#1448 Fix issue with using query.find(flecs::entity, ...) and QueryMa…

…tchEmptyTables
SanderMertens · Nov 22, 2024 · e3219d7 · e3219d7
1 parent 2a23e6e
commit e3219d7
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Showing 5 changed files with 49 additions and 13 deletions.
diff --git a/distr/flecs.h b/distr/flecs.h
@@ -26153,9 +26153,6 @@ struct each_delegate : public delegate {
     static void invoke_callback(
         ecs_iter_t *iter, const Func& func, size_t i, Args... comps) 
     {
-        ecs_assert(iter->count > 0, ECS_INVALID_OPERATION,
-            "no entities returned, use each() without flecs::entity argument");
-
         func(flecs::entity(iter->world, iter->entities[i]),
             (ColumnType< remove_reference_t<Components> >(iter, comps, i)
                 .get_row())...);
@@ -26272,9 +26269,6 @@ struct find_delegate : public delegate {
         size_t count = static_cast<size_t>(iter->count);
         flecs::entity result;
 
-        ecs_assert(count > 0, ECS_INVALID_OPERATION,
-            "no entities returned, use find() without flecs::entity argument");
-
         for (size_t i = 0; i < count; i ++) {
             if (func(flecs::entity(world, iter->entities[i]),
                 (ColumnType< remove_reference_t<Components> >(iter, comps, i)

diff --git a/include/flecs/addons/cpp/delegate.hpp b/include/flecs/addons/cpp/delegate.hpp
@@ -301,9 +301,6 @@ struct each_delegate : public delegate {
     static void invoke_callback(
         ecs_iter_t *iter, const Func& func, size_t i, Args... comps) 
     {
-        ecs_assert(iter->count > 0, ECS_INVALID_OPERATION,
-            "no entities returned, use each() without flecs::entity argument");
-
         func(flecs::entity(iter->world, iter->entities[i]),
             (ColumnType< remove_reference_t<Components> >(iter, comps, i)
                 .get_row())...);
@@ -420,9 +417,6 @@ struct find_delegate : public delegate {
         size_t count = static_cast<size_t>(iter->count);
         flecs::entity result;
 
-        ecs_assert(count > 0, ECS_INVALID_OPERATION,
-            "no entities returned, use find() without flecs::entity argument");
-
         for (size_t i = 0; i < count; i ++) {
             if (func(flecs::entity(world, iter->entities[i]),
                 (ColumnType< remove_reference_t<Components> >(iter, comps, i)

diff --git a/test/cpp/project.json b/test/cpp/project.json
@@ -674,6 +674,8 @@
                 "find",
                 "find_not_found",
                 "find_w_entity",
+                "find_w_match_empty_tables",
+                "find_w_entity_w_match_empty_tables",
                 "optional_pair_term",
                 "empty_tables_each",
                 "empty_tables_each_w_entity",

diff --git a/test/cpp/src/Query.cpp b/test/cpp/src/Query.cpp
@@ -523,6 +523,42 @@ void Query_find_w_entity(void) {
     test_assert(r == e2);
 }
 
+void Query_find_w_match_empty_tables(void) {
+    flecs::world ecs;
+
+    auto e1 = ecs.entity().set<Position>({10, 20}).add<Velocity>();
+    e1.destruct(); // creates empty table
+    auto e2 = ecs.entity().set<Position>({20, 30});
+
+    auto q = ecs.query_builder<Position>()
+        .query_flags(EcsQueryMatchEmptyTables)
+        .build();
+
+    auto r = q.find([](Position& p) {
+        return p.x == 20;
+    });
+
+    test_assert(r == e2);
+}
+
+void Query_find_w_entity_w_match_empty_tables(void) {
+    flecs::world ecs;
+
+    auto e1 = ecs.entity().set<Position>({10, 20}).add<Velocity>();
+    e1.destruct(); // creates empty table
+    auto e2 = ecs.entity().set<Position>({20, 30});
+
+    auto q = ecs.query_builder<Position>()
+        .query_flags(EcsQueryMatchEmptyTables)
+        .build();
+
+    auto r = q.find([](flecs::entity e, Position& p) {
+        return p.x == 20;
+    });
+
+    test_assert(r == e2);
+}
+
 // Generic lambdas are a C++14 feature.
 
 struct GenericLambdaFindEntity {

diff --git a/test/cpp/src/main.cpp b/test/cpp/src/main.cpp
@@ -650,6 +650,8 @@ void Query_iter_get_pair_w_id(void);
 void Query_find(void);
 void Query_find_not_found(void);
 void Query_find_w_entity(void);
+void Query_find_w_match_empty_tables(void);
+void Query_find_w_entity_w_match_empty_tables(void);
 void Query_optional_pair_term(void);
 void Query_empty_tables_each(void);
 void Query_empty_tables_each_w_entity(void);
@@ -3919,6 +3921,14 @@ bake_test_case Query_testcases[] = {
         "find_w_entity",
         Query_find_w_entity
     },
+    {
+        "find_w_match_empty_tables",
+        Query_find_w_match_empty_tables
+    },
+    {
+        "find_w_entity_w_match_empty_tables",
+        Query_find_w_entity_w_match_empty_tables
+    },
     {
         "optional_pair_term",
         Query_optional_pair_term
@@ -6908,7 +6918,7 @@ static bake_test_suite suites[] = {
         "Query",
         NULL,
         NULL,
-        116,
+        118,
         Query_testcases
     },
     {