[Tarantool-patches] [PATCH v2 04/10] box/error: introduce box.error.set() method

[Nikita Pettik]

box.error.set(err) sets err to instance's diagnostics area. Argument err
is supposed to be instance of error object. This method is required
since we are going to avoid adding created via box.error.new() errors to
Tarantool's diagnostic area.

Needed for #1148
Part of #4778
---
 src/box/lua/error.cc    | 14 ++++++++++++++
 src/lua/error.c         |  2 +-
 src/lua/error.h         |  3 +++
 test/box/error.result   | 36 ++++++++++++++++++++++++++++++++++++
 test/box/error.test.lua | 15 +++++++++++++++
 5 files changed, 69 insertions(+), 1 deletion(-)

diff --git a/src/box/lua/error.cc b/src/box/lua/error.cc
index fc53a40f4..640e33910 100644
--- a/src/box/lua/error.cc
+++ b/src/box/lua/error.cc
@@ -154,6 +154,16 @@ luaT_error_clear(lua_State *L)
 	return 0;
 }
 
+static int
+luaT_error_set(lua_State *L)
+{
+	if (lua_gettop(L) == 0)
+		return luaL_error(L, "Usage: box.error.set(error)");
+	struct error *e = luaL_checkerror(L, 1);
+	diag_set_error(&fiber()->diag, e);
+	return 0;
+}
+
 static int
 lbox_errinj_set(struct lua_State *L)
 {
@@ -268,6 +278,10 @@ box_lua_error_init(struct lua_State *L) {
 			lua_pushcfunction(L, luaT_error_new);
 			lua_setfield(L, -2, "new");
 		}
+		{
+			lua_pushcfunction(L, luaT_error_set);
+			lua_setfield(L, -2, "set");
+		}
 		lua_setfield(L, -2, "__index");
 	}
 	lua_setmetatable(L, -2);
diff --git a/src/lua/error.c b/src/lua/error.c
index d82e78dc4..18a990a88 100644
--- a/src/lua/error.c
+++ b/src/lua/error.c
@@ -53,7 +53,7 @@ luaL_iserror(struct lua_State *L, int narg)
 	return e;
 }
 
-static struct error *
+struct error *
 luaL_checkerror(struct lua_State *L, int narg)
 {
 	struct error *error = luaL_iserror(L, narg);
diff --git a/src/lua/error.h b/src/lua/error.h
index 64fa5eba3..16cdaf7fe 100644
--- a/src/lua/error.h
+++ b/src/lua/error.h
@@ -65,6 +65,9 @@ luaT_pusherror(struct lua_State *L, struct error *e);
 struct error *
 luaL_iserror(struct lua_State *L, int narg);
 
+struct error *
+luaL_checkerror(struct lua_State *L, int narg);
+
 void
 tarantool_lua_error_init(struct lua_State *L);
 
diff --git a/test/box/error.result b/test/box/error.result
index 9b6c8b462..31b2ce52b 100644
--- a/test/box/error.result
+++ b/test/box/error.result
@@ -436,6 +436,42 @@ test_run:cmd("setopt delimiter ''");
  | ---
  | - true
  | ...
+
+-- gh-4778: don't add created via box.error.new() errors to
+-- Tarantool's diagnostic area.
+--
+err = box.error.new({code = 111, reason = "cause"})
+ | ---
+ | ...
+assert(box.error.last() ~= err)
+ | ---
+ | - error: assertion failed!
+ | ...
+box.error.set(err)
+ | ---
+ | ...
+assert(box.error.last() == err)
+ | ---
+ | - true
+ | ...
+-- Consider wrong or tricky inputs to box.error.set()
+--
+box.error.set(1)
+ | ---
+ | - error: 'Invalid argument #1 (error expected, got number)'
+ | ...
+box.error.set(nil)
+ | ---
+ | - error: 'Invalid argument #1 (error expected, got nil)'
+ | ...
+box.error.set(box.error.last())
+ | ---
+ | ...
+assert(box.error.last() == err)
+ | ---
+ | - true
+ | ...
+
 space:drop()
  | ---
  | ...
diff --git a/test/box/error.test.lua b/test/box/error.test.lua
index d16cc5672..81591ea7e 100644
--- a/test/box/error.test.lua
+++ b/test/box/error.test.lua
@@ -77,4 +77,19 @@ end;
 t;
 
 test_run:cmd("setopt delimiter ''");
+
+-- gh-4778: don't add created via box.error.new() errors to
+-- Tarantool's diagnostic area.
+--
+err = box.error.new({code = 111, reason = "cause"})
+assert(box.error.last() ~= err)
+box.error.set(err)
+assert(box.error.last() == err)
+-- Consider wrong or tricky inputs to box.error.set()
+--
+box.error.set(1)
+box.error.set(nil)
+box.error.set(box.error.last())
+assert(box.error.last() == err)
+
 space:drop()
-- 
2.17.1