tests: regression test that every PrintRegion/Object field is in a preset key list (#13466)

Co-authored-by: Rodrigo Faselli <162915171+RF47@users.noreply.github.com>

tests/libslic3r/CMakeLists.txt

@@ -19,6 +19,7 @@ add_executable(${_TEST_NAME}_tests
     test_preset_setting_id.cpp
     test_preset_diff.cpp
     test_vendor_cache.cpp
+    test_preset_options.cpp
     test_elephant_foot_compensation.cpp
     test_fill_corner_smoothing.cpp
     test_filament_mixer.cpp

tests/libslic3r/test_preset_options.cpp

@@ -0,0 +1,70 @@
+// Regression test for the "option in def + UI but missing from preset key list"
+// crash class.
+//
+// The print preset's DynamicPrintConfig is seeded with only the keys returned by
+// Preset::print_options() (PresetBundle.cpp). A field added to PrintRegionConfig
+// or PrintObjectConfig and registered via print_config_def plus a TabPrint
+// optgroup, but left out of print_options(), still gets its control built; on tab
+// activation reload_config -> get_config_value dispatches to opt_bool/opt_int on a
+// DynamicPrintConfig with no entry for the key, and the accessor null-derefs the
+// result of option<T>(key).
+//
+// The invariant asserted here is the inverse: every key declared on
+// PrintRegionConfig and PrintObjectConfig appears in Preset::print_options() or
+// Preset::filament_options(), the two preset key lists that seed a print preset's
+// DynamicConfig.
+
+#include <catch2/catch_all.hpp>
+
+#include "libslic3r/Preset.hpp"
+#include "libslic3r/PrintConfig.hpp"
+
+#include <set>
+
+using namespace Slic3r;
+
+namespace {
+
+// Deprecated keys renamed in handle_legacy() (ironing_direction ->
+// ironing_angle, wall_infill_order -> wall_sequence); neither is in a
+// preset list. Register new options in a preset list, not here.
+const std::set<std::string> kDeprecatedRegionFields = {
+    "ironing_direction",
+    "wall_infill_order",
+};
+
+void check_keys_are_in_a_preset(const t_config_option_keys& keys, const std::string& class_name)
+{
+    REQUIRE_FALSE(keys.empty());
+    const auto& print_options    = Preset::print_options();
+    const auto& filament_options = Preset::filament_options();
+    const std::set<std::string> in_print(print_options.begin(), print_options.end());
+    const std::set<std::string> in_filament(filament_options.begin(), filament_options.end());
+    for (const std::string& key : keys) {
+        DYNAMIC_SECTION(class_name << "::" << key)
+        {
+            INFO("'" << key << "' on " << class_name
+                     << " is missing from "
+                        "Preset::print_options()/filament_options(); add it to "
+                        "s_Preset_print_options (or s_Preset_filament_options) in Preset.cpp.");
+            const bool registered = in_print.count(key) || in_filament.count(key) || kDeprecatedRegionFields.count(key);
+            REQUIRE(registered);
+        }
+    }
+}
+
+} // namespace
+
+// Bodies are laid out like the rest of the test suite rather than collapsed
+// onto the brace line.
+// clang-format off
+TEST_CASE("Every PrintRegionConfig field is registered in a preset key list", "[Preset][Config]")
+{
+    check_keys_are_in_a_preset(PrintRegionConfig::defaults().keys(), "PrintRegionConfig");
+}
+
+TEST_CASE("Every PrintObjectConfig field is registered in a preset key list", "[Preset][Config]")
+{
+    check_keys_are_in_a_preset(PrintObjectConfig::defaults().keys(), "PrintObjectConfig");
+}
+// clang-format on