[Tarantool-patches] [PATCH] lua: introduce function to check that passed value is uuid

[olegrok@tarantool.org]

From: Oleg Babin <babinoleg@mail.ru>

We've already have is_decimal function that checks allowed value
is decimal. After tarantool started to support UUID type it will
be quite often case to check that some value has UUID type as
well. This patch introduces "is_uuid" function for this purpose.

Closes #5171

@TarantoolBot document
Title: uuid.is_uuid

is_uuid function returns "true" if specified value has uuid type
and "false" otherwise.
---
Issue: https://github.com/tarantool/tarantool/issues/5171
Branch: https://github.com/tarantool/tarantool/tree/olegrok/5171-is_uuid

@Changelog:
  * Introduce function to check that specified value has UUID
  type (gh-5171). 

 src/lua/uuid.lua       | 15 ++++++++++-----
 test/app/uuid.result   | 19 +++++++++++++++++++
 test/app/uuid.test.lua | 10 ++++++++++
 3 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/src/lua/uuid.lua b/src/lua/uuid.lua
index 5d19a4408..42016601d 100644
--- a/src/lua/uuid.lua
+++ b/src/lua/uuid.lua
@@ -26,8 +26,12 @@ local uuid_t = ffi.typeof('struct tt_uuid')
 local UUID_STR_LEN = 36
 local UUID_LEN = ffi.sizeof(uuid_t)
 
+local is_uuid = function(value)
+    return ffi.istype(uuid_t, value)
+end
+
 local uuid_tostring = function(uu)
-    if not ffi.istype(uuid_t, uu) then
+    if not is_uuid(uu) then
         return error('Usage: uuid:str()')
     end
     return ffi.string(builtin.tt_uuid_str(uu), UUID_STR_LEN)
@@ -56,7 +60,7 @@ local need_bswap = function(order)
 end
 
 local uuid_tobin = function(uu, byteorder)
-    if not ffi.istype(uuid_t, uu) then
+    if not is_uuid(uu) then
         return error('Usage: uuid:bin([byteorder])')
     end
     if need_bswap(byteorder) then
@@ -81,17 +85,17 @@ local uuid_frombin = function(bin, byteorder)
 end
 
 local uuid_isnil = function(uu)
-    if not ffi.istype(uuid_t, uu) then
+    if not is_uuid(uu) then
         return error('Usage: uuid:isnil()')
     end
     return builtin.tt_uuid_is_nil(uu)
 end
 
 local uuid_eq = function(lhs, rhs)
-    if not ffi.istype(uuid_t, rhs) then
+    if not is_uuid(rhs) then
         return false
     end
-    if not ffi.istype(uuid_t, lhs) then
+    if not is_uuid(lhs) then
         return error('Usage: uuid == var')
     end
     return builtin.tt_uuid_is_equal(lhs, rhs)
@@ -133,6 +137,7 @@ return setmetatable({
     frombin     = uuid_frombin;
     bin         = uuid_new_bin;   -- optimized shortcut for new():bin()
     str         = uuid_new_str;   -- optimized shortcut for new():str()
+    is_uuid     = is_uuid;
 }, {
     __call = uuid_new; -- shortcut for new()
 })
diff --git a/test/app/uuid.result b/test/app/uuid.result
index 751865e5f..9fe0e7fb4 100644
--- a/test/app/uuid.result
+++ b/test/app/uuid.result
@@ -272,6 +272,25 @@ uu.str()
 uu = nil
 ---
 ...
+--
+-- gh-5171: is_uuid function
+--
+uuid.is_uuid(uuid.new())
+---
+- true
+...
+uuid.is_uuid(uuid.new():str())
+---
+- false
+...
+uuid.is_uuid(1)
+---
+- false
+...
+uuid.is_uuid(require('decimal').new('123'))
+---
+- false
+...
 uuid = nil
 ---
 ...
diff --git a/test/app/uuid.test.lua b/test/app/uuid.test.lua
index ac125cddc..47a96f3c6 100644
--- a/test/app/uuid.test.lua
+++ b/test/app/uuid.test.lua
@@ -98,6 +98,16 @@ uu.bin()
 uu.str()
 
 uu = nil
+
+--
+-- gh-5171: is_uuid function
+--
+
+uuid.is_uuid(uuid.new())
+uuid.is_uuid(uuid.new():str())
+uuid.is_uuid(1)
+uuid.is_uuid(require('decimal').new('123'))
+
 uuid = nil
 
 test_run:cmd("clear filter")
-- 
2.23.0