not run
end
local stat, msg = pcall(foo)
assert(not stat and
string.find(msg, "variable 'x' got a non%-closable value"))
local function foo ()
local xyz <close> = setmetatable({}, {__close = print})
getmetatable(xyz).__close = nil -- remove metamethod
end
local stat, msg = pcall(foo)
assert(not stat and string.find(msg, "metamethod 'close'"))
local function foo ()
local a1 <close> = func2close(function (_, msg)
assert(string.find(msg, "number value"))
error(12)
end)
local a2 <close> = setmetatable({}, {__close = print})
local a3 <close> = func2close(function (_, msg)
assert(msg == nil)
error(123)
end)
getmetatable(a2).__close = 4 -- invalidate metamethod
end
local stat, msg = pcall(foo)
assert(not stat and msg == 12)
end
do -- tbc inside close methods
local track = {}
local function foo ()
local x <close> = func2close(function ()
local xx <close> = func2close(function (_, msg)
assert(msg == nil)
track[#track + 1] = "xx"
end)
track[#track + 1] = "x"
end)
track[#track + 1] = "foo"
return 20, 30, 40
end
local a, b, c, d = foo()
assert(a == 20 and b == 30 and c == 40 and d == nil)
assert(track[1] == "foo" and track[2] == "x" and track[3] == "xx")
-- again, with errors
local track = {}
local function foo ()
local x0 <close> = func2close(function (_, msg)
assert(msg == 202)
track[#track + 1] = "x0"
end)
local x <close> = func2close(function ()
local xx <close> = func2close(function (_, msg)
assert(msg == 101)
track[#track + 1] = "xx"
error(202)
end)
track[#track + 1] = "x"
error(101)
end)
track[#track + 1] = "foo"
return 20, 30, 40
end
local st, msg = pcall(foo)
assert(not st and msg == 202)
assert(track[1] == "foo" and track[2] == "x" and track[3] == "xx" and
track[4] == "x0")
end
local function checktable (t1, t2)
assert(#t1 == #t2)
for i = 1, #t1 do
assert(t1[i] == t2[i])
end
end
do -- test for tbc variable high in the stack
-- function to force a stack overflow
local function overflow (n)
overflow(n + 1)
end
-- error handler will create tbc variable handling a stack overflow,
-- high in the stack
local function errorh (m)
assert(string.find(m, "stack overflow"))
local x <close> = func2close(function (o) o[1] = 10 end)
return x
end
local flag
local st, obj
-- run test in a coroutine so as not to swell the main stack
local co = coroutine.wrap(function ()
-- tbc variable down the stack
local y <close> = func2close(function (obj, msg)
assert(msg == nil)
obj[1] = 100
flag = obj
end)
tracegc.stop()
st, obj = xpcall(overflow, errorh, 0)
tracegc.start()
end)
co()
assert(not st and obj[1] == 10 and flag[1] == 100)
end
if rawget(_G, "T") then
do
-- bug in 5.4.3
-- 'lua_settop' may use a pointer to stack invalidated by 'luaF_close'
-- reduce stack size
collectgarbage(); collectgarbage(); collectgarbage()
-- force a stack reallocation
local function loop (n)
if n < 400 then loop(n + 1) end
end
-- close metamethod will reallocate the stack
local o = setmetatable({}, {__close = function () loop(0) end})
local script = [[toclose 2; settop 1; return 1]]
assert(T.testC(script, o) == script)
end
-- memory error inside closing function
local function foo ()
local y <close> = func2close(function () T.alloccount() end)
local x <close> = setmetatable({}, {__close = function ()
T.alloccount(0); local x = {} -- force a memory error
end})
error(1000) -- common error inside the function's body
end
stack(5) -- ensure a minimal number of CI structures
-- despite memory error, 'y' will be executed and
-- memory limit will be lifted
local _, msg = pcall(foo)
assert(msg == "not enough memory")
local closemsg
local close = func2close(function (self, msg)
T.alloccount()
closemsg = msg
end)
-- set a memory limit and return a closing object to remove the limit
local function enter (count)
stack(10) -- reserve some stack space
T.alloccount(count)
closemsg = nil
return close
end
local function test ()
local x <close> = enter(0) -- set a memory limit
local y = {} -- raise a memory error
end
local _, msg = pcall(test)
assert(msg == "not enough memory" and closemsg == "not enough memory")
-- repeat test with extra closing upvalues
local function test ()
local xxx <close> = func2close(function (self, msg)
assert(msg == "not enough memory");
error(1000) -- raise another error
end)
local xx <close> = func2close(function (self, msg)
assert(msg == "not enough memory");
end)
local x <close> = enter(0) -- set a memory limit
local y = {} -- raise a memory error
end
local _, msg = pcall(test)
assert(msg == 1000 and closemsg == "not enough memory")
do -- testing 'toclose' in C string buffer
collectgarbage()
local s = string.rep('a', 10000) -- large string
local m = T.totalmem()
collectgarbage("stop")
s = string.upper(s) -- allocate buffer + new string (10K each)
-- ensure buffer was deallocated
assert(T.totalmem() - m <= 11000)
collectgarbage("restart")
end
do -- now some tests for freeing buffer in case of errors
local lim = 10000 -- some size larger than the static buffer
local extra = 2000 -- some extra memory (for callinfo, etc.)
local s = string.rep("a", lim)
-- concat this table needs two buffer resizes (one for each 's')
local a = {s, s}
collectgarbage(); collectgarbage()
local m = T.totalmem()
collectgarbage("stop")
-- error in the first buffer allocation
T. totalmem(m + extra)
assert(not pcall(table.concat, a))
-- first buffer was not even allocated
assert(T.totalmem() - m <= extra)
-- error in the second buffer allocation
T. totalmem(m + lim + extra)
assert(not pcall(table.concat, a))
-- first buffer was released by 'toclose'
assert(T.totalmem() - m <= extra)
-- userdata, buffer, final string
T.totalmem(m + 2*lim + extra)
assert(#table.concat(a) == 2*lim)
T.totalmem(0) -- remove memory limit
collectgarbage("restart")
print'+'
end
do
-- '__close' vs. return hooks in C functions
local trace = {}
local function hook (event)
trace[#trace + 1] = event .. " " .. (debug.getinfo(2).name or "?")
end
-- create tbc variables to be used by C function
local x = func2close(function (_,msg)
trace[#trace + 1] = "x"
end)
local y = func2close(function (_,msg)
trace[#trace + 1] = "y"
end)
debug.sethook(hook, "r")
local t = {T.testC([[
toclose 2 # x
pushnum 10
pushint 20
toclose 3 # y
return 2
]], x, y)}
debug.sethook()
-- hooks ran before return hook from 'testC'
checktable(trace,
{"return sethook", "y", "return ?", "x", "return ?", "return testC"})
-- results are correct
checktable(t, {10, 20})
end
end
do -- '__close' vs. return hooks in Lua functions
local trace = {}
local function hook (event)
trace[#trace + 1] = event .. " " .. debug.getinfo(2).name
end
local function foo (...)
local x <close> = func2close(function (_,msg)
trace[#trace + 1] = "x"
end)
local y <close> = func2close(function (_,msg)
debug.sethook(hook, "r")
end)
return ...
end
local t = {foo(10,20,30)}
debug.sethook()
checktable(t, {10, 20, 30})
checktable(trace,
{"return sethook", "return close", "x", "return close", "return foo"})
end
print "to-be-closed variables in coroutines"
do
-- yielding inside closing metamethods
local trace = {}
local co = coroutine.wrap(function ()
trace[#trace + 1] = "nowX"
-- will be closed after 'y'
local x <close> = func2close(function (_, msg)
assert(msg == nil)
trace[#trace + 1] = "x1"
coroutine.yield("x")
trace[#trace + 1] = "x2"
end)
return pcall(function ()
do -- 'z' will be closed first
local z <close> = func2close(function (_, msg)
assert(msg == nil)
trace[#trace + 1] = "z1"
coroutine.yield("z")
trace[#trace + 1] = "z2"
end)
end
trace[#trace + 1] = "nowY"
-- will be closed after 'z'
local y <close> = func2close(function(_, msg)
assert(msg == nil)
trace[#trace + 1] = "y1"
coroutine.yield("y")
trace[#trace + 1] = "y2"
end)
return 10, 20, 30
end)
end)
assert(co() == "z")
assert(co() == "y")
assert(co() == "x")
checktable({co()}, {true, 10, 20, 30})
checktable(trace, {"nowX", "z1", "z2", "nowY", "y1", "y2", "x1", "x2"})
end
do
-- yielding inside closing metamethods while returning
-- (bug in 5.4.3)
local extrares -- result from extra yield (if any)
local function check (body, extra, ...)
local t = table.pack(...) -- expected returns
local co = coroutine.wrap(body)
if extra then
extrares = co() -- runs until first (extra) yield
end
local res = table.pack(co()) -- runs until "regular" yield
-- regular yield will yield all values passed to the close function;
-- without errors, that is only the object being closed.
assert(res.n == 1 and type(res[1]) == "table")
local res2 = table.pack(co()) -- runs until end of function
assert(res2.n == t.n)
for i = 1, #t do
if t[i] == "x" then
assert(res2[i] == res[1]) -- value that was closed
else
assert(res2[i] == t[i])
end
end
end
local function foo ()
local x <close> = func2close(coroutine.yield) -- "regular" yield
local extra <close> = func2close(function (self)
assert(self == extrares)
coroutine.yield(100) -- first (extra) yield
end)
extrares = extra
return table.unpack{10, x, 30}
end
check(foo, true, 10, "x", 30)
assert(extrares == 100)
local function foo ()
local x <close> = func2close(coroutine.yield) -- "regular" yield
return
end
check(foo, false)
local function foo ()
local x <close> = func2close(coroutine.yield) -- "regular" yield
local y, z = 20, 30
return x
end
check(foo, false, "x")
local function foo ()
local x <close> = func2close(coroutine.yield) -- "regular" yield
local extra <close> = func2close(coroutine.yield) -- extra yield
return table.unpack({}, 1, 100) -- 100 nils
end
check(foo, true, table.unpack({}, 1, 100))
end
do
-- yielding inside closing metamethods after an error
local co = coroutine.wrap(function ()
local function foo (err)
local z <close> = func2close(function(_, msg)
assert(msg == nil or msg == err + 20)
coroutine.yield("z")
return 100, 200
end)
local y <close> = func2close(function(_, msg)
-- still gets the original error (if any)
assert(msg == err or (msg == nil and err == 1))
coroutine.yield("y")
if err then error(err + 20) end -- creates or changes the error
end)
local x <close> = func2close(function(_, msg)
assert(msg == err or (msg == nil and err == 1))
coroutine.yield("x")
return 100, 200
end)
if err == 10 then error(err) else return 10, 20 end
end
coroutine.yield(pcall(foo, nil)) -- no error
coroutine.yield(pcall(foo, 1)) -- error in __close
return pcall(foo, 10) -- 'foo' will raise an error
end)
local a, b = co() -- first foo: no error
assert(a == "x" and b == nil) -- yields inside 'x'; Ok
a, b = co()
assert(a == "y" and b == nil) -- yields inside 'y'; Ok
a, b = co()
assert(a == "z" and b == nil) -- yields inside 'z'; Ok
local a, b, c = co()
assert(a and b == 10 and c == 20) -- returns from 'pcall(foo, nil)'
local a, b = co() -- second foo: error in __close
assert(a == "x" and b == nil) -- yields inside 'x'; Ok
a, b = co()
assert(a == "y" and b == nil) -- yields inside 'y'; Ok
a, b = co()
assert(a == "z" and b == nil) -- yields inside 'z'; Ok
local st, msg = co() -- reports the error in 'y'
assert(not st and msg == 21)
local a, b = co() -- third foo: error in function body
assert(a == "x" and b == nil) -- yields inside 'x'; Ok
a, b = co()
assert(a == "y" and b == nil) -- yields inside 'y'; Ok
a, b = co()
assert(a == "z" and b == nil) -- yields inside 'z'; Ok
local st, msg = co() -- gets final error
assert(not st and msg == 10 + 20)
end
do
-- an error in a wrapped coroutine closes variables
local x = false
local y = false
local co = coroutine.wrap(function ()
local xv <close> = func2close(function () x = true end)
do
local yv <close> = func2close(function () y = true end)
coroutine.yield(100) -- yield doesn't close variable
end
coroutine.yield(200) -- yield doesn't close variable
error(23) -- error does
end)
local b = co()
assert(b == 100 and not x and not y)
b = co()
assert(b == 200 and not x and y)
local a, b = pcall(co)
assert(not a and b == 23 and x and y)
end
do
-- error in a wrapped coroutine raising errors when closing a variable
local x = 0
local co = coroutine.wrap(function ()
local xx <close> = func2close(function (_, msg)
x = x + 1;
assert(string.find(msg, "@XXX"))
error("@YYY")
end)
local xv <close> = func2close(function () x = x + 1; error("@XXX") end)
coroutine.yield(100)
error(200)
end)
assert(co() == 100); assert(x == 0)
local st, msg = pcall(co); assert(x == 2)
assert(not st and string.find(msg, "@YYY")) -- should get error raised
local x = 0
local y = 0
co = coroutine.wrap(function ()
local xx <close> = func2close(function (_, err)
y = y + 1;
assert(string.find(err, "XXX"))
error("YYY")
end)
local xv <close> = func2close(function ()
x = x + 1; error("XXX")
end)
coroutine.yield(100)
return 200
end)
assert(co() == 100); assert(x == 0)
local st, msg = pcall(co)
assert(x == 1 and y == 1)
-- should get first error raised
assert(not st and string.find(msg, "%w+%.%w+:%d+: YYY"))
end
-- a suspended coroutine should not close its variables when collected
local co
co = coroutine.wrap(function()
-- should not run
local x <close> = func2close(function () os.exit(false) end)
co = nil
coroutine.yield()
end)
co() -- start coroutine
assert(co == nil) -- eventually it will be collected
collectgarbage()
if rawget(_G, "T") then
print("to-be-closed variables x coroutines in C")
do
local token = 0
local count = 0
local f = T.makeCfunc[[
toclose 1
toclose 2
return .
]]
local obj = func2close(function (_, msg)
count = count + 1
token = coroutine.yield(count, token)
end)
local co = coroutine.wrap(f)
local ct, res = co(obj, obj, 10, 20, 30, 3) -- will return 10, 20, 30
-- initial token value, after closing 2nd obj
assert(ct == 1 and res == 0)
-- run until yield when closing 1st obj
ct, res = co(100)
assert(ct == 2 and res == 100)
res = {co(200)} -- run until end
assert(res[1] == 10 and res[2] == 20 and res[3] == 30 and res[4] == nil)
assert(token == 200)
end
do
local f = T.makeCfunc[[
toclose 1
return .
]]
local obj = func2close(function ()
local temp
local x <close> = func2close(function ()
coroutine.yield(temp)
return 1,2,3 -- to be ignored
end)
temp = coroutine.yield("closing obj")
return 1,2,3 -- to be ignored
end)
local co = coroutine.wrap(f)
local res = co(obj, 10, 30, 1) -- will return only 30
assert(res == "closing obj")
res = co("closing x")
assert(res == "closing x")
res = {co()}
assert(res[1] == 30 and res[2] == nil)
end
do
-- still cannot yield inside 'closeslot'
local f = T.makeCfunc[[
toclose 1
closeslot 1
]]
local obj = func2close(coroutine.yield)
local co = coroutine.create(f)
local st, msg = coroutine.resume(co, obj)
assert(not st and string.find(msg, "attempt to yield across"))
-- nor outside a coroutine
local f = T.makeCfunc[[
toclose 1
]]
local st, msg = pcall(f, obj)
assert(not st and string.find(msg, "attempt to yield from outside"))
end
end
-- to-be-closed variables in generic for loops
do
local numopen = 0
local function open (x)
numopen = numopen + 1
return
function () -- iteraction function
x = x - 1
if x > 0 then return x end
end,
nil, -- state
nil, -- control variable
func2close(function () numopen = numopen - 1 end) -- closing function
end
local s = 0
for i in open(10) do
s = s + i
end
assert(s == 45 and numopen == 0)
local s = 0
for i in open(10) do
if i < 5 then break end
s = s + i
end
assert(s == 35 and numopen == 0)
local s = 0
for i in open(10) do
for j in open(10) do
if i + j < 5 then goto endloop end
s = s + i
end
end
::endloop::
assert(s == 375 and numopen == 0)
end
print('OK')
return 5,f
end -- }
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