[tarantool-patches] [PATCH] sql: swap FK masks during altering of space

[Nikita Pettik <korablev@tarantool.org>]

It was forgotten to swap old and new mask (holding fields involved into
foreign key relation) during space alteration (lists of object
representing FK metadata are swapped successfully). Since mask is vital
and depending on its value different byte-codes implementing SQL query
can be produced, this mistake resulted in assertion fault in debug build
and wrong constraint check in release build. Let's fix this bug and swap
masks as well as foreign key lists.

Closes #4495
---
Branch: https://github.com/tarantool/tarantool/tree/np/gh-4495-swap-fk-mask
Issue: https://github.com/tarantool/tarantool/issues/4495

 src/box/alter.cc               |  1 +
 test/sql/foreign-keys.result   | 38 ++++++++++++++++++++++++++++++++++++++
 test/sql/foreign-keys.test.lua | 15 +++++++++++++++
 3 files changed, 54 insertions(+)

diff --git a/src/box/alter.cc b/src/box/alter.cc
index c0780d6da..499df1ca2 100644
--- a/src/box/alter.cc
+++ b/src/box/alter.cc
@@ -619,6 +619,7 @@ space_swap_fk_constraints(struct space *new_space, struct space *old_space)
 		   &old_space->child_fk_constraint);
 	rlist_swap(&new_space->parent_fk_constraint,
 		   &old_space->parent_fk_constraint);
+	SWAP(new_space->fk_constraint_mask, old_space->fk_constraint_mask);
 }
 
 /**
diff --git a/test/sql/foreign-keys.result b/test/sql/foreign-keys.result
index b8ff8f145..29538e816 100644
--- a/test/sql/foreign-keys.result
+++ b/test/sql/foreign-keys.result
@@ -457,5 +457,43 @@ t1:drop()
 t2:drop()
 ---
 ...
+-- gh-4495: space alter resulted in foreign key mask reset.
+-- Which in turn led to wrong byte-code generation. Make sure
+-- that alter of space doesn't affect result of query execution.
+--
+box.execute("CREATE TABLE t (id TEXT PRIMARY KEY, a INTEGER NOT NULL);")
+---
+- row_count: 1
+...
+box.execute("CREATE TABLE s (t_id TEXT PRIMARY KEY, a INTEGER NOT NULL, FOREIGN KEY(t_id) REFERENCES t(id) ON DELETE CASCADE);")
+---
+- row_count: 1
+...
+box.space.T:insert({'abc', 1})
+---
+- ['abc', 1]
+...
+box.space.S:insert({'abc', 1})
+---
+- ['abc', 1]
+...
+box.execute("CREATE INDEX i ON s (t_id);")
+---
+- row_count: 1
+...
+box.execute("DELETE FROM t WHERE id = 'abc';")
+---
+- row_count: 1
+...
+box.space.T:select()
+---
+- []
+...
+box.space.S:drop()
+---
+...
+box.space.T:drop()
+---
+...
 --- Clean-up SQL DD hash.
 -test_run:cmd('restart server default with cleanup=1')
diff --git a/test/sql/foreign-keys.test.lua b/test/sql/foreign-keys.test.lua
index 4ac5999d7..d2dd88d28 100644
--- a/test/sql/foreign-keys.test.lua
+++ b/test/sql/foreign-keys.test.lua
@@ -194,5 +194,20 @@ box.execute("ALTER TABLE t2 ADD CONSTRAINT fk FOREIGN KEY (id) REFERENCES t1;")
 t1:drop()
 t2:drop()
 
+-- gh-4495: space alter resulted in foreign key mask reset.
+-- Which in turn led to wrong byte-code generation. Make sure
+-- that alter of space doesn't affect result of query execution.
+--
+box.execute("CREATE TABLE t (id TEXT PRIMARY KEY, a INTEGER NOT NULL);")
+box.execute("CREATE TABLE s (t_id TEXT PRIMARY KEY, a INTEGER NOT NULL, FOREIGN KEY(t_id) REFERENCES t(id) ON DELETE CASCADE);")
+box.space.T:insert({'abc', 1})
+box.space.S:insert({'abc', 1})
+box.execute("CREATE INDEX i ON s (t_id);")
+box.execute("DELETE FROM t WHERE id = 'abc';")
+box.space.T:select()
+
+box.space.S:drop()
+box.space.T:drop()
+
 --- Clean-up SQL DD hash.
 -test_run:cmd('restart server default with cleanup=1')
-- 
2.15.1