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

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);
+}