Report last error in closing methods

When there are multiple errors around closing methods, report the
last error instead of the original.
This commit is contained in:
Roberto Ierusalimschy 2020-12-22 10:54:25 -03:00
parent f9d29b0c44
commit 0ceada8da9
5 changed files with 35 additions and 101 deletions

View File

@ -75,8 +75,11 @@ static int luaB_auxwrap (lua_State *L) {
int r = auxresume(L, co, lua_gettop(L));
if (r < 0) { /* error? */
int stat = lua_status(co);
if (stat != LUA_OK && stat != LUA_YIELD) /* error in the coroutine? */
lua_resetthread(co); /* close its tbc variables */
if (stat != LUA_OK && stat != LUA_YIELD) { /* error in the coroutine? */
stat = lua_resetthread(co); /* close its tbc variables */
lua_assert(stat != LUA_OK);
lua_xmove(co, L, 1); /* copy error message */
}
if (stat != LUA_ERRMEM && /* not a memory error and ... */
lua_type(L, -1) == LUA_TSTRING) { /* ... error object is a string? */
luaL_where(L, 1); /* add extra info, if available */

10
lfunc.c
View File

@ -162,14 +162,10 @@ static int callclosemth (lua_State *L, StkId level, int status) {
luaD_seterrorobj(L, status, level); /* set error message */
if (prepclosingmethod(L, uv, s2v(level))) { /* something to call? */
int newstatus = luaD_pcall(L, callclose, NULL, oldtop, 0);
if (newstatus != LUA_OK && status == CLOSEPROTECT) /* first error? */
status = newstatus; /* this will be the new error */
else {
if (newstatus != LUA_OK) /* suppressed error? */
luaE_warnerror(L, "__close metamethod");
/* leave original error (or nil) on top */
if (newstatus != LUA_OK) /* new error? */
status = newstatus; /* this will be the error now */
else /* leave original error (or nil) on top */
L->top = restorestack(L, oldtop);
}
}
/* else no metamethod; ignore this case and keep original error */
}

View File

@ -1630,13 +1630,8 @@ they are closed in the reverse order that they were declared.
If there is any error while running a closing method,
that error is handled like an error in the regular code
where the variable was defined.
After an error,
the other pending closing methods will still be called.
Errors in these methods
interrupt the respective method and generate a warning,
but are otherwise ignored;
the error reported is only the original one.
If a coroutine yields and is never resumed again,
some variables may never go out of scope,

View File

@ -172,13 +172,12 @@ do
assert(not X and coroutine.status(co) == "dead")
-- error closing a coroutine
warn("@on")
local x = 0
co = coroutine.create(function()
local y <close> = func2close(function (self,err)
if (err ~= 111) then os.exit(false) end -- should not happen
assert(err == 111)
x = 200
error("200")
error(200)
end)
local x <close> = func2close(function (self, err)
assert(err == nil); error(111)
@ -187,16 +186,8 @@ do
end)
coroutine.resume(co)
assert(x == 0)
-- with test library, use 'store' mode to check warnings
warn(not T and "@off" or "@store")
local st, msg = coroutine.close(co)
if not T then
warn("@on")
else -- test library
assert(string.find(_WARN, "200")); _WARN = false
warn("@normal")
end
assert(st == false and coroutine.status(co) == "dead" and msg == 111)
assert(st == false and coroutine.status(co) == "dead" and msg == 200)
assert(x == 200)
end

View File

@ -232,7 +232,11 @@ end
do
local X = false
local x, closescope = func2close(function () stack(10); X = true end, 100)
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
@ -246,10 +250,11 @@ do
X = false
foo = function (x)
local _<close> = func2close(function ()
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
@ -328,64 +333,20 @@ do
end
-- auxiliary functions for testing warnings in '__close'
local function prepwarn ()
if not T then -- no test library?
warn("@off") -- do not show (lots of) warnings
else
warn("@store") -- to test the warnings
end
end
local function endwarn ()
if not T then
warn("@on") -- back to normal
else
assert(_WARN == false)
warn("@normal")
end
end
-- errors inside __close can generate a warning instead of an
-- error. This new 'assert' force them to appear.
local function assert(cond, msg)
if not cond then
local line = debug.getinfo(2).currentline or "?"
msg = string.format("assertion failed! line %d (%s)\n", line, msg or "")
io.stderr:write(msg)
os.exit(1)
end
end
local function checkwarn (msg)
if T then
assert(_WARN and string.find(_WARN, msg))
_WARN = false -- reset variable to check next warning
end
end
warn("@on")
do print("testing errors in __close")
prepwarn()
-- original error is in __close
local function foo ()
local x <close> =
func2close(function (self, msg)
assert(string.find(msg, "@z"))
assert(string.find(msg, "@y"))
error("@x")
end)
local x1 <close> =
func2close(function (self, msg)
checkwarn("@y")
assert(string.find(msg, "@z"))
assert(string.find(msg, "@y"))
end)
local gc <close> = func2close(function () collectgarbage() end)
@ -406,8 +367,7 @@ do print("testing errors in __close")
end
local stat, msg = pcall(foo, false)
assert(string.find(msg, "@z"))
checkwarn("@x")
assert(string.find(msg, "@x"))
-- original error not in __close
@ -418,14 +378,13 @@ do print("testing errors in __close")
-- after error, 'foo' was discarded, so caller now
-- must be 'pcall'
assert(debug.getinfo(2).name == "pcall")
assert(msg == 4)
assert(string.find(msg, "@x1"))
end)
local x1 <close> =
func2close(function (self, msg)
assert(debug.getinfo(2).name == "pcall")
checkwarn("@y")
assert(msg == 4)
assert(string.find(msg, "@y"))
error("@x1")
end)
@ -434,8 +393,7 @@ do print("testing errors in __close")
local y <close> =
func2close(function (self, msg)
assert(debug.getinfo(2).name == "pcall")
assert(msg == 4) -- error in body
checkwarn("@z")
assert(string.find(msg, "@z"))
error("@y")
end)
@ -453,8 +411,7 @@ do print("testing errors in __close")
end
local stat, msg = pcall(foo, true)
assert(msg == 4)
checkwarn("@x1") -- last error
assert(string.find(msg, "@x1"))
-- error leaving a block
local function foo (...)
@ -466,7 +423,8 @@ do print("testing errors in __close")
end)
local x123 <close> =
func2close(function ()
func2close(function (_, msg)
assert(msg == nil)
error("@X")
end)
end
@ -474,9 +432,7 @@ do print("testing errors in __close")
end
local st, msg = xpcall(foo, debug.traceback)
assert(string.match(msg, "^[^ ]* @X"))
assert(string.find(msg, "in metamethod 'close'"))
checkwarn("@Y")
assert(string.match(msg, "^[^ ]* @Y"))
-- error in toclose in vararg function
local function foo (...)
@ -486,7 +442,6 @@ do print("testing errors in __close")
local st, msg = xpcall(foo, debug.traceback)
assert(string.match(msg, "^[^ ]* @x123"))
assert(string.find(msg, "in metamethod 'close'"))
endwarn()
end
@ -511,8 +466,6 @@ end
if rawget(_G, "T") then
warn("@off")
-- memory error inside closing function
local function foo ()
local y <close> = func2close(function () T.alloccount() end)
@ -527,7 +480,7 @@ if rawget(_G, "T") then
-- despite memory error, 'y' will be executed and
-- memory limit will be lifted
local _, msg = pcall(foo)
assert(msg == 1000)
assert(msg == "not enough memory")
local close = func2close(function (self, msg)
T.alloccount()
@ -570,7 +523,7 @@ if rawget(_G, "T") then
end
local _, msg = pcall(test)
assert(msg == "not enough memory") -- reported error is the first one
assert(msg == 1000)
do -- testing 'toclose' in C string buffer
collectgarbage()
@ -625,7 +578,6 @@ if rawget(_G, "T") then
print'+'
end
warn("@on")
end
@ -655,14 +607,14 @@ end
do
prepwarn()
-- error in a wrapped coroutine raising errors when closing a variable
local x = 0
local co = coroutine.wrap(function ()
local xx <close> = func2close(function ()
local xx <close> = func2close(function (_, msg)
x = x + 1;
checkwarn("@XXX"); error("@YYY")
assert(string.find(msg, "@XXX"))
error("@YYY")
end)
local xv <close> = func2close(function () x = x + 1; error("@XXX") end)
coroutine.yield(100)
@ -670,8 +622,7 @@ do
end)
assert(co() == 100); assert(x == 0)
local st, msg = pcall(co); assert(x == 2)
assert(not st and msg == 200) -- should get first error raised
checkwarn("@YYY")
assert(not st and string.find(msg, "@YYY")) -- should get error raised
local x = 0
local y = 0
@ -691,10 +642,8 @@ do
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+: XXX"))
checkwarn("YYY")
assert(not st and string.find(msg, "%w+%.%w+:%d+: YYY"))
endwarn()
end