From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Serge Petrenko Message-Id: <99BE7A8E-0166-4B42-887D-60B6F8AE005A@tarantool.org> Content-Type: multipart/alternative; boundary="Apple-Mail=_BA428227-4882-4DFD-982A-7B0293E22A48" Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Subject: Re: [tarantool-patches] Re: [PATCH] lua: fix decimal comparison with box.NULL Date: Tue, 27 Aug 2019 15:37:01 +0300 In-Reply-To: <20190827122535.GO13834@esperanza> References: <20190827112209.43581-1-sergepetrenko@tarantool.org> <20190827120448.GN13834@esperanza> <940F74CC-9A3F-49CE-9B1D-A265D27B08A5@tarantool.org> <20190827122535.GO13834@esperanza> To: Vladimir Davydov Cc: tarantool-patches@freelists.org List-ID: --Apple-Mail=_BA428227-4882-4DFD-982A-7B0293E22A48 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 > 27 =D0=B0=D0=B2=D0=B3. 2019 =D0=B3., =D0=B2 15:25, Vladimir Davydov = =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0=B0=D0=BB(=D0=B0= ): >=20 > On Tue, Aug 27, 2019 at 03:10:47PM +0300, Serge Petrenko wrote: >>=20 >>> 27 =D0=B0=D0=B2=D0=B3. 2019 =D0=B3., =D0=B2 15:04, Vladimir Davydov = =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0=B0=D0=BB(=D0=B0= ): >>>=20 >>> On Tue, Aug 27, 2019 at 02:22:09PM +0300, Serge Petrenko wrote: >>>> This problem is similar to the one fixed in commit >>>> 3c6c1cc96a1a510493c21c472565d4063e403ba2 (lua:fix decimal = comparison >>>> with nil) >>>> We should handle box.NULL the same way. >>>>=20 >>>> Closes #4454 >>>> --- >>>> https://github.com/tarantool/tarantool/issues/4454 >>>> = https://github.com/tarantool/tarantool/tree/sp/gh-4454-decimal-cmp-null >>>>=20 >>>> src/lua/decimal.c | 3 ++- >>>> test/app/decimal.result | 30 ++++++++++++++++++++++++++++++ >>>> test/app/decimal.test.lua | 8 ++++++++ >>>> 3 files changed, 40 insertions(+), 1 deletion(-) >>>>=20 >>>> diff --git a/src/lua/decimal.c b/src/lua/decimal.c >>>> index 23e50ba68..8905a0b9d 100644 >>>> --- a/src/lua/decimal.c >>>> +++ b/src/lua/decimal.c >>>> @@ -235,7 +235,8 @@ static int >>>> ldecimal_eq(struct lua_State *L) >>>> { >>>> assert(lua_gettop(L) =3D=3D 2); >>>> - if (lua_isnil(L, 1) || lua_isnil(L, 2)) { >>>> + if (lua_isnil(L, 1) || lua_isnil(L, 2) || >>>> + luaL_isnull(L, 1) || luaL_isnull(L, 2)) { >>>> lua_pushboolean(L, false); >>>> return 1; >>>> } >>>> diff --git a/test/app/decimal.result b/test/app/decimal.result >>>> index 8251e13d8..90d0984b0 100644 >>>> --- a/test/app/decimal.result >>>> +++ b/test/app/decimal.result >>>> @@ -248,6 +248,36 @@ a <=3D nil >>>> | --- >>>> | - error: '[string "return a <=3D nil "]:1: attempt to compare = decimal with nil' >>>> | ... >>>> +-- and with box.NULL >>>> +-- >>>> +a =3D=3D box.NULL >>>> + | --- >>>> + | - false >>>> + | ... >>>> +a ~=3D box.NULL >>>> + | --- >>>> + | - true >>>> + | ... >>>> +a > box.NULL >>>> + | --- >>>> + | - error: '[string "return a > box.NULL "]:1: expected decimal, = number or string as >>>> + | 1 argument' >>>> + | ... >>>=20 >>> 1 argument? >>=20 >> 1st argument >>=20 >>>=20 >>>> +a < box.NULL >>>> + | --- >>>> + | - error: '[string "return a < box.NULL "]:1: expected decimal, = number or string as >>>> + | 2 argument' >>>> + | ... >>>=20 >>> 2 argument? >>=20 >> 2nd argument >=20 > But in both cases box.NULL is the second argument, isn't it? >=20 > Anyway, looks like it's a different issue, because I get the same > confusing error message while trying to compare a decimal with, say, > a string. We can fix it in a separate patch if we need to. Ah, I see. Sorry for the misunderstanding. Yes, here=E2=80=99s the reason for it: (an extract from https://www.lua.org/manual/5.1/manual.html = ) `a >=3D b is equivalent to b <=3D a. Note that, in the absence of a "le" = metamethod, Lua tries the "lt", assuming that a <=3D b is equivalent to = not (b < a).` `a > b is equivalent to b < a.` So, a > box.NULL actually calls `decimal_lt(box.NULL, a)`. That=E2=80=99s = why argument numbers get messed up. AFAIR you don=E2=80=99t have `__gt` and `__ge` metamethods in lua. I = guess we should just get rid of argument numbers, in error messages here, because I don=E2=80=99t see how this can be = fixed otherwise. >=20 > Pushed the patch to the master branch as is. Thanks! -- Serge Petrenko sergepetrenko@tarantool.org --Apple-Mail=_BA428227-4882-4DFD-982A-7B0293E22A48 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8

27 =D0=B0=D0=B2=D0=B3. 2019 = =D0=B3., =D0=B2 15:25, Vladimir Davydov <vdavydov.dev@gmail.com> =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0= =B0=D0=BB(=D0=B0):

On Tue, Aug = 27, 2019 at 03:10:47PM +0300, Serge Petrenko wrote:

27 =D0=B0=D0=B2=D0=B3. = 2019 =D0=B3., =D0=B2 15:04, Vladimir Davydov <vdavydov.dev@gmail.com> =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0= =B0=D0=BB(=D0=B0):

On Tue, Aug 27, 2019 at = 02:22:09PM +0300, Serge Petrenko wrote:
This problem is similar to the one fixed in = commit
3c6c1cc96a1a510493c21c472565d4063e403ba2 (lua:fix = decimal comparison
with nil)
We should = handle box.NULL the same way.

Closes = #4454
---
https://github.com/tarantool/tarantool/issues/4454
https://github.com/tarantool/tarantool/tree/sp/gh-4454-decimal-= cmp-null

src/lua/decimal.c =         |  3 ++-
test/app/decimal.result   | 30 = ++++++++++++++++++++++++++++++
test/app/decimal.test.lua | =  8 ++++++++
3 files changed, 40 insertions(+), 1 = deletion(-)

diff --git a/src/lua/decimal.c = b/src/lua/decimal.c
index 23e50ba68..8905a0b9d 100644
--- a/src/lua/decimal.c
+++ = b/src/lua/decimal.c
@@ -235,7 +235,8 @@ static int
ldecimal_eq(struct lua_State *L)
{
= assert(lua_gettop(L) =3D=3D 2);
- if = (lua_isnil(L, 1) || lua_isnil(L, 2)) {
+ if = (lua_isnil(L, 1) || lua_isnil(L, 2) ||
+     luaL_isnull= (L, 1) || luaL_isnull(L, 2)) {
= lua_pushboolean(L, false);
return = 1;
}
diff --git a/test/app/decimal.result = b/test/app/decimal.result
index 8251e13d8..90d0984b0 = 100644
--- a/test/app/decimal.result
+++ = b/test/app/decimal.result
@@ -248,6 +248,36 @@ a <=3D = nil
| ---
| - error: '[string "return a = <=3D nil "]:1: attempt to compare decimal with nil'
| = ...
+-- and with box.NULL
+--
+a= =3D=3D box.NULL
+ | ---
+ | - false
+ | ...
+a ~=3D box.NULL
+ | = ---
+ | - true
+ | ...
+a > = box.NULL
+ | ---
+ | - error: '[string = "return a > box.NULL "]:1: expected decimal, number or string as
+ |     1 argument'
+ | = ...

1 argument?

1st argument


+a < box.NULL
+ | ---
+ | - error: '[string "return a < box.NULL "]:1: expected = decimal, number or string as
+ |     2 = argument'
+ | ...

2 argument?

2nd = argument

But in both cases box.NULL is the second argument, isn't = it?

Anyway, looks = like it's a different issue, because I get the same
confusing error message while = trying to compare a decimal with, say,
a string. We can fix it in a separate patch if we need = to.

Ah, I = see. Sorry for the misunderstanding.
Yes, here=E2=80=99s the = reason for it:
`a >=3D b is equivalent to b <=3D a. Note = that, in the absence of a "le" metamethod, Lua tries the "lt", assuming = that a <=3D b is equivalent to not (b < = a).`
`a > b is equivalent = to b < a.`

So, a > box.NULL = actually calls `decimal_lt(box.NULL, a)`. That=E2=80=99s why argument = numbers get messed up.
AFAIR you = don=E2=80=99t have `__gt` and `__ge` metamethods in lua. I guess we = should just get rid of argument numbers,
in error messages here, because I don=E2=80=99t see how this = can be fixed otherwise.


Pushed the patch to the master = branch as is.

Thanks!


--
Serge = Petrenko


= --Apple-Mail=_BA428227-4882-4DFD-982A-7B0293E22A48--