osrm-backend/test/t/io/test_string_table.cpp

#include "catch.hpp"

#include <osmium/io/detail/string_table.hpp>

TEST_CASE("Empty StringStore") {
    const osmium::io::detail::StringStore ss{100};

    REQUIRE(ss.begin() == ss.end());
    REQUIRE(ss.get_chunk_size() == 100);
    REQUIRE(ss.get_chunk_count() == 1);
}

TEST_CASE("Add zero-length string to StringStore") {
    osmium::io::detail::StringStore ss{100};

    const char* s1 = ss.add("");
    REQUIRE(std::string(s1) == "");

    auto it = ss.begin();
    REQUIRE(s1 == *it);
    REQUIRE(std::string(*it) == "");
    REQUIRE(++it == ss.end());

    REQUIRE(ss.get_chunk_count() == 1);
}

TEST_CASE("Add strings to StringStore") {
    osmium::io::detail::StringStore ss{100};

    const char* s1 = ss.add("foo");
    const char* s2 = ss.add("bar");
    REQUIRE(s1 != s2);
    REQUIRE(std::string(s1) == "foo");
    REQUIRE(std::string(s2) == "bar");

    auto it = ss.begin();
    REQUIRE(s1 == *it++);
    REQUIRE(s2 == *it++);
    REQUIRE(it == ss.end());

    ss.clear();
    REQUIRE(ss.begin() == ss.end());
}

TEST_CASE("Add zero-length string and longer strings to StringStore") {
    osmium::io::detail::StringStore ss{100};

    ss.add("");
    ss.add("xxx");
    ss.add("yyyyy");

    auto it = ss.begin();
    REQUIRE(std::string(*it++) == "");
    REQUIRE(std::string(*it++) == "xxx");
    REQUIRE(std::string(*it++) == "yyyyy");
    REQUIRE(it == ss.end());
}

TEST_CASE("Add many strings to StringStore") {
    osmium::io::detail::StringStore ss{100};

    for (const char* teststring : {"", "a", "abc", "abcd", "abcde"}) {
        int i = 0;
        for (; i < 200; ++i) {
            ss.add(teststring);
        }

        for (const char* s : ss) {
            REQUIRE(std::string(s) == teststring);
            --i;
        }

        REQUIRE(i == 0);
        REQUIRE(ss.get_chunk_count() > 1);
        ss.clear();
        REQUIRE(ss.get_chunk_count() == 1);
    }
}

TEST_CASE("Empty StringTable") {
    const osmium::io::detail::StringTable st;

    REQUIRE(st.size() == 1);
    REQUIRE(std::next(st.begin()) == st.end());
}

TEST_CASE("Add strings to StringTable") {
    osmium::io::detail::StringTable st;

    REQUIRE(st.add("foo") == 1);
    REQUIRE(st.add("bar") == 2);
    REQUIRE(st.add("bar") == 2);
    REQUIRE(st.add("baz") == 3);
    REQUIRE(st.add("foo") == 1);
    REQUIRE(st.size() == 4);

    auto it = st.begin();
    REQUIRE(std::string("") == *it++);
    REQUIRE(std::string("foo") == *it++);
    REQUIRE(std::string("bar") == *it++);
    REQUIRE(std::string("baz") == *it++);
    REQUIRE(it == st.end());

    st.clear();
    REQUIRE(st.size() == 1);
}

TEST_CASE("Add empty string to StringTable") {
    osmium::io::detail::StringTable st;

    REQUIRE(st.add("") == 1);
    REQUIRE(st.size() == 2);
    REQUIRE(st.add("") == 1);
    REQUIRE(st.size() == 2);
}

TEST_CASE("Lots of strings in string table so chunk overflows") {
    osmium::io::detail::StringTable st{100};
    REQUIRE(st.size() == 1);

    const int n = 1000;
    for (int i = 0; i < n; ++i) {
        const auto s = std::to_string(i);
        st.add(s.c_str());
    }

    REQUIRE(st.size() == n + 1);

    auto it = st.begin();
    REQUIRE(std::string{} == *it++);
    for (int i = 0; i < n; ++i) {
        REQUIRE(std::atoi(*it++) == i);
    }
    REQUIRE(it == st.end());
}