From e06404bd08a6cc5dab621b455fe69767c7d13497 Mon Sep 17 00:00:00 2001
From: Siarhei Fedartsou <siarhei.fedartsou@gmail.com>
Date: Fri, 21 Jun 2024 21:04:56 +0200
Subject: [PATCH] Add more test cases

---
 unit_tests/engine/polyline_compressor.cpp | 92 +++++++++++++++++++++++
 1 file changed, 92 insertions(+)

diff --git a/unit_tests/engine/polyline_compressor.cpp b/unit_tests/engine/polyline_compressor.cpp
index fa05512a9..e2a9a5fd7 100644
--- a/unit_tests/engine/polyline_compressor.cpp
+++ b/unit_tests/engine/polyline_compressor.cpp
@@ -45,4 +45,96 @@ BOOST_AUTO_TEST_CASE(polyline6_test_case)
         decodePolyline<1000000>(encodePolyline<1000000>(coords.begin(), coords.end())).begin()));
 }
 
+BOOST_AUTO_TEST_CASE(empty_polyline_test)
+{
+    using namespace osrm::engine;
+    using namespace osrm::util;
+
+    std::vector<Coordinate> empty_coords;
+    BOOST_CHECK_EQUAL(encodePolyline(empty_coords.begin(), empty_coords.end()), "");
+    BOOST_CHECK(decodePolyline("").empty());
+}
+BOOST_AUTO_TEST_CASE(polyline_single_point_test)
+{
+    using namespace osrm::engine;
+    using namespace osrm::util;
+
+    const std::vector<Coordinate> coords({{FixedLongitude{-122414000}, FixedLatitude{37776000}}});
+
+    const std::string encoded = encodePolyline(coords.begin(), coords.end());
+    BOOST_CHECK_EQUAL(encoded, "_cqeFn~cjV");
+
+    const auto decoded = decodePolyline(encoded);
+    BOOST_CHECK_EQUAL(decoded.size(), 1);
+    BOOST_CHECK_EQUAL(decoded[0].lon, FixedLongitude{-122414000});
+    BOOST_CHECK_EQUAL(decoded[0].lat, FixedLatitude{37776000});
+}
+
+BOOST_AUTO_TEST_CASE(polyline_multiple_points_test)
+{
+    using namespace osrm::engine;
+    using namespace osrm::util;
+
+    const std::vector<Coordinate> coords({{FixedLongitude{-122414000}, FixedLatitude{37776000}},
+                                          {FixedLongitude{-122420000}, FixedLatitude{37779000}},
+                                          {FixedLongitude{-122421000}, FixedLatitude{37780000}}});
+
+    const std::string encoded = encodePolyline(coords.begin(), coords.end());
+    BOOST_CHECK_EQUAL(encoded, "_cqeFn~cjVwQnd@gEfE");
+
+    const auto decoded = decodePolyline(encoded);
+    BOOST_CHECK_EQUAL(decoded.size(), 3);
+    for (size_t i = 0; i < coords.size(); ++i)
+    {
+        BOOST_CHECK_EQUAL(decoded[i].lon, coords[i].lon);
+        BOOST_CHECK_EQUAL(decoded[i].lat, coords[i].lat);
+    }
+}
+
+BOOST_AUTO_TEST_CASE(polyline_large_coordinate_difference_test)
+{
+    using namespace osrm::engine;
+    using namespace osrm::util;
+
+    const std::vector<Coordinate> coords({{FixedLongitude{-179000000}, FixedLatitude{-89000000}},
+                                          {FixedLongitude{179000000}, FixedLatitude{89000000}}});
+
+    const std::string encoded = encodePolyline(coords.begin(), coords.end());
+    BOOST_CHECK_EQUAL(encoded, "~xe~O~|oca@_sl}`@_{`hcA");
+
+    const auto decoded = decodePolyline(encoded);
+    BOOST_CHECK_EQUAL(decoded.size(), 2);
+    for (size_t i = 0; i < coords.size(); ++i)
+    {
+        BOOST_CHECK_EQUAL(decoded[i].lon, coords[i].lon);
+        BOOST_CHECK_EQUAL(decoded[i].lat, coords[i].lat);
+    }
+}
+
+BOOST_AUTO_TEST_CASE(roundtrip)
+{
+    using namespace osrm::engine;
+    using namespace osrm::util;
+
+    {
+        const auto encoded = "_chxEn`zvN\\\\]]";
+        const auto decoded = decodePolyline(encoded);
+        const auto reencoded = encodePolyline(decoded.begin(), decoded.end());
+        BOOST_CHECK_EQUAL(encoded, reencoded);
+    }
+    {
+        const auto encoded =
+            "gcneIpgxzRcDnBoBlEHzKjBbHlG`@`IkDxIiKhKoMaLwTwHeIqHuAyGXeB~Ew@fFjAtIzExF";
+        const auto decoded = decodePolyline(encoded);
+        const auto reencoded = encodePolyline(decoded.begin(), decoded.end());
+        BOOST_CHECK_EQUAL(encoded, reencoded);
+    }
+    {
+        const auto encoded = "_p~iF~ps|U_ulLnnqC_mqNvxq`@";
+        const auto decoded = decodePolyline(encoded);
+        const auto reencoded = encodePolyline(decoded.begin(), decoded.end());
+        BOOST_CHECK_EQUAL(encoded, reencoded);
+    }
+}
+
 BOOST_AUTO_TEST_SUITE_END()