fix for #1005: upsert can update primary key

I've added default tuple fields check against primary index key.
Primary key can yet be updated, but an old key will be
silently used anyway (copy used from update object).

Added tests.

ps. maybe it is better to validate upsert ops on execute?

src/box/sophia_engine.cc

@@ -190,9 +190,21 @@ SophiaSpace::executeUpsert(struct txn *txn, struct space *space,
                            struct request *request)
 {
 	SophiaIndex *index = (SophiaIndex *)index_find(space, request->index_id);
+
+	/* validate upsert key */
 	const char *key = request->key;
 	uint32_t part_count = mp_decode_array(&key);
 	primary_key_validate(index->key_def, key, part_count);
+
+	/* validate default tuple */
+	space_validate_tuple_raw(space, request->tuple);
+	tuple_field_count_validate(space->format, request->tuple);
+
+	int size = request->tuple_end - request->tuple;
+	key = tuple_field_raw(request->tuple, size,
+	                      index->key_def->parts[0].fieldno);
+	primary_key_validate(index->key_def, key, index->key_def->part_count);
+
 	index->upsert(key,
 	              request->ops,
 	              request->ops_end,

test/sophia/upsert.result

@@ -1045,3 +1045,34 @@ t
 space:drop()
 ---
 ...
+-- upsert default tuple constraint
+space = box.schema.space.create('test', { engine = 'sophia' })
+---
+...
+index = space:create_index('primary', { type = 'tree', parts = {1, 'num', 2, 'num'} })
+---
+...
+space:upsert({0, 0}, {{'+', 3, 1}}, {0, 'key', 0})
+---
+- error: 'Supplied key type of part 1 does not match index part type: expected NUM'
+...
+space:drop()
+---
+...
+-- upsert primary key modify (skipped)
+space = box.schema.space.create('test', { engine = 'sophia' })
+---
+...
+index = space:create_index('primary', { type = 'tree', parts = {1, 'num'} })
+---
+...
+space:upsert({0}, {{'+', 1, 1}, {'+', 2, 1}}, {0, 0})
+---
+...
+space:get({0})
+---
+- [0, 1]
+...
+space:drop()
+---
+...

test/sophia/upsert.test.lua

@@ -54,3 +54,18 @@ t = {}
 for key = 1, 100 do table.insert(t, space:get({key, key})) end
 t
 space:drop()
+
+
+-- upsert default tuple constraint
+space = box.schema.space.create('test', { engine = 'sophia' })
+index = space:create_index('primary', { type = 'tree', parts = {1, 'num', 2, 'num'} })
+space:upsert({0, 0}, {{'+', 3, 1}}, {0, 'key', 0})
+space:drop()
+
+
+-- upsert primary key modify (skipped)
+space = box.schema.space.create('test', { engine = 'sophia' })
+index = space:create_index('primary', { type = 'tree', parts = {1, 'num'} })
+space:upsert({0}, {{'+', 1, 1}, {'+', 2, 1}}, {0, 0})
+space:get({0})
+space:drop()