[M6] tests: levenshtein + pc_scan + brute_scan + findmodule_scan + last_failure_dir + cmd_linkdb_add + codegen PkgConfig/brute-force

build/CMakeLists.txt

@@ -91,6 +91,15 @@ target_link_libraries(cargoxx_bin PRIVATE
 # ----- tests -----
 enable_testing()
 include(Catch)
+add_executable(test_brute_scan_parse ../tests/brute_scan_parse.cpp)
+target_link_libraries(test_brute_scan_parse PRIVATE
+    cargoxx
+    reproc
+    SQLite::SQLite3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_brute_scan_parse)
 add_executable(test_cmd_add ../tests/cmd_add.cpp)
 target_link_libraries(test_cmd_add PRIVATE
     cargoxx
@@ -118,6 +127,15 @@ target_link_libraries(test_cmd_clean PRIVATE
     Catch2::Catch2WithMain
 )
 catch_discover_tests(test_cmd_clean)
+add_executable(test_cmd_linkdb_add ../tests/cmd_linkdb_add.cpp)
+target_link_libraries(test_cmd_linkdb_add PRIVATE
+    cargoxx
+    reproc
+    SQLite::SQLite3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_linkdb_add)
 add_executable(test_cmd_new ../tests/cmd_new.cpp)
 target_link_libraries(test_cmd_new PRIVATE
     cargoxx
@@ -208,6 +226,24 @@ target_link_libraries(test_exec_run PRIVATE
     Catch2::Catch2WithMain
 )
 catch_discover_tests(test_exec_run)
+add_executable(test_findmodule_scan_live ../tests/findmodule_scan_live.cpp)
+target_link_libraries(test_findmodule_scan_live PRIVATE
+    cargoxx
+    reproc
+    SQLite::SQLite3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_findmodule_scan_live)
+add_executable(test_last_failure_dir ../tests/last_failure_dir.cpp)
+target_link_libraries(test_last_failure_dir PRIVATE
+    cargoxx
+    reproc
+    SQLite::SQLite3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_last_failure_dir)
 add_executable(test_layout_discovery ../tests/layout_discovery.cpp)
 target_link_libraries(test_layout_discovery PRIVATE
     cargoxx
@@ -217,6 +253,15 @@ target_link_libraries(test_layout_discovery PRIVATE
     Catch2::Catch2WithMain
 )
 catch_discover_tests(test_layout_discovery)
+add_executable(test_levenshtein ../tests/levenshtein.cpp)
+target_link_libraries(test_levenshtein PRIVATE
+    cargoxx
+    reproc
+    SQLite::SQLite3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_levenshtein)
 add_executable(test_linkdb_lookup ../tests/linkdb_lookup.cpp)
 target_link_libraries(test_linkdb_lookup PRIVATE
     cargoxx
@@ -307,6 +352,15 @@ target_link_libraries(test_nixpkgs_probe_parse PRIVATE
     Catch2::Catch2WithMain
 )
 catch_discover_tests(test_nixpkgs_probe_parse)
+add_executable(test_pc_scan_parse ../tests/pc_scan_parse.cpp)
+target_link_libraries(test_pc_scan_parse PRIVATE
+    cargoxx
+    reproc
+    SQLite::SQLite3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_pc_scan_parse)
 add_executable(test_semver_satisfies ../tests/semver_satisfies.cpp)
 target_link_libraries(test_semver_satisfies PRIVATE
     cargoxx

tests/brute_scan_parse.cpp

@@ -0,0 +1,89 @@
+#include <catch2/catch_test_macros.hpp>
+
+import cargoxx.resolver;
+import cargoxx.util;
+import std;
+
+using cargoxx::resolver::brute_scan;
+using cargoxx::util::ErrorCode;
+
+namespace {
+
+auto fresh_store() -> std::filesystem::path {
+    auto d = std::filesystem::temp_directory_path() /
+             std::format("cargoxx-brute-scan-{}", std::random_device{}());
+    std::filesystem::create_directories(d / "lib");
+    std::filesystem::create_directories(d / "include");
+    return d;
+}
+
+void touch_lib(const std::filesystem::path& store, std::string_view name) {
+    std::ofstream{store / "lib" / std::string{name}};
+}
+
+void touch_include(const std::filesystem::path& store, std::string_view rel) {
+    auto p = store / "include" / rel;
+    std::filesystem::create_directories(p.parent_path());
+    std::ofstream{p};
+}
+
+} // namespace
+
+TEST_CASE("brute_scan collects lib*.a and lib*.so files",
+          "[resolver][brute_scan]") {
+    auto store = fresh_store();
+    touch_lib(store, "libfoo.a");
+    touch_lib(store, "libbar.so");
+    touch_lib(store, "libbaz.so.1.2.3");
+    touch_lib(store, "not-a-lib.txt");
+    touch_include(store, "foo.h");
+
+    auto r = brute_scan(store, "foo");
+    REQUIRE(r.has_value());
+    REQUIRE(r->lib_files.size() == 3);
+    auto has = [&](std::string_view suffix) {
+        return std::ranges::any_of(r->lib_files, [&](const auto& p) {
+            return std::string_view{p}.ends_with(suffix);
+        });
+    };
+    REQUIRE(has("libfoo.a"));
+    REQUIRE(has("libbar.so"));
+    REQUIRE(has("libbaz.so.1.2.3"));
+}
+
+TEST_CASE("brute_scan exposes include/ as a single search directory",
+          "[resolver][brute_scan]") {
+    auto store = fresh_store();
+    touch_lib(store, "libsdl.a");
+    touch_include(store, "SDL2/SDL.h");
+    touch_include(store, "SDL2/SDL_video.h");
+
+    auto r = brute_scan(store, "sdl");
+    REQUIRE(r.has_value());
+    REQUIRE(r->include_dirs.size() == 1);
+    REQUIRE(std::string_view{r->include_dirs[0]}.ends_with("/include"));
+}
+
+TEST_CASE("brute_scan errors when neither libs nor headers are present",
+          "[resolver][brute_scan]") {
+    auto d = std::filesystem::temp_directory_path() /
+             std::format("cargoxx-brute-empty-{}", std::random_device{}());
+    std::filesystem::create_directories(d);
+
+    auto r = brute_scan(d, "ghost");
+    REQUIRE_FALSE(r.has_value());
+    REQUIRE(r.error().code == ErrorCode::ResolutionUnknownPackage);
+}
+
+TEST_CASE("brute_scan emits sorted lib paths for deterministic codegen",
+          "[resolver][brute_scan]") {
+    auto store = fresh_store();
+    touch_lib(store, "libzz.a");
+    touch_lib(store, "libaa.a");
+    touch_lib(store, "libmm.so");
+
+    auto r = brute_scan(store, "x");
+    REQUIRE(r.has_value());
+    REQUIRE(r->lib_files.size() == 3);
+    REQUIRE(std::ranges::is_sorted(r->lib_files));
+}

tests/cmd_linkdb_add.cpp

@@ -0,0 +1,65 @@
+#include <catch2/catch_test_macros.hpp>
+
+import cargoxx.cli;
+import cargoxx.linkdb;
+import cargoxx.util;
+import std;
+
+using cargoxx::cli::cmd_linkdb_add;
+using cargoxx::linkdb::Database;
+
+namespace {
+
+auto fresh_overlay() -> std::filesystem::path {
+    auto d = std::filesystem::temp_directory_path() /
+             std::format("cargoxx-linkdb-add-test-{}", std::random_device{}());
+    std::filesystem::create_directories(d);
+    return d / "overlay.sqlite";
+}
+
+} // namespace
+
+TEST_CASE("cmd_linkdb_add inserts a recipe that resolve() can read back",
+          "[cli][linkdb_add]") {
+    auto overlay = fresh_overlay();
+
+    auto r = cmd_linkdb_add(
+        "sqlite3", "*", "SQLite3 REQUIRED", {"SQLite::SQLite3"}, "sqlite",
+        overlay);
+    REQUIRE(r.has_value());
+
+    auto db = Database::open(overlay);
+    REQUIRE(db.has_value());
+    auto rec = db->resolve("sqlite3", "*");
+    REQUIRE(rec.has_value());
+    REQUIRE(rec->source == "manual");
+    REQUIRE(rec->find_package == "SQLite3 REQUIRED");
+    REQUIRE(rec->targets == std::vector<std::string>{"SQLite::SQLite3"});
+    REQUIRE(rec->nixpkgs_attr == "sqlite");
+}
+
+TEST_CASE("cmd_linkdb_add evicts auto-discovered rows for the same package",
+          "[cli][linkdb_add]") {
+    auto overlay = fresh_overlay();
+    auto db = Database::open(overlay);
+    REQUIRE(db.has_value());
+
+    // Seed an auto-source row first.
+    cargoxx::linkdb::Recipe auto_recipe{
+        .nixpkgs_attr = "sqlite",
+        .find_package = "auto CONFIG REQUIRED",
+        .targets = {"auto::auto"},
+        .source = "nix-probe",
+    };
+    REQUIRE(db->insert_provisional("sqlite3", "*", auto_recipe, "nix-probe")
+                .has_value());
+    REQUIRE(db->confirm_provisional("sqlite3", "*", "nix-probe").has_value());
+
+    REQUIRE(cmd_linkdb_add("sqlite3", "*", "SQLite3 REQUIRED",
+                             {"SQLite::SQLite3"}, "sqlite", overlay)
+                .has_value());
+
+    auto rec = db->resolve("sqlite3", "*");
+    REQUIRE(rec.has_value());
+    REQUIRE(rec->source == "manual");
+}

tests/codegen_cmake.cpp

@@ -342,3 +342,70 @@ TEST_CASE("cmake_lists threads dev_recipes through find_package and tests",
     auto block = out.substr(link, end - link);
     REQUIRE(block.find("Catch2::Catch2WithMain") != std::string::npos);
 }
+
+TEST_CASE("cmake_lists emits pkg_check_modules for pkg_config recipes",
+          "[codegen][cmake]") {
+    Manifest m{
+        .package = pkg("app"),
+        .dependencies = {{.name = "sqlite", .version_spec = "*"}},
+    };
+    DiscoveredLayout layout{
+        .library = std::nullopt,
+        .binaries = {src_target(TargetKind::Binary, "app", "src/main.cpp")},
+        .tests = {},
+        .examples = {},
+    };
+    Lockfile lock = lock_minimal();
+    Recipe sqlite{
+        .nixpkgs_attr = "sqlite",
+        .find_package = "PkgConfig REQUIRED",
+        .targets = {"PkgConfig::SQLITE3"},
+        .source = "pkg-config",
+        .pkg_config_module = "sqlite3",
+    };
+    GenerateInputs in{m, layout, lock, {sqlite}, {}, ROOT};
+
+    auto out = cmake_lists(in);
+    REQUIRE(out.find("find_package(PkgConfig REQUIRED)") != std::string::npos);
+    REQUIRE(out.find("pkg_check_modules(SQLITE3 REQUIRED IMPORTED_TARGET sqlite3)") !=
+            std::string::npos);
+    auto link = out.find("target_link_libraries(app_bin PRIVATE");
+    REQUIRE(link != std::string::npos);
+    auto block = out.substr(link, out.find(')', link) - link);
+    REQUIRE(block.find("PkgConfig::SQLITE3") != std::string::npos);
+}
+
+TEST_CASE("cmake_lists synthesizes INTERFACE IMPORTED target for brute-force "
+          "recipes",
+          "[codegen][cmake]") {
+    Manifest m{
+        .package = pkg("app"),
+        .dependencies = {{.name = "obscure", .version_spec = "*"}},
+    };
+    DiscoveredLayout layout{
+        .library = std::nullopt,
+        .binaries = {src_target(TargetKind::Binary, "app", "src/main.cpp")},
+        .tests = {},
+        .examples = {},
+    };
+    Lockfile lock = lock_minimal();
+    Recipe brute{
+        .nixpkgs_attr = "obscure",
+        .find_package = "",
+        .targets = {"obscure::obscure"},
+        .source = "brute-force",
+        .brute_force_libs = {"/nix/store/abc-obscure/lib/libobscure.a"},
+        .brute_force_includes = {"/nix/store/abc-obscure/include"},
+    };
+    GenerateInputs in{m, layout, lock, {brute}, {}, ROOT};
+
+    auto out = cmake_lists(in);
+    REQUIRE(out.find("add_library(obscure::obscure INTERFACE IMPORTED)") !=
+            std::string::npos);
+    REQUIRE(out.find("INTERFACE_LINK_LIBRARIES") != std::string::npos);
+    REQUIRE(out.find("/nix/store/abc-obscure/lib/libobscure.a") !=
+            std::string::npos);
+    REQUIRE(out.find("INTERFACE_INCLUDE_DIRECTORIES") != std::string::npos);
+    REQUIRE(out.find("/nix/store/abc-obscure/include") != std::string::npos);
+    REQUIRE(out.find("find_package()") == std::string::npos);
+}

tests/codegen_flake.cpp

@@ -73,6 +73,37 @@ auto dep_pkg(std::string name, std::string version,
 
 } // namespace
 
+TEST_CASE("flake_nix adds pkgs.pkg-config to nativeBuildInputs only when needed",
+          "[codegen][flake]") {
+    Manifest m{pkg("app"), {dep("sqlite", "*")}, {}};
+    DiscoveredLayout layout{};
+    Lockfile lock{1, {root_pkg("app", "0.1.0")}};
+    std::vector<Recipe> recipes = {Recipe{
+        .nixpkgs_attr = "sqlite",
+        .find_package = "PkgConfig REQUIRED",
+        .targets = {"PkgConfig::SQLITE3"},
+        .source = "pkg-config",
+        .pkg_config_module = "sqlite3",
+    }};
+    GenerateInputs in{m, layout, lock, recipes, {}, "/tmp/app"};
+
+    auto out = flake_nix(in);
+    REQUIRE(out.find("pkgs.pkg-config") != std::string::npos);
+    REQUIRE(out.find("pkgs.sqlite") != std::string::npos);
+}
+
+TEST_CASE("flake_nix omits pkgs.pkg-config when no recipe needs it",
+          "[codegen][flake]") {
+    Manifest m{pkg("hello"), {dep("fmt", "*")}, {}};
+    DiscoveredLayout layout{};
+    Lockfile lock{1, {root_pkg("hello", "0.1.0")}};
+    std::vector<Recipe> recipes = {recipe("fmt_10")};
+    GenerateInputs in{m, layout, lock, recipes, {}, "/tmp/hello"};
+
+    auto out = flake_nix(in);
+    REQUIRE(out.find("pkgs.pkg-config") == std::string::npos);
+}
+
 TEST_CASE("flake_nix always emits the shared nixos-unstable nixpkgs input",
           "[codegen][flake]") {
     Manifest m{pkg("hello"), {}, {}};

tests/findmodule_scan_live.cpp

@@ -0,0 +1,67 @@
+#include <catch2/catch_test_macros.hpp>
+
+import cargoxx.resolver;
+import cargoxx.util;
+import std;
+
+using cargoxx::resolver::findmodule_scan;
+using cargoxx::util::ErrorCode;
+
+// `findmodule_scan` shells out to `cmake -P` to discover CMAKE_ROOT.
+// Gate the test on the same env var we use for other live probes so
+// CI without cmake can still pass.
+namespace {
+
+auto live_tests_enabled() -> bool {
+    auto* e = std::getenv("CARGOXX_NETWORK_TESTS");
+    return e != nullptr && *e != 0;
+}
+
+} // namespace
+
+TEST_CASE("findmodule_scan picks FindSQLite3 for 'sqlite'",
+          "[resolver][findmodule_scan][live]") {
+    if (!live_tests_enabled()) {
+        SKIP("CARGOXX_NETWORK_TESTS not set");
+    }
+    auto r = findmodule_scan("sqlite");
+    REQUIRE(r.has_value());
+    REQUIRE(r->find_package == "SQLite3 REQUIRED");
+    REQUIRE_FALSE(r->targets.empty());
+    auto has = [&](std::string_view t) {
+        return std::ranges::find(r->targets, std::string{t}) != r->targets.end();
+    };
+    REQUIRE((has("SQLite3::SQLite3") || has("SQLite::SQLite3")));
+    REQUIRE(r->module_file.filename() == "FindSQLite3.cmake");
+}
+
+TEST_CASE("findmodule_scan picks FindZLIB for 'zlib'",
+          "[resolver][findmodule_scan][live]") {
+    if (!live_tests_enabled()) {
+        SKIP("CARGOXX_NETWORK_TESTS not set");
+    }
+    auto r = findmodule_scan("zlib");
+    REQUIRE(r.has_value());
+    REQUIRE(r->find_package == "ZLIB REQUIRED");
+    REQUIRE(r->module_file.filename() == "FindZLIB.cmake");
+}
+
+TEST_CASE("findmodule_scan picks FindThreads for 'threads'",
+          "[resolver][findmodule_scan][live]") {
+    if (!live_tests_enabled()) {
+        SKIP("CARGOXX_NETWORK_TESTS not set");
+    }
+    auto r = findmodule_scan("threads");
+    REQUIRE(r.has_value());
+    REQUIRE(r->find_package == "Threads REQUIRED");
+}
+
+TEST_CASE("findmodule_scan errors for a totally unknown name",
+          "[resolver][findmodule_scan][live]") {
+    if (!live_tests_enabled()) {
+        SKIP("CARGOXX_NETWORK_TESTS not set");
+    }
+    auto r = findmodule_scan("definitelynotacmaketmodule12345");
+    REQUIRE_FALSE(r.has_value());
+    REQUIRE(r.error().code == ErrorCode::ResolutionUnknownPackage);
+}

tests/last_failure_dir.cpp

@@ -0,0 +1,59 @@
+#include <catch2/catch_test_macros.hpp>
+
+import cargoxx.resolver;
+import std;
+
+using cargoxx::resolver::last_failure_dir;
+
+namespace {
+
+struct EnvScope {
+    EnvScope(const char* k, std::optional<std::string> v) : key(k) {
+        if (auto* prior = std::getenv(key)) {
+            previous = std::string{prior};
+        }
+        if (v) {
+            setenv(key, v->c_str(), 1);
+        } else {
+            unsetenv(key);
+        }
+    }
+    ~EnvScope() {
+        if (previous) {
+            setenv(key, previous->c_str(), 1);
+        } else {
+            unsetenv(key);
+        }
+    }
+    const char* key;
+    std::optional<std::string> previous;
+};
+
+} // namespace
+
+TEST_CASE("last_failure_dir honors XDG_CACHE_HOME when set",
+          "[resolver][last_failure_dir]") {
+    EnvScope xdg{"XDG_CACHE_HOME", "/tmp/xdg-test"};
+
+    auto p = last_failure_dir("sqlite");
+    REQUIRE(p.string() == "/tmp/xdg-test/cargoxx/last-failure/sqlite");
+}
+
+TEST_CASE("last_failure_dir falls back to $HOME/.cache when XDG is unset",
+          "[resolver][last_failure_dir]") {
+    EnvScope xdg{"XDG_CACHE_HOME", std::nullopt};
+    EnvScope home{"HOME", "/tmp/home-test"};
+
+    auto p = last_failure_dir("fmt");
+    REQUIRE(p.string() == "/tmp/home-test/.cache/cargoxx/last-failure/fmt");
+}
+
+TEST_CASE("last_failure_dir uses cwd-based fallback when neither var is set",
+          "[resolver][last_failure_dir]") {
+    EnvScope xdg{"XDG_CACHE_HOME", std::nullopt};
+    EnvScope home{"HOME", std::nullopt};
+
+    auto p = last_failure_dir("obscure");
+    REQUIRE(p.filename() == "obscure");
+    REQUIRE(p.parent_path().filename() == ".cargoxx-last-failure");
+}

tests/levenshtein.cpp

@@ -0,0 +1,36 @@
+#include <catch2/catch_test_macros.hpp>
+
+import cargoxx.util;
+import std;
+
+using cargoxx::util::levenshtein;
+
+TEST_CASE("levenshtein of equal strings is zero", "[util][levenshtein]") {
+    REQUIRE(levenshtein("", "") == 0);
+    REQUIRE(levenshtein("sqlite", "sqlite") == 0);
+}
+
+TEST_CASE("levenshtein counts a single suffix character", "[util][levenshtein]") {
+    REQUIRE(levenshtein("sqlite", "sqlite3") == 1);
+    REQUIRE(levenshtein("fmt", "fmtlib") == 3);
+}
+
+TEST_CASE("levenshtein is symmetric", "[util][levenshtein]") {
+    REQUIRE(levenshtein("sqlite", "sqlite3") == levenshtein("sqlite3", "sqlite"));
+    REQUIRE(levenshtein("abseil-cpp", "absl") == levenshtein("absl", "abseil-cpp"));
+}
+
+TEST_CASE("levenshtein counts a single substitution", "[util][levenshtein]") {
+    REQUIRE(levenshtein("kitten", "sitten") == 1);
+    REQUIRE(levenshtein("kitten", "kittes") == 1);
+}
+
+TEST_CASE("levenshtein matches the classic kitten/sitting example",
+          "[util][levenshtein]") {
+    REQUIRE(levenshtein("kitten", "sitting") == 3);
+}
+
+TEST_CASE("levenshtein handles empty inputs", "[util][levenshtein]") {
+    REQUIRE(levenshtein("", "abc") == 3);
+    REQUIRE(levenshtein("abc", "") == 3);
+}

tests/pc_scan_parse.cpp

@@ -0,0 +1,89 @@
+#include <catch2/catch_test_macros.hpp>
+
+import cargoxx.resolver;
+import cargoxx.util;
+import std;
+
+using cargoxx::resolver::pc_scan;
+using cargoxx::util::ErrorCode;
+
+namespace {
+
+auto fresh_store() -> std::filesystem::path {
+    auto d = std::filesystem::temp_directory_path() /
+             std::format("cargoxx-pc-scan-{}", std::random_device{}());
+    std::filesystem::create_directories(d / "lib" / "pkgconfig");
+    return d;
+}
+
+void touch_pc(const std::filesystem::path& store, std::string_view name,
+              std::string_view content =
+                  "Name: x\nDescription: x\nLibs: -lx\n") {
+    std::ofstream{store / "lib" / "pkgconfig" / std::string{name}} << content;
+}
+
+} // namespace
+
+TEST_CASE("pc_scan picks the exact-name .pc when present",
+          "[resolver][pc_scan]") {
+    auto store = fresh_store();
+    touch_pc(store, "sqlite3.pc");
+
+    auto r = pc_scan(store, "sqlite3");
+    REQUIRE(r.has_value());
+    REQUIRE(r->pc_module == "sqlite3");
+    REQUIRE(r->pc_file.filename() == "sqlite3.pc");
+}
+
+TEST_CASE("pc_scan picks sqlite3.pc for nixpkgs name 'sqlite'",
+          "[resolver][pc_scan]") {
+    auto store = fresh_store();
+    touch_pc(store, "sqlite3.pc");
+
+    auto r = pc_scan(store, "sqlite");
+    REQUIRE(r.has_value());
+    REQUIRE(r->pc_module == "sqlite3");
+}
+
+TEST_CASE("pc_scan picks the best match among multiple .pc files",
+          "[resolver][pc_scan]") {
+    auto store = fresh_store();
+    touch_pc(store, "zlib.pc");
+    touch_pc(store, "sqlite3.pc");
+    touch_pc(store, "unrelated.pc");
+
+    auto r = pc_scan(store, "zlib");
+    REQUIRE(r.has_value());
+    REQUIRE(r->pc_module == "zlib");
+}
+
+TEST_CASE("pc_scan returns ResolutionUnknownPackage when nothing matches",
+          "[resolver][pc_scan]") {
+    auto store = fresh_store();
+    touch_pc(store, "totally-unrelated.pc");
+
+    auto r = pc_scan(store, "sqlite");
+    REQUIRE_FALSE(r.has_value());
+    REQUIRE(r.error().code == ErrorCode::ResolutionUnknownPackage);
+}
+
+TEST_CASE("pc_scan errors when lib/pkgconfig is missing",
+          "[resolver][pc_scan]") {
+    auto d = std::filesystem::temp_directory_path() /
+             std::format("cargoxx-pc-empty-{}", std::random_device{}());
+    std::filesystem::create_directories(d);
+
+    auto r = pc_scan(d, "sqlite");
+    REQUIRE_FALSE(r.has_value());
+    REQUIRE(r.error().code == ErrorCode::ResolutionUnknownPackage);
+}
+
+TEST_CASE("pc_scan skips .pc files that look like junk",
+          "[resolver][pc_scan]") {
+    auto store = fresh_store();
+    touch_pc(store, "sqlite3.pc", "this is not a real pc file\n");
+
+    auto r = pc_scan(store, "sqlite3");
+    REQUIRE_FALSE(r.has_value());
+    REQUIRE(r.error().code == ErrorCode::ResolutionUnknownPackage);
+}