feat: expand index

src/index.zig

@@ -1423,3 +1423,157 @@ test "ForeignKeySet add remove save load round trip" {
     try std.testing.expect(!third.has("customer_id"));
 }
 
+test "ForeignKeySet.load rejects a corrupted onDelete byte instead of accepting garbage" {
+    const allocator = std.testing.allocator;
+    var tmp = std.testing.tmpDir(.{});
+    defer tmp.cleanup();
+    const dbPath = try tmp.dir.realpathAlloc(allocator, ".");
+    defer allocator.free(dbPath);
+
+    var db = try Db.open(allocator, dbPath, .{});
+    defer db.close();
+
+    var set = try ForeignKeySet.load(allocator, &db, "orders");
+    defer set.deinit();
+    try set.add("customer_id", "customers", "__pk", .restrict);
+    try set.save(&db, "orders");
+
+    const key = try foreignKeyMetaKey(allocator, "orders");
+    defer allocator.free(key);
+    const raw = try db.get(allocator, key) orelse return error.TestUnexpectedResult;
+    defer allocator.free(raw);
+
+    // Flip the trailing onDelete byte to a value neither `restrict` (0)
+    // nor `cascade` (1) can ever legitimately be - same "malformed input
+    // is rejected, not silently coerced" contract every other decoder in
+    // this file already gives length-prefixed strings.
+    const corrupted = try allocator.dupe(u8, raw);
+    defer allocator.free(corrupted);
+    corrupted[corrupted.len - 1] = 0xFF;
+    try db.put(key, corrupted);
+
+    try std.testing.expectError(error.Malformed, ForeignKeySet.load(allocator, &db, "orders"));
+}
+
+test "ReferencedBySet add replaces an existing (childTable, childField) pair instead of duplicating it" {
+    const allocator = std.testing.allocator;
+    var tmp = std.testing.tmpDir(.{});
+    defer tmp.cleanup();
+    const dbPath = try tmp.dir.realpathAlloc(allocator, ".");
+    defer allocator.free(dbPath);
+
+    var db = try Db.open(allocator, dbPath, .{});
+    defer db.close();
+
+    var set = try ReferencedBySet.load(allocator, &db, "customers");
+    defer set.deinit();
+    try std.testing.expectEqual(@as(usize, 0), set.specs.items.len);
+
+    try set.add("orders", "customer_id", "__pk", .restrict);
+    try set.add("orders", "customer_id", "__pk", .restrict);
+    try std.testing.expectEqual(@as(usize, 1), set.specs.items.len);
+    try set.add("line_items", "customer_id", "__pk", .cascade);
+    try std.testing.expectEqual(@as(usize, 2), set.specs.items.len);
+    try set.save(&db, "customers");
+
+    var reloaded = try ReferencedBySet.load(allocator, &db, "customers");
+    defer reloaded.deinit();
+    try std.testing.expectEqual(@as(usize, 2), reloaded.specs.items.len);
+    for (reloaded.specs.items) |spec| {
+        if (std.mem.eql(u8, spec.childTable, "line_items")) {
+            try std.testing.expectEqual(OnDelete.cascade, spec.onDelete);
+        } else {
+            try std.testing.expectEqual(OnDelete.restrict, spec.onDelete);
+        }
+    }
+
+    // Re-adding the same pair under a different refField AND onDelete mode
+    // replaces both in place rather than accumulating a second, now-stale
+    // entry.
+    try reloaded.add("orders", "customer_id", "email", .cascade);
+    try std.testing.expectEqual(@as(usize, 2), reloaded.specs.items.len);
+    var sawOrders = false;
+    for (reloaded.specs.items) |spec| {
+        if (std.mem.eql(u8, spec.childTable, "orders")) {
+            sawOrders = true;
+            try std.testing.expectEqualStrings("email", spec.refField);
+            try std.testing.expectEqual(OnDelete.cascade, spec.onDelete);
+        }
+    }
+    try std.testing.expect(sawOrders);
+
+    try std.testing.expect(reloaded.remove("orders", "customer_id"));
+    try std.testing.expect(!reloaded.remove("orders", "customer_id"));
+    try reloaded.save(&db, "customers");
+
+    var third = try ReferencedBySet.load(allocator, &db, "customers");
+    defer third.deinit();
+    try std.testing.expectEqual(@as(usize, 1), third.specs.items.len);
+    try std.testing.expectEqualStrings("line_items", third.specs.items[0].childTable);
+}
+
+test "CheckConstraintSet add remove save load round trip" {
+    const allocator = std.testing.allocator;
+    var tmp = std.testing.tmpDir(.{});
+    defer tmp.cleanup();
+    const dbPath = try tmp.dir.realpathAlloc(allocator, ".");
+    defer allocator.free(dbPath);
+
+    var db = try Db.open(allocator, dbPath, .{});
+    defer db.close();
+
+    var set = try CheckConstraintSet.load(allocator, &db, "orders");
+    defer set.deinit();
+    try std.testing.expectEqual(@as(usize, 0), set.specs.items.len);
+
+    try set.add("qty_positive", "qty gt 0");
+    try set.add("qty_positive", "qty gt 100");
+    try std.testing.expectEqual(@as(usize, 1), set.specs.items.len);
+    try set.save(&db, "orders");
+
+    var reloaded = try CheckConstraintSet.load(allocator, &db, "orders");
+    defer reloaded.deinit();
+    try std.testing.expect(reloaded.has("qty_positive"));
+    try std.testing.expect(!reloaded.has("missing"));
+    const spec = reloaded.find("qty_positive").?;
+    try std.testing.expectEqualStrings("qty gt 0", spec.source);
+
+    try std.testing.expect(reloaded.remove("qty_positive"));
+    try std.testing.expect(!reloaded.remove("qty_positive"));
+    try reloaded.save(&db, "orders");
+
+    var third = try CheckConstraintSet.load(allocator, &db, "orders");
+    defer third.deinit();
+    try std.testing.expect(!third.has("qty_positive"));
+}
+
+test "ForeignKeySet, UniqueSet, and IndexSet on the same table never collide" {
+    const allocator = std.testing.allocator;
+    var tmp = std.testing.tmpDir(.{});
+    defer tmp.cleanup();
+    const dbPath = try tmp.dir.realpathAlloc(allocator, ".");
+    defer allocator.free(dbPath);
+
+    var db = try Db.open(allocator, dbPath, .{});
+    defer db.close();
+
+    var indexes = try IndexSet.load(allocator, &db, "orders");
+    defer indexes.deinit();
+    try indexes.add("customer_id");
+    try indexes.save(&db, "orders");
+
+    var unique = try UniqueSet.load(allocator, &db, "orders");
+    defer unique.deinit();
+    try unique.add("order_number");
+    try unique.save(&db, "orders");
+
+    var fkeys = try ForeignKeySet.load(allocator, &db, "orders");
+    defer fkeys.deinit();
+    try fkeys.add("customer_id", "customers", "__pk", .restrict);
+    try fkeys.save(&db, "orders");
+
+    var checks = try CheckConstraintSet.load(allocator, &db, "orders");
+    defer checks.deinit();
+    try checks.add("qty_positive", "qty gt 0");
+    try checks.save(&db, "orders");
+