Fill Settings Missing From a CLI Project From Its System Presets

A project saved before a printer or process option existed has no value
for it. The GUI takes such keys from the project's system preset; the
CLI left them at the option default, so e.g. extruder_clearance_dist_to_rod
sliced as 40 instead of the P1S's 33.

The CLI now resolves the project's system printer and process presets by
name and copies the keys the project lacks, skipping preset bookkeeping,
print-host keys, the extruder variant layout and keys the legacy handler
drops. PresetBundle::resolve_system_preset finds the vendor through its
manifest or preset cache, so it also works in release builds, which ship
vendors as caches only.

src/OrcaSlicer.cpp

@@ -2116,7 +2116,12 @@ int CLI::run(int argc, char **argv)
 
     // One resolver for the whole run, so presets from the same vendor tree share its load.
     std::unique_ptr<PresetBundle> system_preset_resolver;
-    auto resolve_preset = [&ensure_cli_preset_bundle, &system_preset_resolver](const std::string &file, DynamicPrintConfig &config,
+    auto ensure_system_preset_resolver = [&system_preset_resolver]() -> PresetBundle & {
+        if (!system_preset_resolver)
+            system_preset_resolver = std::make_unique<PresetBundle>();
+        return *system_preset_resolver;
+    };
+    auto resolve_preset = [&ensure_cli_preset_bundle, &ensure_system_preset_resolver](const std::string &file, DynamicPrintConfig &config,
                                                                                       std::string &config_type, const std::string &config_from,
                                                                                       bool probe_type, std::string &error) {
         const auto *inherits = config.option<ConfigOptionString>(BBL_JSON_KEY_INHERITS);
@@ -2126,9 +2131,7 @@ int CLI::run(int argc, char **argv)
         PresetBundle                 *bundle = nullptr;
         bool                          allow_source_manifest = false;
         if (config_from == "system") {
-            if (!system_preset_resolver)
+            bundle                = &ensure_system_preset_resolver();
-                system_preset_resolver = std::make_unique<PresetBundle>();
-            bundle                = system_preset_resolver.get();
             allow_source_manifest = true;
         } else {
             bundle = ensure_cli_preset_bundle(error);
@@ -3120,6 +3123,49 @@ int CLI::run(int argc, char **argv)
         return 0;
     };
 
+    // A project saved before a printer or process option existed has no value for it. The GUI takes such
+    // keys from the project's system preset (load_external_preset refreshes every key the project did not
+    // override), so fill them from there too instead of leaving them to the option default.
+    // The extruder variant keys describe the project's variant layout and are kept as they are, so an
+    // older project is not left with a variant list from one layout and ids from another.
+    auto fill_missing_project_keys = [this, &ensure_system_preset_resolver](const std::string &system_name, Preset::Type type) {
+        if (system_name.empty())
+            return;
+        static const std::set<std::string> skip_keys = {
+            "inherits", "compatible_printers", "compatible_prints", "compatible_printers_condition", "compatible_prints_condition",
+            "print_settings_id", "filament_settings_id", "printer_settings_id",
+            "print_host", "print_host_webui", "printhost_apikey", "printhost_cafile", "printhost_user", "printhost_password", "printhost_port",
+            "printer_extruder_id", "printer_extruder_variant", "print_extruder_id", "print_extruder_variant", "extruder_variant_list"};
+        const std::vector<std::string> &options = type == Preset::TYPE_PRINTER ? Preset::printer_options() : Preset::print_options();
+        // Keys the legacy handler drops on load can never be in a project, so they do not count as missing.
+        auto dropped_on_load = [](std::string key) {
+            std::string value;
+            PrintConfigDef::handle_legacy(key, value);
+            return key.empty();
+        };
+        std::vector<std::string> missing;
+        for (const std::string &key : options)
+            if (m_print_config.option(key) == nullptr && skip_keys.count(key) == 0 && !dropped_on_load(key))
+                missing.push_back(key);
+        if (missing.empty())
+            return;
+        DynamicPrintConfig system_config;
+        std::string        error;
+        if (!ensure_system_preset_resolver().resolve_system_preset(system_config, type, system_name, config_substitution_rule, error)) {
+            BOOST_LOG_TRIVIAL(warning) << boost::format("CLI: system preset '%1%' not resolved (%2%); keys missing from the project keep their defaults") % system_name % error;
+            return;
+        }
+        for (const std::string &key : missing)
+            if (const ConfigOption *opt = system_config.option(key)) {
+                m_print_config.set_key_value(key, opt->clone());
+                BOOST_LOG_TRIVIAL(info) << boost::format("CLI: %1% missing from the project, taken from '%2%': %3%") % key % system_name % opt->serialize();
+            }
+    };
+    if (new_printer_name.empty())
+        fill_missing_project_keys(current_printer_system_name, Preset::TYPE_PRINTER);
+    if (new_process_name.empty())
+        fill_missing_project_keys(current_process_system_name, Preset::TYPE_PRINT);
+
     std::vector<std::string>& different_settings = m_print_config.option<ConfigOptionStrings>("different_settings_to_system", true)->values;
     std::vector<std::string>& inherits_group = m_print_config.option<ConfigOptionStrings>("inherits_group", true)->values;
     inherits_group.resize(filament_count + 2, std::string());

src/libslic3r/Format/bbs_3mf.cpp

@@ -1629,7 +1629,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         }
         while (it != m_plater_data.end())
         {
-            if (it->first <= 0 || static_cast<size_t>(it->first) > m_plater_data.size())
+            if (it->first > m_plater_data.size())
             {
                 add_error("invalid plate index");
                 return false;
@@ -2312,7 +2312,7 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         }
         while (it != m_plater_data.end())
         {
-            if (it->first <= 0 || static_cast<size_t>(it->first) > m_plater_data.size())
+            if (it->first > m_plater_data.size())
             {
                 add_error("invalid plate index");
                 return false;

src/libslic3r/GCode.cpp

@@ -2504,7 +2504,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(print->model().id().id);
+        ctx.id = std::to_string(print->model().id().id);
+        ctx.name = print->get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = path;
         ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2556,7 +2557,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
         }
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(print->model().id().id);
+            ctx.id = std::to_string(print->model().id().id);
+            ctx.name = print->get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = std::string(path) + "\n" + err_msg;
             ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2580,7 +2582,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
         boost::nowide::remove(path_tmp.c_str());
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(print->model().id().id);
+            ctx.id = std::to_string(print->model().id().id);
+            ctx.name = print->get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = std::string(path) + "\n" + ex.what();
             ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2693,7 +2696,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
     if (ret) {
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(print->model().id().id);
+            ctx.id = std::to_string(print->model().id().id);
+            ctx.name = print->get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = std::string(path) + "\nFailed to rename the output G-code file: " + ret.message();
             ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2712,7 +2716,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(print->model().id().id);
+        ctx.id = std::to_string(print->model().id().id);
+        ctx.name = print->get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = path;
         ctx.cancellation_check = [print]() { return print->canceled(); };

src/libslic3r/Model.cpp

@@ -3702,11 +3702,7 @@ void FacetsAnnotation::set_triangle_from_string(int triangle_id, const std::stri
             m_data.bitstream.insert(m_data.bitstream.end(), bool(dec & (1 << i)));
     }
 
-    if (!m_data.update_used_states(bitstream_start_idx)) {
+    m_data.update_used_states(bitstream_start_idx);
-        BOOST_LOG_TRIVIAL(warning) << __FUNCTION__ << ": dropping malformed paint data of triangle " << triangle_id;
-        m_data.bitstream.resize(bitstream_start_idx);
-        m_data.triangles_to_split.pop_back();
-    }
 }
 
 bool FacetsAnnotation::equals(const FacetsAnnotation &other) const

src/libslic3r/PresetBundle.cpp

@@ -575,18 +575,20 @@ bool PresetBundle::resolve_preset_config(DynamicPrintConfig &config, Preset::Typ
 const PresetBundle *PresetBundle::load_source_vendor(const boost::filesystem::path &root_dir,
                                                     const std::string &vendor_id,
                                                     ForwardCompatibilitySubstitutionRule compatibility_rule,
-                                                    std::string &error)
+                                                    std::string &error, bool allow_cache)
 {
-    auto key = std::make_tuple(root_dir.string(), vendor_id, compatibility_rule);
+    auto key = std::make_tuple(root_dir.string(), vendor_id, compatibility_rule, allow_cache);
     if (auto it = m_source_vendor_bundles.find(key); it != m_source_vendor_bundles.end())
         return it->second.get();
 
     // The library loads with no base of its own, so the tree a vendor inherits from
     // is the same one that resolves the library's own presets.
+    const std::string   library_file = std::string(ORCA_FILAMENT_LIBRARY);
     const PresetBundle *library      = nullptr;
     if (vendor_id != ORCA_FILAMENT_LIBRARY &&
-        boost::filesystem::is_regular_file(root_dir / (std::string(ORCA_FILAMENT_LIBRARY) + ".json"))) {
+        (boost::filesystem::is_regular_file(root_dir / (library_file + ".json")) ||
-        library = load_source_vendor(root_dir, ORCA_FILAMENT_LIBRARY, compatibility_rule, error);
+         (allow_cache && boost::filesystem::is_regular_file(root_dir / (library_file + ".opc"))))) {
+        library = load_source_vendor(root_dir, ORCA_FILAMENT_LIBRARY, compatibility_rule, error, allow_cache);
         if (library == nullptr) {
             error = "OrcaFilamentLibrary contains invalid presets";
             return nullptr;
@@ -595,7 +597,7 @@ const PresetBundle *PresetBundle::load_source_vendor(const boost::filesystem::pa
 
     auto bundle = std::make_unique<PresetBundle>();
     bundle->m_preserve_vendor_source_paths = true;
-    bundle->load_vendor_configs_from_json(root_dir.string(), vendor_id, LoadSystem, compatibility_rule, library, false);
+    bundle->load_vendor_configs_from_json(root_dir.string(), vendor_id, LoadSystem, compatibility_rule, library, allow_cache);
     if (bundle->error_count() != 0) {
         error = "Vendor bundle contains invalid presets";
         return nullptr;
@@ -638,6 +640,43 @@ bool PresetBundle::resolve_preset_config_type(DynamicPrintConfig &config, Preset
     return true;
 }
 
+bool PresetBundle::resolve_system_preset(DynamicPrintConfig &config, Preset::Type type, const std::string &name,
+                                         ForwardCompatibilitySubstitutionRule compatibility_rule, std::string &error)
+{
+    const std::string vendor_id = find_preset_vendor(name, type);
+    if (vendor_id.empty()) {
+        error = "No vendor lists the preset";
+        return false;
+    }
+    // Release builds ship a vendor as its preset cache alone, without the profile JSONs.
+    auto installed = [&vendor_id](const fs::path &root) {
+        return fs::is_regular_file(root / (vendor_id + ".json")) || fs::is_regular_file(root / (vendor_id + ".opc"));
+    };
+    fs::path root_dir = fs::path(data_dir()) / PRESET_SYSTEM_DIR;
+    if (!installed(root_dir))
+        root_dir = fs::path(resources_dir()) / PRESET_PROFILES_DIR;
+    const bool cache_only = !fs::is_regular_file(root_dir / (vendor_id + ".json"));
+
+    try {
+        const PresetBundle *vendor = load_source_vendor(root_dir, vendor_id, compatibility_rule, error, cache_only);
+        if (vendor == nullptr)
+            return false;
+        const PresetCollection &collection = type == Preset::TYPE_PRINTER ? vendor->printers :
+                                             type == Preset::TYPE_PRINT   ? vendor->prints : vendor->filaments;
+        const Preset *preset = collection.find_preset(name, false);
+        if (preset == nullptr) {
+            error = "Preset was not found in its vendor bundle";
+            return false;
+        }
+        config = preset->config;
+    } catch (const std::exception &ex) {
+        error = ex.what();
+        return false;
+    }
+    error.clear();
+    return true;
+}
+
 PresetBundle::PresetBundle(const PresetBundle &rhs)
 {
     *this = rhs;

src/libslic3r/PresetBundle.hpp

@@ -273,6 +273,10 @@ public:
                                     const std::string &source_file,
                                     ForwardCompatibilitySubstitutionRule compatibility_rule,
                                     std::string &error, bool allow_source_manifest = true);
+    // Resolve a system preset by name. The vendor tree is read from data_dir()/system when installed
+    // there, as the GUI reads it, and from the bundled profiles otherwise.
+    bool resolve_system_preset(DynamicPrintConfig &config, Preset::Type type, const std::string &name,
+                               ForwardCompatibilitySubstitutionRule compatibility_rule, std::string &error);
 
     // Load selections (current print, current filaments, current printer) from config.ini
     // This is done just once on application start up.
@@ -663,13 +667,14 @@ private:
     // Vendor trees loaded by resolve_preset_config's manifest path, so every preset
     // resolved through this bundle shares one load per source root and vendor. The
     // filament library is one such tree, shared by every vendor under its root.
-    std::map<std::tuple<std::string, std::string, ForwardCompatibilitySubstitutionRule>, std::unique_ptr<PresetBundle>>
+    // A tree read from its preset cache is kept apart: its presets carry no source file.
+    std::map<std::tuple<std::string, std::string, ForwardCompatibilitySubstitutionRule, bool>, std::unique_ptr<PresetBundle>>
         m_source_vendor_bundles;
 
     const PresetBundle *load_source_vendor(const boost::filesystem::path &root_dir,
                                            const std::string &vendor_id,
                                            ForwardCompatibilitySubstitutionRule compatibility_rule,
-                                           std::string &error);
+                                           std::string &error, bool allow_cache = false);
 
     // Orca: validation only - flag any printer with two or more compatible
     // filament presets sharing one filament_id (ambiguous AMS subtype match).

src/libslic3r/Print.cpp

@@ -2717,7 +2717,8 @@ void Print::process(long long *time_cost_with_cache, bool use_cache)
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.cancellation_check = [this]() { return canceled(); };
         fire_lifecycle_event(LifecycleEvent::SliceStarted, ctx);
@@ -3344,7 +3345,8 @@ void Print::process(long long *time_cost_with_cache, bool use_cache)
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.cancellation_check = [this]() { return canceled(); };
         fire_lifecycle_event(LifecycleEvent::SliceGeometryFinished, ctx);
@@ -4950,7 +4952,8 @@ void Print::export_gcode_from_previous_file(const std::string& file, GCodeProces
 {
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = file;
         ctx.cancellation_check = [this]() { return canceled(); };
@@ -4980,7 +4983,8 @@ void Print::export_gcode_from_previous_file(const std::string& file, GCodeProces
         BOOST_LOG_TRIVIAL(error) << __FUNCTION__ <<  boost::format(": found errors when process gcode file %1%") %file.c_str();
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(m_model.id().id);
+            ctx.id = std::to_string(m_model.id().id);
+            ctx.name = get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = file + "\n" + ex.what();
             ctx.cancellation_check = [this]() { return canceled(); };
@@ -4994,7 +4998,8 @@ void Print::export_gcode_from_previous_file(const std::string& file, GCodeProces
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = file;
         ctx.cancellation_check = [this]() { return canceled(); };

src/libslic3r/TriangleSelector.cpp

@@ -1778,13 +1778,6 @@ TriangleSelector::TriangleSplittingData TriangleSelector::serialize() const {
     return out.data;
 }
 
-// A split code keeps the split side (one split) or the kept side (two splits) in its upper two
-// bits, where 3 is not a side. The value is ignored for a three-side split.
-static bool split_code_valid(int code)
-{
-    return (code & 0b11) == 3 || (code >> 2) != 3;
-}
-
 void TriangleSelector::deserialize(const TriangleSplittingData &data,
                                    bool                         needs_reset,
                                    EnforcerBlockerType          max_ebt,
@@ -1819,12 +1812,11 @@ void TriangleSelector::deserialize(const TriangleSplittingData &data,
 
     for (auto [triangle_id, ibit] : data.triangles_to_split) {
         assert(triangle_id < int(m_triangles.size()));
-        // Set when the bitstream runs out or holds an impossible split before this triangle's tree is complete.
+        assert(ibit < int(data.bitstream.size()));
-        bool corrupt = false;
+        auto next_nibble = [&data, &ibit = ibit]() {
-        auto next_nibble = [&data, &ibit = ibit, &corrupt]() {
             int n = 0;
-            if (! data.read_nibble(ibit, n))
+            for (int i = 0; i < 4; ++ i)
-                corrupt = true;
+                n |= data.bitstream[ibit ++] << i;
             return n;
         };
         // Decode a leaf state stored behind the "11" prefix: one nibble of (state-3) for states
@@ -1843,10 +1835,6 @@ void TriangleSelector::deserialize(const TriangleSplittingData &data,
             bool is_split = num_of_children != 0;
             // Only valid if not is_split.
             auto state = is_split ? EnforcerBlockerType::NONE : ((code & 0b1100) == 0b1100 ? decode_leaf_state() : EnforcerBlockerType(code >> 2));
-            if (is_split && ! split_code_valid(code))
-                corrupt = true;
-            if (corrupt)
-                break;
 
             // BBS
             if (state == to_delete_filament)
@@ -1861,7 +1849,7 @@ void TriangleSelector::deserialize(const TriangleSplittingData &data,
             }
 
             // Only valid if is_split.
-            int special_side = num_of_split_sides == 3 ? 0 : code >> 2;
+            int special_side = code >> 2;
 
             // Take care of the first iteration separately, so handling of the others is simpler.
             if (parents.empty()) {
@@ -1916,55 +1904,47 @@ void TriangleSelector::deserialize(const TriangleSplittingData &data,
             if (parents.empty())
                 break;
         }
-
-        if (corrupt) {
-            // Every split above allocated all of its children, so the partial tree unwinds cleanly.
-            BOOST_LOG_TRIVIAL(warning) << __FUNCTION__ << ": malformed paint data, dropping paint of triangle " << triangle_id;
-            undivide_triangle(triangle_id);
-            m_triangles[triangle_id].set_state(EnforcerBlockerType::NONE);
-        }
     }
 }
 
-bool TriangleSelector::TriangleSplittingData::update_used_states(const size_t bitstream_start_idx) {
+void TriangleSelector::TriangleSplittingData::update_used_states(const size_t bitstream_start_idx) {
-    int      ibit   = static_cast<int>(bitstream_start_idx);
+    assert(bitstream_start_idx < this->bitstream.size());
-    uint64_t states = 0;
+    assert(!this->bitstream.empty() && this->bitstream.size() != bitstream_start_idx);
-    do {
+    assert((this->bitstream.size() - bitstream_start_idx) % 4 == 0);
-        // Walk one triangle's tree depth-first, counting the nodes still to be read; a split node adds its children.
-        for (int pending_nodes = 1; pending_nodes > 0; --pending_nodes) {
-            int code;
-            if (!this->read_nibble(ibit, code))
-                return false;
 
-            if (const int num_of_split_sides = code & 0b11; num_of_split_sides != 0) {
+    if (this->bitstream.empty() || this->bitstream.size() == bitstream_start_idx)
-                if (!split_code_valid(code))
+        return;
-                    return false;
+
-                pending_nodes += num_of_split_sides + 1;
+    size_t nibble_idx = bitstream_start_idx;
+
+    auto read_next_nibble = [&data_bitstream = std::as_const(this->bitstream), &nibble_idx]() -> uint8_t {
+        assert(nibble_idx + 3 < data_bitstream.size());
+        uint8_t code = 0;
+        for (size_t bit_idx = 0; bit_idx < 4; ++bit_idx)
+            code |= data_bitstream[nibble_idx++] << bit_idx;
+        return code;
+    };
+
+    while (nibble_idx < this->bitstream.size()) {
+        const uint8_t code = read_next_nibble();
+
+        if (const bool is_split = (code & 0b11) != 0; is_split)
             continue;
-            }
 
-            int facet_state = code >> 2;
+        uint8_t facet_state;
-            if (facet_state == 0b11) {
+        if ((code & 0b1100) == 0b1100) {
             // Leaf behind the "11" prefix: one nibble of (state-3), or 0b1111 + (state-18).
-                int nibble;
+            const uint8_t nibble = read_next_nibble();
-                if (!this->read_nibble(ibit, nibble))
+            facet_state = nibble == 0b1111 ? uint8_t(read_next_nibble() + 18) : uint8_t(nibble + 3);
-                    return false;
+        } else {
-                facet_state = nibble + 3;
+            facet_state = code >> 2;
-                if (nibble == 0b1111) {
-                    if (!this->read_nibble(ibit, nibble))
-                        return false;
-                    facet_state = nibble + 18;
         }
-            }
+        assert(facet_state < this->used_states.size());
-            states |= uint64_t(1) << facet_state;
+        if (facet_state >= this->used_states.size())
-        }
+            continue;
-    } while (static_cast<size_t>(ibit) < this->bitstream.size());
 
-    // The leaf encoding tops out at state 33, so every state fits the 64-bit mask.
+        this->used_states[facet_state] = true;
-    for (size_t state_idx = 0; state_idx < std::min<size_t>(this->used_states.size(), 64); ++state_idx)
+    }
-        if (states & (uint64_t(1) << state_idx))
-            this->used_states[state_idx] = true;
-    return true;
 }
 
 // Lightweight variant of deserialization, which only tests whether a face of test_state exists.
@@ -1976,12 +1956,11 @@ bool TriangleSelector::has_facets(const TriangleSplittingData &data, const Enfor
 
     for (const TriangleBitStreamMapping &triangle_id_and_ibit : data.triangles_to_split) {
         int ibit = triangle_id_and_ibit.bitstream_start_idx;
-        // Stop reading a triangle whose stream is truncated.
+        assert(ibit < int(data.bitstream.size()));
-        bool truncated = false;
+        auto next_nibble = [&data, &ibit = ibit]() {
-        auto next_nibble = [&data, &ibit = ibit, &truncated]() {
             int n = 0;
-            if (! data.read_nibble(ibit, n))
+            for (int i = 0; i < 4; ++ i)
-                truncated = true;
+                n |= data.bitstream[ibit ++] << i;
             return n;
         };
         // < 0 -> negative of a number of children
@@ -1999,8 +1978,6 @@ bool TriangleSelector::has_facets(const TriangleSplittingData &data, const Enfor
         };
 
         int state = num_children_or_state();
-        if (truncated)
-            continue;
         if (state < 0) {
             // Root is split.
             parents_children.clear();
@@ -2008,8 +1985,6 @@ bool TriangleSelector::has_facets(const TriangleSplittingData &data, const Enfor
             do {
                 if (-- parents_children.back() >= 0) {
                     int state = num_children_or_state();
-                    if (truncated)
-                        break;
                     if (state < 0)
                         // Child is split.
                         parents_children.emplace_back(- state);

src/libslic3r/TriangleSelector.hpp

@@ -297,20 +297,8 @@ public:
             std::fill(used_states.begin(), used_states.end(), false);
         }
 
-        // Update used states from the triangle trees stored between bitstream_start_idx and the end of the bitstream.
+        // Update used states based on the bitstream. It just iterated over the bitstream from the bitstream_start_idx till the end.
-        // Returns false and leaves used states untouched if a tree is truncated or malformed.
+        void update_used_states(size_t bitstream_start_idx);
-        bool update_used_states(size_t bitstream_start_idx);
-
-        // Read the 4-bit code at bit index ibit (LSB first) and advance ibit past it.
-        // Returns false without advancing when fewer than 4 bits remain.
-        bool read_nibble(int &ibit, int &nibble) const {
-            if (ibit < 0 || static_cast<size_t>(ibit) + 4 > bitstream.size())
-                return false;
-            nibble = 0;
-            for (int i = 0; i < 4; ++i)
-                nibble |= static_cast<int>(bitstream[ibit++]) << i;
-            return true;
-        }
 
     private:
         friend class cereal::access;

src/libvgcode/src/Shaders.hpp

@@ -34,6 +34,10 @@ static const char* Segments_Vertex_Shader =
 // ORCA: 0 during the shadow caster pass - the bias below shifts eye_position but not
 // world_position, so the caster would write a depth the receiver never looks up.
 "uniform float bias_scale;\n"
+// draw the instances last to first, top layers before the ones they hide, so that early depth
+// rejection discards most of the hidden fragments; set when the camera looks down on the print
+"uniform int reverse_order;\n"
+"uniform int instance_count;\n"
 "in int vertex_id;\n"
 "out vec3 color;\n"
 "// ORCA: realistic view - the light the shadow map is able to block, kept apart from the\n"
@@ -59,7 +63,8 @@ static const char* Segments_Vertex_Shader =
 "  return top_diffuse + front_diffuse + top_specular;\n"
 "}\n"
 "void main() {\n"
-"  int id_a = int(texelFetch(segment_index_tex, gl_InstanceID).r);\n"
+"  int instance = (reverse_order != 0) ? instance_count - 1 - gl_InstanceID : gl_InstanceID;\n"
+"  int id_a = int(texelFetch(segment_index_tex, instance).r);\n"
 "  int id_b = id_a + 1;\n"
 "  vec3 pos_a = texelFetch(position_tex, id_a).xyz;\n"
 "  vec3 pos_b = texelFetch(position_tex, id_b).xyz;\n"

src/libvgcode/src/ViewerImpl.cpp

@@ -763,6 +763,8 @@ void ViewerImpl::init(const std::string& opengl_context_version)
     m_uni_segments_height_width_angle_tex_id = glGetUniformLocation(m_segments_shader_id, "height_width_angle_tex");
     m_uni_segments_colors_tex_id             = glGetUniformLocation(m_segments_shader_id, "color_tex");
     m_uni_segments_segment_index_tex_id      = glGetUniformLocation(m_segments_shader_id, "segment_index_tex");
+    m_uni_segments_reverse_order_id          = glGetUniformLocation(m_segments_shader_id, "reverse_order");
+    m_uni_segments_instance_count_id         = glGetUniformLocation(m_segments_shader_id, "instance_count");
     // ORCA: realistic view
     m_uni_segments_shadow_map_id             = glGetUniformLocation(m_segments_shader_id, "shadow_map");
     m_uni_segments_shadow_light_vp_id        = glGetUniformLocation(m_segments_shader_id, "shadow_light_vp");
@@ -2090,6 +2092,15 @@ void ViewerImpl::render_segments(const Mat4x4& view_matrix, const Mat4x4& projec
     glsafe(glUniformMatrix4fv(m_uni_segments_view_matrix_id, 1, GL_FALSE, view_matrix.data()));
     glsafe(glUniformMatrix4fv(m_uni_segments_projection_matrix_id, 1, GL_FALSE, projection_matrix.data()));
     glsafe(glUniform3fv(m_uni_segments_camera_position_id, 1, camera_position.data()));
+    // The segments come in print order, bottom layer first. Seen from above, that is back to front,
+    // and every hidden fragment is shaded before the one that covers it. Drawing them last to first
+    // lets the depth test reject the hidden ones instead. The camera looks down when the world's
+    // up axis points towards it, which is the view matrix's (2, 2) entry being positive.
+    const bool top_down = !m_rendering_shadow_casters && view_matrix[10] > 0.0f;
+    glsafe(glUniform1i(m_uni_segments_reverse_order_id, top_down ? 1 : 0));
+#ifndef ENABLE_OPENGL_ES
+    glsafe(glUniform1i(m_uni_segments_instance_count_id, static_cast<int>(m_enabled_segments_count)));
+#endif // ENABLE_OPENGL_ES
     // ORCA: realistic view. The depth pass writes the map it would otherwise read, so it shades
     // with the lookup off.
     glsafe(glUniform1i(m_uni_segments_shadow_map_id, m_shadow_map_texture_unit));

src/libvgcode/src/ViewerImpl.hpp

@@ -362,6 +362,8 @@ private:
     int m_uni_segments_height_width_angle_tex_id{ -1 };
     int m_uni_segments_colors_tex_id{ -1 };
     int m_uni_segments_segment_index_tex_id{ -1 };
+    int m_uni_segments_reverse_order_id{ -1 };
+    int m_uni_segments_instance_count_id{ -1 };
     int m_uni_segments_shadow_map_id{ -1 };
     int m_uni_segments_shadow_light_vp_id{ -1 };
     int m_uni_segments_shadow_intensity_id{ -1 };

src/slic3r/GUI/Plater.cpp

@@ -12800,8 +12800,6 @@ void Plater::priv::on_process_completed(SlicingProcessCompletedEvent &evt)
     notification_manager->set_slicing_progress_export_possible();
 
     // Reset the "export G-code path" name, so that the automatic background processing will be enabled again.
-    const std::string lifecycle_job_name = this->background_process.fff_print() ?
-        this->background_process.fff_print()->output_filename() : std::string();
     this->background_process.reset_export();
     // This bool stops showing export finished notification even when process_completed_with_error is false
     bool has_error = false;
@@ -12848,8 +12846,18 @@ void Plater::priv::on_process_completed(SlicingProcessCompletedEvent &evt)
 
     {
         Slic3r::LifecycleEventContext ctx;
-        ctx.name = lifecycle_job_name;
+        if (const PrintBase* print = this->background_process.current_print()) {
-        ctx.code = evt.cancelled() ? Slic3r::LifecycleEvtCode::Warn : (has_error ? Slic3r::LifecycleEvtCode::Error : Slic3r::LifecycleEvtCode::Ok);
+            const Model& model = print->model();
+            ctx.id             = std::to_string(model.id().id);
+            if (model.model_info)
+                ctx.name = model.model_info->model_name;
+        } else {
+            // Realistically Printbase* print will never be null because select_technology already asserts an active print
+            // and the worker thread asserts it before processing.
+            BOOST_LOG_TRIVIAL(warning) << __FUNCTION__ << ": slicing completed without an active print; lifecycle event has no model ID";
+        }
+        ctx.code = evt.cancelled() ? Slic3r::LifecycleEvtCode::Warn :
+                                     (has_error ? Slic3r::LifecycleEvtCode::Error : Slic3r::LifecycleEvtCode::Ok);
         ctx.msg  = evt.cancelled() ? "cancelled" : (has_error ? lifecycle_error_msg : std::string());
         Slic3r::fire_lifecycle_event(Slic3r::LifecycleEvent::SlicingJobComplete, ctx);
     }

src/slic3r/Utils/PrintHost.cpp

@@ -6,6 +6,7 @@
 #include <boost/optional.hpp>
 #include <boost/log/trivial.hpp>
 #include <boost/filesystem.hpp>
+#include <nlohmann/json.hpp>
 
 #include <wx/string.h>
 #include <wx/app.h>
@@ -115,10 +116,67 @@ std::string PrintHost::get_print_host_webui(DynamicPrintConfig* config)
     return webui_url;
 }
 
+namespace {
+
+// Moonraker (Klipper's API server) reports a raised exception as { "error": { "code", "message", "traceback" } }
+// under every host type that connects to it, often with the cause only in the traceback. Returns the reason to show,
+// or empty for any other body.
+std::string moonraker_error_reason(const std::string &body)
+{
+    const auto root = nlohmann::json::parse(body, nullptr, false);
+    const auto err  = root.find("error");
+    if (err == root.end())
+        return {};
+    const auto message   = err->find("message");
+    const auto traceback = err->find("traceback");
+    if (message == err->end() || traceback == err->end() || !message->is_string() || !traceback->is_string())
+        return {};
+
+    const auto &msg = message->get_ref<const std::string &>();
+    const auto &tb  = traceback->get_ref<const std::string &>();
+    if (msg.empty())
+        return {};
+    const auto end = tb.find_last_not_of(" \t\r\n");
+    if (end == std::string::npos)
+        return msg;
+
+    // Chained exceptions each start a new traceback; the one that failed the request is the last.
+    const auto header = tb.rfind("Traceback (most recent call last):", end);
+
+    // Tornado renders a raised HTTPError as "HTTP <code>: <reason>[ (<detail>)]", and the detail may span lines.
+    const auto code = err->find("code");
+    if (code != err->end() && code->is_number_integer()) {
+        const std::string marker = "HTTP " + std::to_string(code->get<int>()) + ": ";
+        const auto        pos    = tb.rfind(marker, end);
+        if (pos != std::string::npos && (header == std::string::npos || pos > header) && pos + marker.size() <= end) {
+            const std::string reason = tb.substr(pos + marker.size(), end + 1 - pos - marker.size());
+            // An HTTPError whose detail equals its reason, like HTTPError(401, "Unauthorized"), renders the phrase twice.
+            return reason == msg + " (" + msg + ")" ? msg : reason;
+        }
+    }
+
+    // Any other exception's type and message are everything from the first unindented line after its frames.
+    auto begin = (header == std::string::npos) ? std::string::npos : tb.find('\n', header);
+    while (begin != std::string::npos && begin < end) {
+        ++begin;
+        if (tb[begin] != ' ' && tb[begin] != '\r' && tb[begin] != '\n')
+            break;
+        begin = tb.find('\n', begin);
+    }
+    if (begin == std::string::npos || begin > end) {
+        const auto nl = tb.rfind('\n', end);
+        begin         = (nl == std::string::npos) ? 0 : nl + 1;
+    }
+    return msg + " (" + tb.substr(begin, end + 1 - begin) + ")";
+}
+
+} // namespace
+
 wxString PrintHost::format_error(const std::string &body, const std::string &error, unsigned status) const
 {
     if (status != 0) {
-        auto wxbody = wxString::FromUTF8(body.data());
+        const std::string reason = moonraker_error_reason(body);
+        auto wxbody = wxString::FromUTF8(reason.empty() ? body : reason);
         return wxString::Format("HTTP %u: %s", status, wxbody);
     } else {
         if (error.find("curl:Timeout was reached") != std::string::npos) {

tests/cli/CMakeLists.txt

@@ -15,3 +15,11 @@ set_tests_properties(cli_strict_mode PROPERTIES
     LABELS "CLI;RequiresApp"
     SKIP_RETURN_CODE 77
     TIMEOUT 900)
+
+add_test(NAME cli_project_missing_keys
+    COMMAND bash ${CMAKE_CURRENT_SOURCE_DIR}/test_cli_project_missing_keys.sh $<TARGET_FILE:OrcaSlicer> ${ORCA_CLI_TEST_PYTHON}
+        ${CMAKE_SOURCE_DIR}/resources/profiles/BBL)
+set_tests_properties(cli_project_missing_keys PROPERTIES
+    LABELS "CLI;RequiresApp"
+    SKIP_RETURN_CODE 77
+    TIMEOUT 900)

tests/cli/test_cli_project_missing_keys.sh

@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+# End-to-end check that the CLI fills settings missing from a project from the project's system presets.
+#
+# A project saved before an option existed has no value for it. The GUI takes such keys from the
+# project's system printer and process presets, not from the option defaults, and the CLI must slice
+# the project with the same values. A project is exported from the shipped Bambu Lab P1S presets, one
+# printer key and one process key are removed from it, one kept key is changed, and it is sliced again.
+#
+# usage: test_cli_project_missing_keys.sh <orca-slicer binary> <python3> <resources/profiles/BBL>
+set -u
+
+BIN="${1:-}"
+PY="${2:-python3}"
+PROFILES="${3:-}"
+# 77 is the test's SKIP_RETURN_CODE.
+[ -x "$BIN" ] || { echo "SKIP: orca-slicer binary not found: $BIN"; exit 77; }
+[ -d "$PROFILES" ] || { echo "FAIL: profiles directory not found: $PROFILES"; exit 1; }
+
+WORK="$(mktemp -d "${TMPDIR:-/tmp}/orca-cli-missing-keys.XXXXXX")"
+trap 'rm -rf "$WORK"' EXIT
+
+"$PY" - "$WORK/cube.stl" <<'EOF'
+import sys
+
+v = [(x, y, z) for z in (0, 10) for y in (0, 10) for x in (0, 10)]
+with open(sys.argv[1], "w") as f:
+    f.write("solid cube\n")
+    for a, b, c, d in ((0, 2, 3, 1), (4, 5, 7, 6), (0, 1, 5, 4), (2, 6, 7, 3), (0, 4, 6, 2), (1, 3, 7, 5)):
+        for tri in ((v[a], v[b], v[c]), (v[a], v[c], v[d])):
+            f.write("facet normal 0 0 0\nouter loop\n")
+            for p in tri:
+                f.write("vertex %g %g %g\n" % p)
+            f.write("endloop\nendfacet\n")
+    f.write("endsolid cube\n")
+EOF
+
+# slice <tag> <input> [option...]: slice into $WORK/<tag>/out.3mf with a fresh data directory.
+slice() {
+    local out="$WORK/$1" input="$2"; shift 2
+    mkdir -p "$out"
+    timeout 300 "$BIN" --datadir "$out/datadir" "$@" --slice 0 --outputdir "$out" --export-3mf out.3mf "$input" \
+        > "$out/log" 2>&1 || { echo "FAIL: $1: orca-slicer exited $?"; tail -n 40 "$out/log"; exit 1; }
+}
+
+slice base "$WORK/cube.stl" \
+    --load-settings "$PROFILES/machine/Bambu Lab P1S 0.4 nozzle.json;$PROFILES/process/0.20mm Standard @BBL X1C.json" \
+    --load-filaments "$PROFILES/filament/Bambu PLA Basic @BBL P1S 0.4 nozzle.json"
+
+# The removed keys, with their option defaults from PrintConfig.cpp, and a kept key with a new value.
+"$PY" - "$WORK/base/out.3mf" "$WORK/old.3mf" <<'EOF' || exit $?
+import json, sys, zipfile
+
+src, dst = sys.argv[1], sys.argv[2]
+missing = {"extruder_clearance_dist_to_rod": "40", "sparse_infill_density": "20%"}
+with zipfile.ZipFile(src) as zin, zipfile.ZipFile(dst, "w", zipfile.ZIP_DEFLATED) as zout:
+    for item in zin.infolist():
+        data = zin.read(item.filename)
+        if item.filename == "Metadata/project_settings.config":
+            config = json.loads(data)
+            for key, default in missing.items():
+                if config[key] == default:
+                    print("SKIP: %s is %s in the system preset, the option default, so the test cannot tell them apart" % (key, default))
+                    sys.exit(77)
+            expected = {key: config.pop(key) for key in missing}
+            expected["wall_loops"] = str(int(config["wall_loops"]) + 1)
+            config["wall_loops"] = expected["wall_loops"]
+            data = json.dumps(config, indent=4)
+        zout.writestr(item, data)
+with open(dst + ".expected.json", "w") as f:
+    json.dump(expected, f)
+EOF
+
+slice project "$WORK/old.3mf"
+
+"$PY" - "$WORK/project/out.3mf" "$WORK/old.3mf.expected.json" <<'EOF'
+import json, sys, zipfile
+
+with zipfile.ZipFile(sys.argv[1]) as z:
+    config = json.loads(z.read("Metadata/project_settings.config"))
+with open(sys.argv[2]) as f:
+    expected = json.load(f)
+errors = ["%s is %r, want %r" % (key, config.get(key), want) for key, want in expected.items() if config.get(key) != want]
+for e in errors:
+    print("FAIL: " + e)
+sys.exit(1 if errors else 0)
+EOF
+status=$?
+[ "$status" -eq 0 ] || { tail -n 40 "$WORK/project/log"; exit 1; }
+echo "PASS"

tests/fff_print/test_print.cpp

@@ -15,6 +15,9 @@
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/Model.hpp"
 #include "libslic3r/GCodeReader.hpp"
+#include "libslic3r/GCode/GCodeProcessor.hpp"
+#include "libslic3r/Exception.hpp"
+#include "libslic3r/LifecycleEvents.hpp"
 
 #include "test_helpers.hpp"
 #include "test_utils.hpp"
@@ -22,7 +25,10 @@
 #include <algorithm>
 #include <fstream>
 #include <iterator>
+#include <memory>
 #include <string_view>
+#include <utility>
+#include <vector>
 
 using namespace Slic3r;
 using namespace Slic3r::Test;
@@ -224,8 +230,88 @@ std::string resolved_output_name(Model& model, const std::string& format, const
     return print.output_filename(filename_base);
 }
 
+struct ScopedLifecycleHook
+{
+    explicit ScopedLifecycleHook(LifecycleHookFn hook) { set_lifecycle_hook_fn(std::move(hook)); }
+    ~ScopedLifecycleHook() { set_lifecycle_hook_fn(nullptr); }
+};
+
 } // namespace
 
+TEST_CASE("Slicing lifecycle events identify the model", "[Print][LifecycleEvents]")
+{
+    struct ObservedEvent {
+        LifecycleEvent event;
+        std::string id;
+        std::string name;
+    };
+    std::vector<ObservedEvent> events;
+    ScopedLifecycleHook hook([&](LifecycleEvent event, const LifecycleEventContext& ctx) {
+        events.push_back({ event, ctx.id, ctx.name });
+    });
+
+    Print print;
+    Model model;
+    ModelInfo info;
+    info.model_name = "Lifecycle test model";
+    model.model_info = std::make_shared<ModelInfo>(std::move(info));
+    init_print({cube(20)}, print, model);
+
+    print.process();
+    ScopedTemporaryFile temp(".gcode");
+    print.export_gcode(temp.string(), nullptr, nullptr);
+    GCodeProcessorResult result;
+    print.export_gcode_from_previous_file(temp.string(), &result);
+
+    const std::string expected_id = std::to_string(print.model().id().id);
+    const std::vector<LifecycleEvent> expected_events = {
+        LifecycleEvent::SliceStarted,
+        LifecycleEvent::SliceGeometryFinished,
+        LifecycleEvent::GCodeExportStarted,
+        LifecycleEvent::GCodeExportFinished,
+        LifecycleEvent::GCodeExportStarted,
+        LifecycleEvent::GCodeExportFinished,
+    };
+    REQUIRE(events.size() == expected_events.size());
+    for (size_t i = 0; i < expected_events.size(); ++i) {
+        CHECK(events[i].event == expected_events[i]);
+        CHECK(events[i].id == expected_id);
+        CHECK(events[i].name == "Lifecycle test model");
+    }
+}
+
+TEST_CASE("Slicing lifecycle event name is empty without model metadata", "[Print][LifecycleEvents]")
+{
+    std::string event_id;
+    std::string event_name = "unset";
+    ScopedLifecycleHook hook([&](LifecycleEvent event, const LifecycleEventContext& ctx) {
+        if (event == LifecycleEvent::SliceStarted) {
+            event_id = ctx.id;
+            event_name = ctx.name;
+        }
+    });
+
+    Print print;
+    Model model;
+    init_print({cube(20)}, print, model);
+    print.process();
+
+    CHECK(event_id == std::to_string(print.model().id().id));
+    CHECK(event_name.empty());
+}
+
+TEST_CASE("Output filenames with numeric statistics fail before slicing finishes", "[Print][Regression]")
+{
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+    config.set_key_value("filename_format", new ConfigOptionString("{int(total_weight*10) / 10.0}"));
+
+    Print print;
+    Model model;
+    init_print({cube(20)}, print, model, config);
+
+    CHECK_THROWS_AS(print.output_filename(), PlaceholderParserError);
+}
+
 TEST_CASE("Print: {first_object_name} names the first printable object on the plate", "[Print]")
 {
     Model model;

tests/libslic3r/test_3mf.cpp

@@ -19,7 +19,6 @@
 #include <boost/filesystem/operations.hpp>
 #include <boost/algorithm/string/predicate.hpp>
 #include <algorithm>
-#include <functional>
 
 #include <catch2/catch_tostring.hpp>
 #include <Eigen/Core>
@@ -185,13 +184,16 @@ static bool read_cad_recipe_entry(const std::string& path, std::string& out,
     return found;
 }
 
-// Rewrites the archive at `path`, letting `edit` change the name or data of each entry; returns
+// Rewrites the archive at `path` with the recipe entry back under the name it had before the
-// whether `edit` reported a change for any of them. miniz cannot edit in place and
+// rename, which is what every project saved by an earlier build looks like on disk. Generated
-// open_zip_writer truncates, so the entries are held across the switch.
+// rather than checked in because a whole project archive is not frozen evidence the way a bare
-static bool rewrite_3mf_entries(const std::string& path, const std::function<bool(std::string& name, std::string& data)>& edit)
+// recipe blob is -- it has to be whatever today's exporter writes, with only the name aged.
+// miniz cannot rename in place and open_zip_writer truncates, so the entries are held across
+// the switch.
+static void rename_cad_recipe_entry_to_legacy(const std::string& path)
 {
     std::vector<std::pair<std::string, std::string>> entries;
-    bool changed = false;
+    bool renamed = false;
     {
         mz_zip_archive zip;
         mz_zip_zero_struct(&zip);
@@ -206,140 +208,22 @@ static bool rewrite_3mf_entries(const std::string& path, const std::function<boo
             std::string data((size_t) st.m_uncomp_size, '\0');
             if (st.m_uncomp_size > 0)
                 REQUIRE(mz_zip_reader_extract_to_mem(&zip, i, data.data(), data.size(), 0));
-            changed |= edit(name, data);
+            if (boost::algorithm::iequals(name, CAD_RECIPE_ENTRY)) {
+                name    = LEGACY_CAD_RECIPE_ENTRY;
+                renamed = true;
+            }
             entries.emplace_back(std::move(name), std::move(data));
         }
         close_zip_reader(&zip);
     }
+    // Without this the scenario would degrade silently into re-testing the new name if the
+    // exporter's constant ever moved again: every load below would still pass.
+    REQUIRE(renamed);
 
     Zipper out(path);
     for (const auto& e : entries)
         out.add_entry(e.first, e.second.data(), e.second.size());
     out.finalize();
-    return changed;
-}
-
-// Rewrites the archive at `path` with the recipe entry back under the name it had before the
-// rename, which is what every project saved by an earlier build looks like on disk. Generated
-// rather than checked in because a whole project archive is not frozen evidence the way a bare
-// recipe blob is -- it has to be whatever today's exporter writes, with only the name aged.
-static void rename_cad_recipe_entry_to_legacy(const std::string& path)
-{
-    const bool renamed = rewrite_3mf_entries(path, [](std::string& name, std::string&) {
-        if (!boost::algorithm::iequals(name, CAD_RECIPE_ENTRY))
-            return false;
-        name = LEGACY_CAD_RECIPE_ENTRY;
-        return true;
-    });
-    // Without this the scenario would degrade silently into re-testing the new name if the
-    // exporter's constant ever moved again: every load below would still pass.
-    REQUIRE(renamed);
-}
-
-// Replaces the first occurrence of `from` in any entry whose name ends with `suffix`.
-static bool replace_in_3mf_entry(const std::string& path, const std::string& suffix, const std::string& from, const std::string& to)
-{
-    bool replaced = false;
-    rewrite_3mf_entries(path, [&](std::string& name, std::string& data) {
-        if (replaced || !boost::algorithm::ends_with(name, suffix))
-            return false;
-        if (const size_t pos = data.find(from); pos != std::string::npos) {
-            data.replace(pos, from.size(), to);
-            replaced = true;
-        }
-        return replaced;
-    });
-    return replaced;
-}
-
-// Stores a one-plate project holding a cube whose first two facets are painted Extruder2 and
-// Extruder3, which the exporter writes as paint_color="8" and paint_color="0C".
-static void store_painted_cube(const std::string& path)
-{
-    Model        model;
-    ModelObject* object = model.add_object();
-    ModelVolume* volume = object->add_volume(make_cube(10., 10., 10.));
-    object->add_instance();
-    {
-        TriangleSelector selector(volume->mesh());
-        selector.set_facet(0, EnforcerBlockerType::Extruder2);
-        selector.set_facet(1, EnforcerBlockerType::Extruder3);
-        REQUIRE(volume->mmu_segmentation_facets.set(selector));
-    }
-    ScopedTemporaryDir backup_dir("orca_paint_src");
-    model.set_backup_path(backup_dir.string());
-
-    DynamicPrintConfig cfg;
-    PlateData          plate;
-    plate.plate_index = 0;
-    StoreParams sp;
-    sp.path     = path.c_str();
-    sp.model    = &model;
-    sp.config   = &cfg;
-    sp.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
-    sp.plate_data_list.push_back(&plate);
-    REQUIRE(store_bbs_3mf(sp));
-}
-
-// Loads `path` through the BBS importer into `model`, releasing the plates it returns. The
-// importer stages metadata through `backup_dir`, which has to outlive the model.
-static bool load_project(const std::string& path, Model& model, const ScopedTemporaryDir& backup_dir)
-{
-    model.set_backup_path(backup_dir.string());
-    DynamicPrintConfig        config;
-    ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
-    PlateDataPtrs             plates;
-    std::vector<Preset*>      project_presets;
-    bool   is_bbl_3mf = false, is_orca_3mf = false;
-    Semver file_version;
-    const bool loaded = load_bbs_3mf(path.c_str(), &config, &ctxt, &model, &plates, &project_presets, &is_bbl_3mf,
-                                     &is_orca_3mf, &file_version, nullptr, LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
-    release_PlateData_list(plates);
-    return loaded;
-}
-
-TEST_CASE("A project with a plate id below 1 fails to load", "[3mf][Regression]")
-{
-    const int plate_id = GENERATE(0, -1);
-    INFO("plater_id " << plate_id);
-
-    ScopedTemporaryFile temp(".3mf");
-    store_painted_cube(temp.string());
-    {
-        ScopedTemporaryDir backup_dir("orca_plate_dst");
-        Model              model;
-        REQUIRE(load_project(temp.string(), model, backup_dir));
-    }
-
-    REQUIRE(replace_in_3mf_entry(temp.string(), "model_settings.config", "key=\"plater_id\" value=\"1\"",
-                                 "key=\"plater_id\" value=\"" + std::to_string(plate_id) + "\""));
-    ScopedTemporaryDir backup_dir("orca_plate_dst");
-    Model              model;
-    bool               loaded = true;
-    REQUIRE_NOTHROW(loaded = load_project(temp.string(), model, backup_dir));
-    REQUIRE_FALSE(loaded);
-}
-
-TEST_CASE("A project with malformed paint data loads without the damaged facet", "[3mf][Regression]")
-{
-    ScopedTemporaryFile temp(".3mf");
-    store_painted_cube(temp.string());
-    // Split codes with no children behind them: the stream runs out mid-tree.
-    REQUIRE(replace_in_3mf_entry(temp.string(), ".model", "paint_color=\"8\"", "paint_color=\"FFFFFFFFFFFFFFFF3\""));
-
-    ScopedTemporaryDir backup_dir("orca_paint_dst");
-    Model              model;
-    REQUIRE(load_project(temp.string(), model, backup_dir));
-    REQUIRE(model.objects.size() == 1);
-    const ModelVolume& volume = *model.objects.front()->volumes.front();
-    const auto&        data   = volume.mmu_segmentation_facets.get_data();
-    REQUIRE_FALSE(data.used_states[size_t(EnforcerBlockerType::Extruder2)]);
-    REQUIRE(data.used_states[size_t(EnforcerBlockerType::Extruder3)]);
-
-    TriangleSelector selector(volume.mesh());
-    REQUIRE_NOTHROW(selector.deserialize(data));
-    REQUIRE(selector.num_facets(EnforcerBlockerType::Extruder2) == 0);
-    REQUIRE(selector.num_facets(EnforcerBlockerType::Extruder3) == 1);
 }
 
 // The recipe lives only in the BBS-native backend, because that is the only one that runs:

tests/libslic3r/test_preset_bundle_loading.cpp

@@ -5405,6 +5405,35 @@ struct ScopedDataDir
     ~ScopedDataDir() { set_data_dir(previous); }
 };
 
+// resources_dir() is process-wide too; system preset lookups scan its profiles directory.
+struct ScopedResourcesDir
+{
+    std::string previous = resources_dir();
+    explicit ScopedResourcesDir(const fs::path &dir) { set_resources_dir(dir.string()); }
+    ~ScopedResourcesDir() { set_resources_dir(previous); }
+};
+
+// An "Acme" vendor under root whose "Acme Printer" inherits extruder_clearance_dist_to_rod from an
+// abstract base, with the printer in a nested sub_path so the name cannot be derived from the file.
+void write_acme_printer_vendor(const fs::path &root, double dist_to_rod)
+{
+    const fs::path machine_dir = root / "Acme" / "machine";
+    fs::create_directories(machine_dir / "nested");
+    std::ofstream((root / "Acme.json").string())
+        << R"({"version":"1.0.0","name":"Acme",)"
+        << R"("machine_model_list":[{"name":"Acme One","sub_path":"machine/model.json"}],"machine_list":[)"
+        << R"({"name":"fdm_acme_common","sub_path":"machine/base.json"},)"
+        << R"({"name":"Acme Printer","sub_path":"machine/nested/printer.json"}]})";
+    std::ofstream((machine_dir / "model.json").string())
+        << R"({"type":"machine_model","name":"Acme One","nozzle_diameter":"0.4"})";
+    std::ofstream((machine_dir / "base.json").string())
+        << R"({"type":"machine","name":"fdm_acme_common","from":"system","instantiation":"false",)"
+        << R"("extruder_clearance_dist_to_rod":")" << dist_to_rod << R"("})";
+    std::ofstream((machine_dir / "nested" / "printer.json").string())
+        << R"({"type":"machine","name":"Acme Printer","from":"system","instantiation":"true","inherits":"fdm_acme_common",)"
+        << R"("printer_model":"Acme One","printer_variant":"0.4"})";
+}
+
 std::string read_file(const fs::path &file)
 {
     std::ifstream in(file.string(), std::ios::binary);
@@ -5482,3 +5511,75 @@ TEST_CASE("Config import confines zip entries, preset names and bundle ids to th
         CHECK_FALSE(any_filename_contains(temp_dir.path(), "bundle-escape"));
     }
 }
+
+TEST_CASE("A system preset resolves by name from the bundled profiles", "[Preset][Bundle]")
+{
+    ScopedTemporaryDir temp_dir;
+    ScopedDataDir      data(temp_dir.path() / "data");
+    ScopedResourcesDir resources(temp_dir.path() / "resources");
+    write_acme_printer_vendor(temp_dir.path() / "resources" / "profiles", 33.);
+
+    PresetBundle       bundle;
+    DynamicPrintConfig config;
+    std::string        error;
+    REQUIRE(bundle.resolve_system_preset(config, Preset::TYPE_PRINTER, "Acme Printer",
+                                         ForwardCompatibilitySubstitutionRule::EnableSilent, error));
+    CHECK(error.empty());
+    CHECK_THAT(config.opt_float("extruder_clearance_dist_to_rod"), Catch::Matchers::WithinAbs(33., 1e-6));
+}
+
+TEST_CASE("A system preset resolves from the data directory copy of its vendor", "[Preset][Bundle]")
+{
+    ScopedTemporaryDir temp_dir;
+    ScopedDataDir      data(temp_dir.path() / "data");
+    ScopedResourcesDir resources(temp_dir.path() / "resources");
+    write_acme_printer_vendor(temp_dir.path() / "resources" / "profiles", 33.);
+    write_acme_printer_vendor(temp_dir.path() / "data" / PRESET_SYSTEM_DIR, 35.);
+
+    PresetBundle       bundle;
+    DynamicPrintConfig config;
+    std::string        error;
+    REQUIRE(bundle.resolve_system_preset(config, Preset::TYPE_PRINTER, "Acme Printer",
+                                         ForwardCompatibilitySubstitutionRule::EnableSilent, error));
+    CHECK_THAT(config.opt_float("extruder_clearance_dist_to_rod"), Catch::Matchers::WithinAbs(35., 1e-6));
+}
+
+TEST_CASE("A system preset resolves from a vendor shipped as its preset cache alone", "[Preset][Bundle]")
+{
+    ScopedTemporaryDir temp_dir;
+    ScopedDataDir      data(temp_dir.path() / "data");
+    ScopedResourcesDir resources(temp_dir.path() / "resources");
+    const fs::path     profiles = temp_dir.path() / "resources" / "profiles";
+    write_acme_printer_vendor(profiles, 33.);
+
+    PresetBundle writer;
+    writer.set_generate_vendor_caches(true);
+    writer.load_vendor_configs_from_json(profiles.string(), "Acme", PresetBundle::LoadSystem,
+                                         ForwardCompatibilitySubstitutionRule::EnableSilent);
+    REQUIRE(fs::exists(profiles / "Acme.opc"));
+    // Release builds ship the cache and drop the profile JSONs, manifest included.
+    fs::remove(profiles / "Acme.json");
+    fs::remove_all(profiles / "Acme");
+
+    PresetBundle       bundle;
+    DynamicPrintConfig config;
+    std::string        error;
+    REQUIRE(bundle.resolve_system_preset(config, Preset::TYPE_PRINTER, "Acme Printer",
+                                         ForwardCompatibilitySubstitutionRule::EnableSilent, error));
+    CHECK_THAT(config.opt_float("extruder_clearance_dist_to_rod"), Catch::Matchers::WithinAbs(33., 1e-6));
+}
+
+TEST_CASE("A system preset no vendor lists is not resolved", "[Preset][Bundle]")
+{
+    ScopedTemporaryDir temp_dir;
+    ScopedDataDir      data(temp_dir.path() / "data");
+    ScopedResourcesDir resources(temp_dir.path() / "resources");
+    write_acme_printer_vendor(temp_dir.path() / "resources" / "profiles", 33.);
+
+    PresetBundle       bundle;
+    DynamicPrintConfig config;
+    std::string        error;
+    CHECK_FALSE(bundle.resolve_system_preset(config, Preset::TYPE_PRINTER, "Unknown Printer",
+                                             ForwardCompatibilitySubstitutionRule::EnableSilent, error));
+    CHECK_FALSE(error.empty());
+}

tests/libslic3r/test_triangle_selector.cpp

@@ -3,8 +3,6 @@
 #include "libslic3r/TriangleSelector.hpp"
 #include "libslic3r/TriangleMesh.hpp"
 
-#include <algorithm>
-
 using namespace Slic3r;
 
 // A sphere gives well over ExtruderMax original facets, so every extruder state can be assigned
@@ -125,77 +123,3 @@ TEST_CASE("Extruder states match the CONST_FILAMENTS hex encoding", "[TriangleSe
     INFO("Hex " << c.hex << " -> extruder " << c.state);
     REQUIRE(TriangleSelector::has_facets(data, EnforcerBlockerType(c.state)));
 }
-
-// Pack 4-bit codes into a bitstream, least significant bit first, in the order the decoder reads them.
-static std::vector<bool> pack_nibbles(const std::vector<int> &nibbles)
-{
-    std::vector<bool> bitstream;
-    for (const int nibble : nibbles)
-        for (int bit = 0; bit < 4; ++bit)
-            bitstream.push_back((nibble >> bit) & 1);
-    return bitstream;
-}
-
-TEST_CASE("A valid paint stream with nested splits round-trips bit for bit", "[TriangleSelector]")
-{
-    const TriangleMesh mesh = test_mesh();
-
-    TriangleSelector::TriangleSplittingData data;
-    data.triangles_to_split.emplace_back(0, 0);
-    // A three-side split whose children, in stream order, are: a one-side split (side 2) into two
-    // leaves, a two-side split (side 1) into leaves of states 20, 0 and 8, then two plain leaves.
-    const std::vector<int> triangle_0 = {0b0011,
-                                         0b1001, 0b1000, 0b0100,
-                                         0b0110, 0b1100, 0b1111, 20 - 18, 0b0000, 0b1100, 8 - 3,
-                                         0b1000,
-                                         0b0100};
-    data.bitstream = pack_nibbles(triangle_0);
-    data.triangles_to_split.emplace_back(5, int(data.bitstream.size()));
-    const std::vector<bool> triangle_5 = pack_nibbles({0b1100, 3 - 3});
-    data.bitstream.insert(data.bitstream.end(), triangle_5.begin(), triangle_5.end());
-    data.reset_used_states();
-    REQUIRE(data.update_used_states(0));
-
-    TriangleSelector restored(mesh);
-    restored.deserialize(data);
-
-    REQUIRE(restored.num_facets(EnforcerBlockerType::Extruder20) == 1);
-    REQUIRE(restored.num_facets(EnforcerBlockerType::Extruder3) == 1);
-    REQUIRE(restored.serialize() == data);
-}
-
-TEST_CASE("A truncated or malformed paint stream drops only the damaged triangle", "[TriangleSelector][Regression]")
-{
-    struct Case { const char *name; std::vector<int> nibbles; };
-    const auto c = GENERATE(values<Case>({
-        {"three-side split missing two children", {0b0011, 0b1000, 0b1000}},
-        {"leaf missing its state nibble",         {0b1100}},
-        {"leaf missing its second state nibble",  {0b1100, 0b1111}},
-        {"splits nested past the end",            {0b0011, 0xF, 0xF, 0xF, 0xF, 0xF, 0xF, 0xF, 0xF,
-                                                    0xF, 0xF, 0xF, 0xF, 0xF, 0xF, 0xF, 0xF}},
-        {"one-side split of the nonexistent side 3", {0b1101, 0b1000, 0b1000}},
-    }));
-    INFO(c.name);
-
-    const TriangleMesh mesh = test_mesh();
-    TriangleSelector   intact(mesh);
-    intact.set_facet(0, EnforcerBlockerType::Extruder2);
-
-    // Triangle 0 stays intact, triangle 1 carries the damaged stream.
-    TriangleSelector::TriangleSplittingData data = intact.serialize();
-    data.triangles_to_split.emplace_back(1, int(data.bitstream.size()));
-    const std::vector<bool> damaged = pack_nibbles(c.nibbles);
-    data.bitstream.insert(data.bitstream.end(), damaged.begin(), damaged.end());
-
-    TriangleSelector restored(mesh);
-    REQUIRE_NOTHROW(restored.deserialize(data));
-    // Triangle 1 unwinds completely, so the selector holds exactly the intact paint.
-    REQUIRE(restored.serialize() == intact.serialize());
-
-    REQUIRE_NOTHROW(TriangleSelector::has_facets(data, EnforcerBlockerType::Extruder3));
-
-    TriangleSelector::TriangleSplittingData recomputed = data;
-    recomputed.reset_used_states();
-    REQUIRE_FALSE(recomputed.update_used_states(0));
-    REQUIRE(std::none_of(recomputed.used_states.begin(), recomputed.used_states.end(), [](bool used) { return used; }));
-}

tests/slic3rutils/CMakeLists.txt

@@ -18,6 +18,7 @@ add_executable(${_TEST_NAME}_tests
     test_plugin_install.cpp
     test_plugin_lifecycle.cpp
     test_plugin_printer_agent.cpp
+    test_printhost.cpp
     test_slicing_pipeline_bindings.cpp
     test_slicing_pipeline_config.cpp
     test_plugin_sort.cpp

tests/slic3rutils/test_printhost.cpp

@@ -0,0 +1,213 @@
+#include <catch2/catch_all.hpp>
+
+#include <nlohmann/json.hpp>
+
+#include "slic3r/Utils/PrintHost.hpp"
+
+using namespace Slic3r;
+
+namespace {
+
+class TestPrintHost : public PrintHost
+{
+public:
+    using PrintHost::format_error;
+
+    const char* get_name() const override { return "Test"; }
+    bool test(wxString&) const override { return true; }
+    wxString get_test_ok_msg() const override { return {}; }
+    wxString get_test_failed_msg(wxString&) const override { return {}; }
+    bool upload(PrintHostUpload, ProgressFn, ErrorFn, InfoFn) const override { return true; }
+    bool has_auto_discovery() const override { return false; }
+    bool can_test() const override { return false; }
+    PrintHostPostUploadActions get_post_upload_actions() const override { return {}; }
+    std::string get_host() const override { return {}; }
+};
+
+std::string format_error(const std::string& body, const std::string& error, unsigned status)
+{
+    return TestPrintHost().format_error(body, error, status).ToStdString();
+}
+
+std::string envelope(int code, const std::string& message, const std::string& traceback)
+{
+    return nlohmann::json{{"error", {{"code", code}, {"message", message}, {"traceback", traceback}}}}.dump();
+}
+
+std::string moonraker_error(int code, const std::string& message, const std::string& detail = {})
+{
+    std::string line = "tornado.web.HTTPError: HTTP " + std::to_string(code) + ": " + message;
+    if (!detail.empty())
+        line += " (" + detail + ")";
+    return envelope(code, message, "Traceback (most recent call last):\n  ...\n" + line + "\n");
+}
+
+// A real Moonraker body for uploading a file that is being printed.
+constexpr const char* k_busy_file_403 =
+    R"JSON({"error": {"code": 403, "message": "Forbidden", "traceback": "Traceback (most recent call last):\n\n  File \"/home/lava/moonraker/moonraker/components/file_manager/file_manager.py\", line 1017, in _finish_gcode_upload\n    can_start = self._handle_operation_check(check_path)\n                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n\nmoonraker.utils.exceptions.ServerError: File currently in use\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n\n  File \"/home/lava/moonraker/moonraker/components/application.py\", line 1069, in post\n    raise tornado.web.HTTPError(\ntornado.web.HTTPError: HTTP 403: Forbidden (File is loaded, upload not permitted)\n"}})JSON";
+
+} // namespace
+
+TEST_CASE("A Klipper upload error shows its reason instead of a Python traceback", "[PrintHost][Regression]")
+{
+    const std::string msg = format_error(k_busy_file_403, "", 403);
+    INFO("actual: " << msg);
+
+    CHECK(msg == "HTTP 403: Forbidden (File is loaded, upload not permitted)");
+    CHECK_THAT(msg, !Catch::Matchers::ContainsSubstring("Traceback"));
+    CHECK_THAT(msg, !Catch::Matchers::ContainsSubstring("file_manager.py"));
+}
+
+TEST_CASE("The specific cause is recovered from a file endpoint's traceback", "[PrintHost]")
+{
+    SECTION("a plain detail")
+    {
+        const std::string body = moonraker_error(403, "Forbidden", "File is loaded, upload not permitted");
+        CHECK(format_error(body, "", 403) == "HTTP 403: Forbidden (File is loaded, upload not permitted)");
+    }
+
+    SECTION("a detail whose own parentheses nest (a filename)")
+    {
+        const std::string detail = "Directory does not exist (/home/pi/gcodes/plate (1).gcode)";
+        const std::string body   = moonraker_error(400, "Bad Request", detail);
+        CHECK(format_error(body, "", 400) == "HTTP 400: Bad Request (" + detail + ")");
+    }
+
+    SECTION("a detail that contains the reason phrase")
+    {
+        const std::string body = moonraker_error(403, "Forbidden", "Forbidden zone: access denied");
+        CHECK(format_error(body, "", 403) == "HTTP 403: Forbidden (Forbidden zone: access denied)");
+    }
+
+    SECTION("a detail that spans lines")
+    {
+        const std::string detail = "Move out of range\nX=250.000 Y=10.000";
+        const std::string body   = moonraker_error(400, "Bad Request", detail);
+        CHECK(format_error(body, "", 400) == "HTTP 400: Bad Request (" + detail + ")");
+    }
+
+    SECTION("a detail that only repeats the reason phrase is dropped")
+    {
+        const std::string body = moonraker_error(401, "Unauthorized", "Unauthorized");
+        CHECK(format_error(body, "", 401) == "HTTP 401: Unauthorized");
+    }
+}
+
+TEST_CASE("An unhandled exception shows its type and message", "[PrintHost]")
+{
+    const std::string frame = "Traceback (most recent call last):\n"
+                              "  File \"/home/pi/moonraker/moonraker/components/file_manager/file_manager.py\", line 1, in write\n"
+                              "    self._write(data)\n";
+
+    SECTION("a one-line message")
+    {
+        const std::string body = envelope(500, "Internal Server Error", frame + "OSError: [Errno 28] No space left on device\n");
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (OSError: [Errno 28] No space left on device)");
+    }
+
+    SECTION("a message that spans lines")
+    {
+        const std::string body = envelope(500, "Internal Server Error", frame + "ServerError: Klippy request failed\n  see klippy.log\n");
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (ServerError: Klippy request failed\n  see klippy.log)");
+    }
+
+    SECTION("raised while handling an HTTPError with the same code")
+    {
+        const std::string traceback = frame + "tornado.web.HTTPError: HTTP 500: Internal Server Error (Database locked)\n\n"
+                                              "During handling of the above exception, another exception occurred:\n\n" +
+                                      frame + "OSError: [Errno 5] Input/output error\n";
+        const std::string body      = envelope(500, "Internal Server Error", traceback);
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (OSError: [Errno 5] Input/output error)");
+    }
+
+    SECTION("a traceback with no header")
+    {
+        const std::string body = envelope(500, "Internal Server Error", "OSError: [Errno 5] Input/output error");
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (OSError: [Errno 5] Input/output error)");
+    }
+}
+
+TEST_CASE("A reason already complete in message is shown unchanged", "[PrintHost]")
+{
+    SECTION("message is the whole reason, no trailing detail")
+    {
+        const std::string body = moonraker_error(503, "Klippy is not ready");
+        CHECK(format_error(body, "", 503) == "HTTP 503: Klippy is not ready");
+    }
+
+    SECTION("a message that itself contains parentheses is not duplicated")
+    {
+        const std::string reason = "Requested blocks (0-5) are unavailable";
+        const std::string body   = moonraker_error(400, reason);
+        CHECK(format_error(body, "", 400) == "HTTP 400: " + reason);
+    }
+}
+
+TEST_CASE("A Moonraker error with no usable detail shows just the reason phrase", "[PrintHost]")
+{
+    struct Case
+    {
+        const char* name;
+        const char* body;
+        unsigned status;
+        const char* expected;
+    };
+
+    const auto c = GENERATE(
+        Case{"an empty traceback", R"JSON({"error": {"code": 500, "message": "Internal Server Error", "traceback": ""}})JSON", 500,
+             "HTTP 500: Internal Server Error"},
+        Case{"a traceback of only whitespace", R"JSON({"error": {"code": 500, "message": "Internal Server Error", "traceback": "\n \n"}})JSON",
+             500, "HTTP 500: Internal Server Error"});
+
+    DYNAMIC_SECTION(c.name) { CHECK(format_error(c.body, "", c.status) == c.expected); }
+}
+
+TEST_CASE("A percent sign in the reason is not a format specifier", "[PrintHost]")
+{
+    const std::string body = moonraker_error(507, "Insufficient Storage", "disk 100% full");
+    CHECK(format_error(body, "", 507) == "HTTP 507: Insufficient Storage (disk 100% full)");
+}
+
+TEST_CASE("Error bodies that are not a Moonraker envelope are left unchanged", "[PrintHost]")
+{
+    SECTION("OctoPrint's string-valued error member")
+    {
+        const std::string body = R"JSON({"error": "File not found"})JSON";
+        CHECK(format_error(body, "", 404) == "HTTP 404: " + body);
+    }
+
+    SECTION("PrusaLink's top-level message, not under error")
+    {
+        const std::string body = R"JSON({"title": "Conflict", "message": "Printer is printing"})JSON";
+        CHECK(format_error(body, "", 409) == "HTTP 409: " + body);
+    }
+
+    SECTION("a body that is not JSON")
+    {
+        const std::string html = "<html><head><title>502 Bad Gateway</title></head></html>";
+        CHECK(format_error(html, "", 502) == "HTTP 502: " + html);
+    }
+
+    SECTION("an error object with no traceback")
+    {
+        const std::string body = R"JSON({"error": {"code": 500, "message": "Internal Server Error"}})JSON";
+        CHECK(format_error(body, "", 500) == "HTTP 500: " + body);
+    }
+
+    SECTION("an error object whose traceback is null")
+    {
+        const std::string body = R"JSON({"error": {"code": 500, "message": "Internal Server Error", "traceback": null}})JSON";
+        CHECK(format_error(body, "", 500) == "HTTP 500: " + body);
+    }
+
+    SECTION("an envelope whose reason phrase is empty")
+    {
+        const std::string body = envelope(403, "", "Traceback (most recent call last):\nOSError: denied\n");
+        CHECK(format_error(body, "", 403) == "HTTP 403: " + body);
+    }
+
+    SECTION("a transport error with no HTTP status")
+    {
+        CHECK(format_error("", "curl:Could not connect", 0) == "curl:Could not connect");
+    }
+}