add a basic benchmark for lexer

I suspect std::regex is _horribly_ slow.
Will compare it to boost::regex, then decide.

2 files changed, 37 insertions, 0 deletions

diff --git a/test/benchmarks/CMakeLists.txt b/test/benchmarks/CMakeLists.txt
new file mode 100644
index 0000000..89d9858
--- /dev/null
+++ b/test/benchmarks/CMakeLists.txt
@@ -0,0 +1,12 @@
+add_executable(benchmarks lexer.cpp)
+set_target_properties(benchmarks PROPERTIES OUTPUT_NAME math-server-benchmarks)
+
+target_link_libraries(benchmarks PRIVATE lexer)
+target_include_directories(benchmarks PRIVATE ../..)
+
+target_link_libraries(benchmarks PRIVATE benchmark benchmark_main)
+
+install(TARGETS benchmarks RUNTIME DESTINATION bin)
+if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
+    install(FILES "$<TARGET_PDB_FILE:benchmarks>" DESTINATION bin OPTIONAL)
+endif()
diff --git a/test/benchmarks/lexer.cpp b/test/benchmarks/lexer.cpp
new file mode 100644
index 0000000..0f3151f
--- /dev/null
+++ b/test/benchmarks/lexer.cpp
@@ -0,0 +1,25 @@
+#include <server/lexer/details/parse.hpp>
+
+#include <benchmark/benchmark.h>
+
+class SelectionOfNumbers : public benchmark::Fixture {
+protected:
+    std::vector<std::string_view> m_numbers{
+        "0",
+        "123",
+        "0.123",
+        ".123",
+        "1e9",
+        "1.87E-18",
+        "012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789.012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789",
+    };
+};
+
+BENCHMARK_F(SelectionOfNumbers, ParseStdRegex)(benchmark::State &state) {
+    using namespace math::server::lexer::details;
+    for (auto _ : state) {
+        for (const auto& src : m_numbers) {
+            parse_number(src);
+        }
+    }
+}