Merge pull request #112

Use a random integer as the starting value for 'rev'
uatuko · Oct 20, 2024 · 96d61f7 · 96d61f7
2 parents 9a98d53 + 25c8df4
commit 96d61f7
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Showing 7 changed files with 61 additions and 8 deletions.
diff --git a/src/db/CMakeLists.txt b/src/db/CMakeLists.txt
@@ -1,6 +1,7 @@
 add_library(db)
 target_sources(db
 	PRIVATE
+		detail.cpp
 		pg.cpp
 		principals.cpp
 		tuples.cpp
@@ -9,13 +10,15 @@ target_sources(db
 		FILE_SET headers TYPE HEADERS
 		FILES
 			config.h
+			db.h
 			pg.h
 			principals.h
 			tuples.h
 			tuplets.h
 	PRIVATE
 		FILE_SET private_headers TYPE HEADERS
 		FILES
+			detail.h
 			common.h
 )
 

diff --git a/src/db/detail.cpp b/src/db/detail.cpp
@@ -0,0 +1,14 @@
+#include "detail.h"
+
+#include <random>
+
+namespace db {
+namespace detail {
+int rand() {
+	static std::random_device rd;
+	static std::mt19937       g(rd());
+
+	return g();
+}
+} // namespace detail
+} // namespace db
diff --git a/src/db/detail.h b/src/db/detail.h
@@ -0,0 +1,7 @@
+#pragma once
+
+namespace db {
+namespace detail {
+int rand();
+} // namespace detail
+} // namespace db
diff --git a/src/db/principals.cpp b/src/db/principals.cpp
@@ -5,14 +5,16 @@
 
 #include "err/errors.h"
 
+#include "detail.h"
+
 namespace db {
-Principal::Principal(const Principal::Data &data) noexcept : _data(data), _rev(0) {
+Principal::Principal(const Principal::Data &data) noexcept : _data(data), _rev(detail::rand()) {
 	if (_data.id.empty()) {
 		_data.id = xid::next();
 	}
 }
 
-Principal::Principal(Data &&data) noexcept : _data(std::move(data)), _rev(0) {
+Principal::Principal(Data &&data) noexcept : _data(std::move(data)), _rev(detail::rand()) {
 	if (_data.id.empty()) {
 		_data.id = xid::next();
 	}

diff --git a/src/db/principals_test.cpp b/src/db/principals_test.cpp
@@ -235,17 +235,29 @@ TEST_F(db_PrincipalsTest, retrieve) {
 }
 
 TEST_F(db_PrincipalsTest, rev) {
+	// Success: revision
+	{
+		const db::Principal::Data data{
+			.id = "id:db_PrincipalsTest.rev",
+		};
+
+		db::Principal pl(data), pr(data);
+		EXPECT_FALSE(pl == pr);
+		EXPECT_FALSE(pl.rev() == pr.rev());
+		EXPECT_EQ(pl.id(), pr.id());
+	}
+
 	// Success: revision increment
 	{
 		db::Principal principal({
 			.id = "id:db_PrincipalsTest.rev",
 		});
 
 		ASSERT_NO_THROW(principal.store());
-		EXPECT_EQ(0, principal.rev());
 
+		auto expected = principal.rev() + 1;
 		ASSERT_NO_THROW(principal.store());
-		EXPECT_EQ(1, principal.rev());
+		EXPECT_EQ(expected, principal.rev());
 	}
 
 	// Error: revision mismatch

diff --git a/src/db/tuples.cpp b/src/db/tuples.cpp
@@ -6,15 +6,16 @@
 #include "err/errors.h"
 
 #include "common.h"
+#include "detail.h"
 
 namespace db {
 Tuple::Tuple(const Tuple::Data &data) noexcept :
-	_data(data), _id(), _rev(0), _lHash(), _rHash(), _ridL(), _ridR() {
+	_data(data), _id(), _rev(detail::rand()), _lHash(), _rHash(), _ridL(), _ridR() {
 	sanitise();
 }
 
 Tuple::Tuple(Tuple::Data &&data) noexcept :
-	_data(std::move(data)), _id(), _rev(0), _lHash(), _rHash(), _ridL(), _ridR() {
+	_data(std::move(data)), _id(), _rev(detail::rand()), _lHash(), _rHash(), _ridL(), _ridR() {
 	sanitise();
 }
 

diff --git a/src/db/tuples_test.cpp b/src/db/tuples_test.cpp
@@ -494,6 +494,20 @@ TEST_F(db_TuplesTest, retrieve) {
 }
 
 TEST_F(db_TuplesTest, rev) {
+	// Success: revision
+	{
+		const db::Tuple::Data data{
+			.lEntityId   = "left",
+			.lEntityType = "db_TuplesTest.rev",
+			.relation    = "relation",
+			.rEntityId   = "right",
+			.rEntityType = "db_TuplesTest.rev",
+		};
+
+		db::Tuple tl(data), tr(data);
+		EXPECT_FALSE(tl.rev() == tr.rev());
+	}
+
 	// Success: revision increment
 	{
 		db::Tuple tuple({
@@ -505,10 +519,10 @@ TEST_F(db_TuplesTest, rev) {
 		});
 
 		ASSERT_NO_THROW(tuple.store());
-		EXPECT_EQ(0, tuple.rev());
 
+		auto expected = tuple.rev() + 1;
 		ASSERT_NO_THROW(tuple.store());
-		EXPECT_EQ(1, tuple.rev());
+		EXPECT_EQ(expected, tuple.rev());
 	}
 
 	// Error: revision mismatch